README: Bring back NVIDIA issues note

* Implement version checking in IPC

implement version checking; streamed IPC

streamed IPC will allow multiple requests per connection

add nonsense request

change inline struct to json macro

only check version if request actually fails

fix usage of inspect_err (MSRV 1.72.0; stabilized 1.76.0)

"nonsense request" -> "return error"

oneshot connections

* Change some things around

* Unqualify niri_ipc::Transform

---------

Co-authored-by: Ivan Molodetskikh <yalterz@gmail.com>

.gitattributes

@@ -0,0 +1 @@
+*.png filter=lfs diff=lfs merge=lfs -text

.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,21 @@
+---
+name: Bug report
+about: Report a bug or a crash
+title: ''
+labels: bug
+assignees: ''
+
+---
+
+<!-- Please describe the issue here at the top, then fill in the system information below. -->
+
+### System Information
+
+<!-- Paste the output of `niri -V`, e.g. niri 0.1.0-beta.1 (v0.1.0-beta.1) -->
+* niri version: 
+
+<!-- Write your GPU vendor and model, e.g. AMD RX 6700M -->
+* GPU: 
+
+<!-- Write your CPU vendor and model, e.g. AMD Ryzen 7 6800H -->
+* CPU:

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,4 @@
+contact_links:
+  - name: Feature request
+    url: https://github.com/YaLTeR/niri/discussions/new?category=ideas
+    about: Ideas for new features and functionality (start a Discussion)

.github/workflows/ci.yml

@@ -24,6 +24,7 @@ jobs:
 
     name: test - ${{ matrix.configuration }}
     runs-on: ubuntu-22.04
+    container: ubuntu:23.10
 
     steps:
       - uses: actions/checkout@v4
@@ -32,34 +33,90 @@ jobs:
 
       - name: Install dependencies
         run: |
-          sudo apt-get install -y software-properties-common
+          apt-get update -y
-          sudo add-apt-repository -y ppa:pipewire-debian/pipewire-upstream
+          apt-get install -y curl gcc clang libudev-dev libgbm-dev libxkbcommon-dev libegl1-mesa-dev libwayland-dev libinput-dev libdbus-1-dev libsystemd-dev libseat-dev libpipewire-0.3-dev libpango1.0-dev
-          sudo apt-get update -y
-          sudo apt-get install -y libudev-dev libgbm-dev libxkbcommon-dev libegl1-mesa-dev libwayland-dev libinput-dev libdbus-1-dev libsystemd-dev libseat-dev libpipewire-0.3-dev libpango1.0-dev
 
-      - name: Install Rust
+      - uses: dtolnay/rust-toolchain@stable
-        run: |
-          rustup set auto-self-update check-only
-          rustup toolchain install stable --profile minimal
 
       - uses: Swatinem/rust-cache@v2
         with:
           key: ${{ matrix.configuration }}
 
-      - name: Build (no default features)
+      - name: Check (no default features)
-        run: cargo build ${{ matrix.release-flag }} --no-default-features
+        run: cargo check ${{ matrix.release-flag }} --no-default-features
 
-      - name: Build
+      - name: Check (just dbus)
-        run: cargo build ${{ matrix.release-flag }}
+        run: cargo check ${{ matrix.release-flag }} --no-default-features --features dbus
+
+      - name: Check (just systemd)
+        run: cargo check ${{ matrix.release-flag }} --no-default-features --features systemd
+
+      - name: Check (just dinit)
+        run: cargo check ${{ matrix.release-flag }} --no-default-features --features dinit
+
+      - name: Check (just xdp-gnome-screencast)
+        run: cargo check ${{ matrix.release-flag }} --no-default-features --features xdp-gnome-screencast
+
+      - name: Check
+        run: cargo check ${{ matrix.release-flag }}
 
       - name: Build (with profiling)
         run: cargo build ${{ matrix.release-flag }} --features profile-with-tracy
 
       - name: Build Tests
-        run: cargo test --no-run --all ${{ matrix.release-flag }}
+        run: cargo test --no-run --all --exclude niri-visual-tests ${{ matrix.release-flag }}
 
       - name: Test
-        run: cargo test --all ${{ matrix.release-flag }} -- --nocapture
+        run: cargo test --all --exclude niri-visual-tests ${{ matrix.release-flag }} -- --nocapture
+
+  visual-tests:
+    strategy:
+      fail-fast: false
+
+    name: visual tests
+    runs-on: ubuntu-22.04
+    container: ubuntu:23.10
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          show-progress: false
+
+      - name: Install dependencies
+        run: |
+          apt-get update -y
+          apt-get install -y curl gcc clang libudev-dev libgbm-dev libxkbcommon-dev libegl1-mesa-dev libwayland-dev libinput-dev libdbus-1-dev libsystemd-dev libseat-dev libpipewire-0.3-dev libpango1.0-dev libadwaita-1-dev
+
+      - uses: dtolnay/rust-toolchain@stable
+
+      - uses: Swatinem/rust-cache@v2
+
+      - name: Build
+        run: cargo build --package niri-visual-tests
+
+  msrv:
+    strategy:
+      fail-fast: false
+
+    name: 'msrv - 1.72.0'
+    runs-on: ubuntu-22.04
+    container: ubuntu:23.10
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          show-progress: false
+
+      - name: Install dependencies
+        run: |
+          apt-get update -y
+          apt-get install -y curl gcc clang libudev-dev libgbm-dev libxkbcommon-dev libegl1-mesa-dev libwayland-dev libinput-dev libdbus-1-dev libsystemd-dev libseat-dev libpipewire-0.3-dev libpango1.0-dev libadwaita-1-dev
+
+      - uses: dtolnay/rust-toolchain@1.72.0
+
+      - uses: Swatinem/rust-cache@v2
+
+      - run: cargo check --all-targets
 
   clippy:
     strategy:
@@ -67,6 +124,7 @@ jobs:
 
     name: clippy
     runs-on: ubuntu-22.04
+    container: ubuntu:23.10
 
     steps:
       - uses: actions/checkout@v4
@@ -75,15 +133,12 @@ jobs:
 
       - name: Install dependencies
         run: |
-          sudo apt-get install -y software-properties-common
+          apt-get update -y
-          sudo add-apt-repository -y ppa:pipewire-debian/pipewire-upstream
+          apt-get install -y curl gcc clang libudev-dev libgbm-dev libxkbcommon-dev libegl1-mesa-dev libwayland-dev libinput-dev libdbus-1-dev libsystemd-dev libseat-dev libpipewire-0.3-dev libpango1.0-dev libadwaita-1-dev
-          sudo apt-get update -y
-          sudo apt-get install -y libudev-dev libgbm-dev libxkbcommon-dev libegl1-mesa-dev libwayland-dev libinput-dev libdbus-1-dev libsystemd-dev libseat-dev libpipewire-0.3-dev libpango1.0-dev
 
-      - name: Install Rust
+      - uses: dtolnay/rust-toolchain@stable
-        run: |
+        with:
-          rustup set auto-self-update check-only
+          components: clippy
-          rustup toolchain install stable --profile minimal --component clippy
 
       - uses: Swatinem/rust-cache@v2
 
@@ -119,8 +174,38 @@ jobs:
       - name: Install dependencies
         run: |
           sudo dnf update -y
-          sudo dnf install -y cargo gcc libudev-devel libgbm-devel libxkbcommon-devel wayland-devel libinput-devel dbus-devel systemd-devel libseat-devel pipewire-devel pango-devel cairo-gobject-devel clang
+          sudo dnf install -y cargo gcc libudev-devel libgbm-devel libxkbcommon-devel wayland-devel libinput-devel dbus-devel systemd-devel libseat-devel pipewire-devel pango-devel cairo-gobject-devel clang libadwaita-devel
 
       - uses: Swatinem/rust-cache@v2
-      - run: cargo build
+      - run: cargo build --all
 
+  nix:
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          show-progress: false
+
+      - name: Check flake inputs
+        uses: DeterminateSystems/flake-checker-action@v4
+        continue-on-error: true
+
+      - name: Install Nix
+        uses: DeterminateSystems/nix-installer-action@v3
+        continue-on-error: true
+
+      - run: nix build
+        continue-on-error: true
+
+  publish-wiki:
+    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+    needs: build
+    permissions:
+      contents: write
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          lfs: true
+          show-progress: false
+      - uses: Andrew-Chen-Wang/github-wiki-action@86138cbd6328b21d759e89ab6e6dd6a139b22270

Cargo.toml

@@ -1,5 +1,8 @@
+[workspace]
+members = ["niri-visual-tests"]
+
 [workspace.package]
-version = "0.1.0-beta.1"
+version = "0.1.5"
 description = "A scrollable-tiling Wayland compositor"
 authors = ["Ivan Molodetskikh <yalterz@gmail.com>"]
 license = "GPL-3.0-or-later"
@@ -7,11 +10,14 @@ edition = "2021"
 repository = "https://github.com/YaLTeR/niri"
 
 [workspace.dependencies]
-bitflags = "2.4.2"
+anyhow = "1.0.81"
-directories = "5.0.1"
+bitflags = "2.5.0"
-serde = { version = "1.0.195", features = ["derive"] }
+clap = { version = "~4.4.18", features = ["derive"] }
+serde = { version = "1.0.197", features = ["derive"] }
+serde_json = "1.0.115"
 tracing = { version = "0.1.40", features = ["max_level_trace", "release_max_level_debug"] }
-tracy-client = { version = "0.16.5", default-features = false }
+tracing-subscriber = { version = "0.3.18", features = ["env-filter"] }
+tracy-client = { version = "0.17.0", default-features = false }
 
 [workspace.dependencies.smithay]
 git = "https://github.com/Smithay/smithay.git"
@@ -35,38 +41,41 @@ readme = "README.md"
 keywords = ["wayland", "compositor", "tiling", "smithay", "wm"]
 
 [dependencies]
-anyhow = { version = "1.0.79" }
+anyhow.workspace = true
 arrayvec = "0.7.4"
-async-channel = { version = "2.1.1", optional = true }
+async-channel = { version = "2.2.0", optional = true }
 async-io = { version = "1.13.0", optional = true }
-bitflags = "2.4.2"
+bitflags.workspace = true
-calloop = { version = "0.12.4", features = ["executor", "futures-io"] }
+bytemuck = { version = "1.15.0", features = ["derive"] }
-clap = { version = "4.4.18", features = ["derive", "string"] }
+calloop = { version = "0.13.0", features = ["executor", "futures-io"] }
+clap = { workspace = true, features = ["string"] }
 directories = "5.0.1"
+drm-ffi = "0.7.1"
 futures-util = { version = "0.3.30", default-features = false, features = ["std", "io"] }
 git-version = "0.3.9"
+glam = "0.27.0"
+input = { version = "0.9.0", features = ["libinput_1_21"] }
 keyframe = { version = "1.1.1", default-features = false }
-libc = "0.2.152"
+libc = "0.2.153"
-log = { version = "0.4.20", features = ["max_level_trace", "release_max_level_debug"] }
+log = { version = "0.4.21", features = ["max_level_trace", "release_max_level_debug"] }
-logind-zbus = { version = "3.1.2", optional = true }
+niri-config = { version = "0.1.5", path = "niri-config" }
-niri-config = { version = "0.1.0-beta.1", path = "niri-config" }
+niri-ipc = { version = "0.1.5", path = "niri-ipc", features = ["clap"] }
-niri-ipc = { version = "0.1.0-beta.1", path = "niri-ipc" }
 notify-rust = { version = "4.10.0", optional = true }
-pangocairo = "0.18.0"
+pangocairo = "0.19.2"
-pipewire = { version = "0.7.2", optional = true }
+pipewire = { version = "0.8.0", optional = true }
-png = "0.17.11"
+png = "0.17.13"
 portable-atomic = { version = "1.6.0", default-features = false, features = ["float"] }
-profiling = "1.0.13"
+profiling = "1.0.15"
 sd-notify = "0.4.1"
 serde.workspace = true
-serde_json = "1.0.111"
+serde_json.workspace = true
 smithay-drm-extras.workspace = true
-tracing-subscriber = { version = "0.3.18", features = ["env-filter"] }
+tracing-subscriber.workspace = true
 tracing.workspace = true
 tracy-client.workspace = true
 url = { version = "2.5.0", optional = true }
 xcursor = "0.3.5"
-zbus = { version = "3.14.1", optional = true }
+zbus = { version = "~3.15.2", optional = true }
 
 [dependencies.smithay]
 workspace = true
@@ -80,6 +89,7 @@ features = [
     "backend_winit",
     "desktop",
     "renderer_gl",
+    "renderer_pixman",
     "renderer_multi",
     "use_system_lib",
     "wayland_frontend",
@@ -88,15 +98,20 @@ features = [
 [dev-dependencies]
 proptest = "1.4.0"
 proptest-derive = "0.4.0"
+xshell = "0.2.5"
 
 [features]
-default = ["dbus", "xdp-gnome-screencast"]
+default = ["dbus", "systemd", "xdp-gnome-screencast"]
-# Enables DBus support (required for xdp-gnome and power button inhibiting).
+# Enables D-Bus support (serve various freedesktop and GNOME interfaces, power button handling).
-dbus = ["zbus", "logind-zbus", "async-channel", "async-io", "notify-rust", "url"]
+dbus = ["zbus", "async-channel", "async-io", "notify-rust", "url"]
+# Enables systemd integration (global environment, apps in transient scopes).
+systemd = ["dbus"]
 # Enables screencasting support through xdg-desktop-portal-gnome.
 xdp-gnome-screencast = ["dbus", "pipewire"]
 # Enables the Tracy profiler instrumentation.
 profile-with-tracy = ["profiling/profile-with-tracy", "tracy-client/default"]
+# Enables dinit integration (global environment).
+dinit = []
 
 [profile.release]
 debug = "line-tables-only"
@@ -108,7 +123,7 @@ lto = "thin"
 debug = false
 
 [package.metadata.generate-rpm]
-version = "0.1.0~beta.1"
+version = "0.1.5"
 assets = [
     { source = "target/release/niri", dest = "/usr/bin/", mode = "755" },
     { source = "resources/niri-session", dest = "/usr/bin/", mode = "755" },
@@ -119,3 +134,4 @@ assets = [
 ]
 [package.metadata.generate-rpm.requires]
 alacritty = "*"
+fuzzel = "*"

README.md

@@ -6,7 +6,11 @@
     <a href="https://github.com/YaLTeR/niri/releases"><img alt="GitHub Release" src="https://img.shields.io/github/v/release/YaLTeR/niri?logo=github"></a>
 </p>
 
-![](https://github.com/YaLTeR/niri/assets/1794388/16f87a4a-afac-49aa-b3e6-5e6f16c943a9)
+<p align="center">
+    <a href="https://github.com/YaLTeR/niri/wiki/Getting-Started">Getting Started</a> | <a href="https://github.com/YaLTeR/niri/wiki/Configuration:-Overview">Configuration</a>
+</p>
+
+![](https://github.com/YaLTeR/niri/assets/1794388/2b246c2c-7cf3-4a11-96eb-ad0c7f2f4ed6)
 
 ## About
 
@@ -16,26 +20,35 @@ Opening a new window never causes existing windows to resize.
 Every monitor has its own separate window strip.
 Windows can never "overflow" onto an adjacent monitor.
 
-Since windows go left-to-right horizontally, workspaces are arranged vertically.
+Workspaces are dynamic and arranged vertically.
 Every monitor has an independent set of workspaces, and there's always one empty workspace present all the way down.
 
+The workspace arrangement is preserved across disconnecting and connecting monitors where it makes sense.
+When a monitor disconnects, its workspaces will move to another monitor, but upon reconnection they will move back to the original monitor.
+
 ## Features
 
 - Scrollable tiling
 - Dynamic workspaces like in GNOME
 - Built-in screenshot UI
 - Monitor screencasting through xdg-desktop-portal-gnome
-- Touchpad gesture to switch workspaces
+    - You can [block out](https://github.com/YaLTeR/niri/wiki/Configuration:-Window-Rules#block-out-from) sensitive windows from screencasts
+- [Touchpad gestures](https://github.com/YaLTeR/niri/assets/1794388/946a910e-9bec-4cd1-a923-4a9421707515)
 - Configurable layout: gaps, borders, struts, window sizes
+- [Animations](https://github.com/YaLTeR/niri/assets/1794388/ce178da2-af9e-4c51-876f-8709c241d95e)
 - Live-reloading config
 
+## Video Demo
+
+https://github.com/YaLTeR/niri/assets/1794388/bce834b0-f205-434e-a027-b373495f9729
+
 ## Status
 
 A lot of the essential functionality is implemented, plus some goodies on top.
-Feel free to give niri a try.
+Feel free to give niri a try: follow the instructions on the [Getting Started](https://github.com/YaLTeR/niri/wiki/Getting-Started) wiki page.
-Have your waybars and fuzzels ready: niri is not a complete desktop environment.
+Have your [waybar]s and [fuzzel]s ready: niri is not a complete desktop environment.
 
-https://github.com/YaLTeR/niri/assets/1794388/5d355694-7b06-4f00-8920-8dce54a8721c
+Note that NVIDIA GPUs may have issues.
 
 ## Inspiration
 
@@ -44,162 +57,11 @@ Niri is heavily inspired by [PaperWM] which implements scrollable tiling on top
 One of the reasons that prompted me to try writing my own compositor is being able to properly separate the monitors.
 Being a GNOME Shell extension, PaperWM has to work against Shell's global window coordinate space to prevent windows from overflowing.
 
-Niri tries to preserve the workspace arrangement as much as possible upon disconnecting and connecting monitors.
-When a monitor disconnects, its workspaces will move to another monitor, but upon reconnection they will move back to the original monitor.
-
-## Building
-
-> [!TIP]
-> For Fedora users, there's a COPR with built and packaged niri: https://copr.fedorainfracloud.org/coprs/yalter/niri/
->
-> For NixOS users, check out https://github.com/sodiboo/niri-flake
-
-First, install the dependencies for your distribution.
-
-- Ubuntu:
-
-    ```sh
-    sudo apt-get install -y software-properties-common
-    sudo add-apt-repository -y ppa:pipewire-debian/pipewire-upstream
-    sudo apt-get update -y
-    sudo apt-get install -y libudev-dev libgbm-dev libxkbcommon-dev libegl1-mesa-dev libwayland-dev libinput-dev libdbus-1-dev libsystemd-dev libseat-dev libpipewire-0.3-dev libpango1.0-dev
-    ```
-
-- Fedora:
-
-    ```sh
-    sudo dnf install gcc libudev-devel libgbm-devel libxkbcommon-devel wayland-devel libinput-devel dbus-devel systemd-devel libseat-devel pipewire-devel pango-devel cairo-gobject-devel clang
-    ```
-
-Next, build niri with `cargo build --release`.
-
-### NixOS/Nix
-
-We have a community-maintained flake which provides a devshell with required dependencies. Use `nix build` to build niri, and then run `./results/bin/niri`.
-    
-If you're not on NixOS, you may need [NixGL](https://github.com/nix-community/nixGL) to run the resulting binary:
-
-```
-nix run --impure github:guibou/nixGL -- ./results/bin/niri
-```
-
-## Installation
-
-The recommended way to install and run niri is as a standalone desktop session.
-To do that, put files into the correct directories according to this table.
-
-| File | Destination |
-| ---- | ----------- |
-| `target/release/niri` | `/usr/bin/` |
-| `resources/niri-session` | `/usr/bin/` |
-| `resources/niri.desktop` | `/usr/share/wayland-sessions/` |
-| `resources/niri-portals.conf` | `/usr/share/xdg-desktop-portal/` |
-| `resources/niri.service` | `/usr/lib/systemd/user/` |
-| `resources/niri-shutdown.target` | `/usr/lib/systemd/user/` |
-
-Doing this will make niri appear in GDM and, presumably, other display managers.
-
-## Running
-
-`cargo run --release`
-
-Inside an existing desktop session, it will run in a window.
-On a TTY, it will run natively.
-
-To exit when running on a TTY, press <kbd>Super</kbd><kbd>Shift</kbd><kbd>E</kbd>.
-
-### Session
-
-If you followed the recommended installation steps above, niri should appear in your display manager.
-Starting it from there will run niri as a desktop session.
-
-The niri session will autostart apps through the systemd xdg-autostart target.
-You can also autostart systemd services like [mako] by symlinking them into `$HOME/.config/systemd/user/niri.service.wants/`.
-A step-by-step process for this is explained [on the wiki](https://github.com/YaLTeR/niri/wiki/Example-systemd-Setup).
-
-Niri also works with some parts of xdg-desktop-portal-gnome.
-In particular, it supports file choosers and monitor screencasting (e.g. to [OBS]).
-
-[This wiki page](https://github.com/YaLTeR/niri/wiki/Important-Software) explains how to run important software required for normal desktop use, including portals.
-
-### Xwayland
-
-See [the wiki page](https://github.com/YaLTeR/niri/wiki/Xwayland) to learn how to use Xwayland with niri.
-
-### IPC
-
-You can communicate with the running niri instance over an IPC socket.
-Check `niri msg --help` for available commands.
-
-The `--json` flag prints the response in JSON, rather than formatted.
-For example, `niri msg --json outputs`.
-
-For programmatic access, check the [niri-ipc sub-crate](./niri-ipc/) which defines the types.
-The communication over the IPC socket happens in JSON.
-
-## Default Hotkeys
-
-When running on a TTY, the Mod key is <kbd>Super</kbd>.
-When running in a window, the Mod key is <kbd>Alt</kbd>.
-
-The general system is: if a hotkey switches somewhere, then adding <kbd>Ctrl</kbd> will move the focused window or column there.
-
-| Hotkey | Description |
-| ------ | ----------- |
-| <kbd>Mod</kbd><kbd>Shift</kbd><kbd>/</kbd> | Show a list of important niri hotkeys |
-| <kbd>Mod</kbd><kbd>T</kbd> | Spawn `alacritty` (terminal) |
-| <kbd>Mod</kbd><kbd>D</kbd> | Spawn `fuzzel` (application launcher) |
-| <kbd>Mod</kbd><kbd>Alt</kbd><kbd>L</kbd> | Spawn `swaylock` (screen locker) |
-| <kbd>Mod</kbd><kbd>Q</kbd> | Close the focused window |
-| <kbd>Mod</kbd><kbd>H</kbd> or <kbd>Mod</kbd><kbd>←</kbd> | Focus the column to the left |
-| <kbd>Mod</kbd><kbd>L</kbd> or <kbd>Mod</kbd><kbd>→</kbd> | Focus the column to the right |
-| <kbd>Mod</kbd><kbd>J</kbd> or <kbd>Mod</kbd><kbd>↓</kbd> | Focus the window below in a column |
-| <kbd>Mod</kbd><kbd>K</kbd> or <kbd>Mod</kbd><kbd>↑</kbd> | Focus the window above in a column |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>H</kbd> or <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>←</kbd> | Move the focused column to the left |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>L</kbd> or <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>→</kbd> | Move the focused column to the right |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>J</kbd> or <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>↓</kbd> | Move the focused window below in a column |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>K</kbd> or <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>↑</kbd> | Move the focused window above in a column |
-| <kbd>Mod</kbd><kbd>Home</kbd> and <kbd>Mod</kbd><kbd>End</kbd> | Focus the first or the last column |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>Home</kbd> and <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>End</kbd> | Move the focused column to the very start or to the very end |
-| <kbd>Mod</kbd><kbd>Shift</kbd><kbd>H</kbd><kbd>J</kbd><kbd>K</kbd><kbd>L</kbd> or <kbd>Mod</kbd><kbd>Shift</kbd><kbd>←</kbd><kbd>↓</kbd><kbd>↑</kbd><kbd>→</kbd> | Focus the monitor to the side |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>Shift</kbd><kbd>H</kbd><kbd>J</kbd><kbd>K</kbd><kbd>L</kbd> or <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>Shift</kbd><kbd>←</kbd><kbd>↓</kbd><kbd>↑</kbd><kbd>→</kbd> | Move the focused column to the monitor to the side |
-| <kbd>Mod</kbd><kbd>U</kbd> or <kbd>Mod</kbd><kbd>PageDown</kbd> | Switch to the workspace below |
-| <kbd>Mod</kbd><kbd>I</kbd> or <kbd>Mod</kbd><kbd>PageUp</kbd> | Switch to the workspace above |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>U</kbd> or <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>PageDown</kbd> | Move the focused column to the workspace below |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>I</kbd> or <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>PageUp</kbd> | Move the focused column to the workspace above |
-| <kbd>Mod</kbd><kbd>1</kbd>–<kbd>9</kbd> | Switch to a workspace by index |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>1</kbd>–<kbd>9</kbd> | Move the focused column to a workspace by index |
-| <kbd>Mod</kbd><kbd>Shift</kbd><kbd>U</kbd> or <kbd>Mod</kbd><kbd>Shift</kbd><kbd>PageDown</kbd> | Move the focused workspace down |
-| <kbd>Mod</kbd><kbd>Shift</kbd><kbd>I</kbd> or <kbd>Mod</kbd><kbd>Shift</kbd><kbd>PageUp</kbd> | Move the focused workspace up |
-| <kbd>Mod</kbd><kbd>,</kbd> | Consume the window to the right into the focused column |
-| <kbd>Mod</kbd><kbd>.</kbd> | Expel the focused window into its own column |
-| <kbd>Mod</kbd><kbd>R</kbd> | Toggle between preset column widths |
-| <kbd>Mod</kbd><kbd>F</kbd> | Maximize column |
-| <kbd>Mod</kbd><kbd>C</kbd> | Center column within view |
-| <kbd>Mod</kbd><kbd>-</kbd> | Decrease column width by 10% |
-| <kbd>Mod</kbd><kbd>=</kbd> | Increase column width by 10% |
-| <kbd>Mod</kbd><kbd>Shift</kbd><kbd>-</kbd> | Decrease window height by 10% |
-| <kbd>Mod</kbd><kbd>Shift</kbd><kbd>=</kbd> | Increase window height by 10% |
-| <kbd>Mod</kbd><kbd>Shift</kbd><kbd>F</kbd> | Toggle full-screen on the focused window |
-| <kbd>PrtSc</kbd> | Take an area screenshot. Select the area to screenshot with mouse, then press Space to save the screenshot, or Escape to cancel |
-| <kbd>Alt</kbd><kbd>PrtSc</kbd> | Take a screenshot of the focused window to clipboard and to `~/Pictures/Screenshots/` |
-| <kbd>Ctrl</kbd><kbd>PrtSc</kbd> | Take a screenshot of the focused monitor to clipboard and to `~/Pictures/Screenshots/` |
-| <kbd>Mod</kbd><kbd>Ctrl</kbd><kbd>Shift</kbd><kbd>T</kbd> | Toggle debug tinting of rendered elements |
-| <kbd>Mod</kbd><kbd>Shift</kbd><kbd>E</kbd> | Exit niri |
-
-## Configuration
-
-Niri will load configuration from `$XDG_CONFIG_HOME/.config/niri/config.kdl` or `~/.config/niri/config.kdl`.
-If this fails, it will load [the default configuration file](resources/default-config.kdl).
-Please use the default configuration file as the starting point for your custom configuration.
-
-Niri will live-reload most of the configuration settings, like key binds or gaps or output modes, as you change the config file.
-
 ## Contact
 
 We have a Matrix chat, feel free to join and ask a question: https://matrix.to/#/#niri:matrix.org
 
 [PaperWM]: https://github.com/paperwm/PaperWM
-[mako]: https://github.com/emersion/mako
+[waybar]: https://github.com/Alexays/Waybar
-[OBS]: https://flathub.org/apps/com.obsproject.Studio
+[fuzzel]: https://codeberg.org/dnkl/fuzzel
 

flake.lock

@@ -7,11 +7,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1702918879,
+        "lastModified": 1709610799,
-        "narHash": "sha256-tWJqzajIvYcaRWxn+cLUB9L9Pv4dQ3Bfit/YjU5ze3g=",
+        "narHash": "sha256-5jfLQx0U9hXbi2skYMGodDJkIgffrjIOgMRjZqms2QE=",
         "owner": "ipetkov",
         "repo": "crane",
-        "rev": "7195c00c272fdd92fc74e7d5a0a2844b9fadb2fb",
+        "rev": "81c393c776d5379c030607866afef6406ca1be57",
         "type": "github"
       },
       "original": {
@@ -28,11 +28,11 @@
         "rust-analyzer-src": "rust-analyzer-src"
       },
       "locked": {
-        "lastModified": 1701411808,
+        "lastModified": 1709274179,
-        "narHash": "sha256-K8QDx8UgbvGdENuvPvcsCXcd8brd55OkRDFLBT7xUVY=",
+        "narHash": "sha256-O6EC6QELBLHzhdzBOJj0chx8AOcd4nDRECIagfT5Nd0=",
         "owner": "nix-community",
         "repo": "fenix",
-        "rev": "3776d0e2a30184cc6a0ba20fb86dc6df5b41fccd",
+        "rev": "4be608f4f81d351aacca01b21ffd91028c23cc22",
         "type": "github"
       },
       "original": {
@@ -47,11 +47,11 @@
         "systems": "systems"
       },
       "locked": {
-        "lastModified": 1701680307,
+        "lastModified": 1709126324,
-        "narHash": "sha256-kAuep2h5ajznlPMD9rnQyffWG8EM/C73lejGofXvdM8=",
+        "narHash": "sha256-q6EQdSeUZOG26WelxqkmR7kArjgWCdw5sfJVHPH/7j8=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "4022d587cbbfd70fe950c1e2083a02621806a725",
+        "rev": "d465f4819400de7c8d874d50b982301f28a84605",
         "type": "github"
       },
       "original": {
@@ -62,11 +62,11 @@
     },
     "nix-filter": {
       "locked": {
-        "lastModified": 1701697642,
+        "lastModified": 1705332318,
-        "narHash": "sha256-L217WytWZHSY8GW9Gx1A64OnNctbuDbfslaTEofXXRw=",
+        "narHash": "sha256-kcw1yFeJe9N4PjQji9ZeX47jg0p9A0DuU4djKvg1a7I=",
         "owner": "numtide",
         "repo": "nix-filter",
-        "rev": "c843418ecfd0344ecb85844b082ff5675e02c443",
+        "rev": "3449dc925982ad46246cfc36469baf66e1b64f17",
         "type": "github"
       },
       "original": {
@@ -77,11 +77,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1702900294,
+        "lastModified": 1709386671,
-        "narHash": "sha256-pt7sSoJYNw3n8YtXw0Z/Nnr6/PfY2YrjDvqboErXnRM=",
+        "narHash": "sha256-VPqfBnIJ+cfa78pd4Y5Cr6sOWVW8GYHRVucxJGmRf8Q=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "886c9aee6ca9324e127f9c2c4e6f68c2641c8256",
+        "rev": "fa9a51752f1b5de583ad5213eb621be071806663",
         "type": "github"
       },
       "original": {
@@ -103,11 +103,11 @@
     "rust-analyzer-src": {
       "flake": false,
       "locked": {
-        "lastModified": 1701372675,
+        "lastModified": 1709219524,
-        "narHash": "sha256-MSHhnAoLjJuoPxzsTzBOzNhjhlCTHPs4nvkPAZVV1eY=",
+        "narHash": "sha256-8HHRXm4kYQLdUohNDUuCC3Rge7fXrtkjBUf0GERxrkM=",
         "owner": "rust-lang",
         "repo": "rust-analyzer",
-        "rev": "c9d189d1375e59a6c9b4d62fdede94ade001f6ee",
+        "rev": "9efa23c4dacee88b93540632eb3d88c5dfebfe17",
         "type": "github"
       },
       "original": {

flake.nix

@@ -39,22 +39,22 @@
           pname = "niri";
           version = self.rev or "dirty";
 
-          src = nix-filter.lib.filter {
+          src = nixpkgs.lib.cleanSourceWith {
-            root = ./.;
+            src = craneLib.path ./.;
-            include = [
+            filter = path: type:
-              ./src
+              (builtins.match "resources" path == null) ||
-              ./niri-config
+              ((craneLib.filterCargoSources path type) &&
-              ./niri-ipc
+              (builtins.match "niri-visual-tests" path == null));
-              ./Cargo.toml
-              ./Cargo.lock
-              ./resources
-            ];
           };
 
           nativeBuildInputs = with pkgs; [
             pkg-config
             autoPatchelfHook
             clang
+            gdk-pixbuf
+            graphene
+            gtk4
+            libadwaita
           ];
 
           buildInputs = with pkgs; [

niri-config/Cargo.toml

@@ -9,8 +9,11 @@ repository.workspace = true
 
 [dependencies]
 bitflags.workspace = true
+csscolorparser = "0.6.2"
 knuffel = "3.2.0"
 miette = "5.10.0"
-smithay.workspace = true
+niri-ipc = { version = "0.1.5", path = "../niri-ipc" }
+regex = "1.10.4"
+smithay = { workspace = true, features = ["backend_libinput"] }
 tracing.workspace = true
 tracy-client.workspace = true

niri-ipc/Cargo.toml

@@ -8,4 +8,9 @@ edition.workspace = true
 repository.workspace = true
 
 [dependencies]
+clap = { workspace = true, optional = true }
 serde.workspace = true
+serde_json.workspace = true
+
+[features]
+clap = ["dep:clap"]

niri-ipc/src/lib.rs

@@ -2,26 +2,243 @@
 #![warn(missing_docs)]
 
 use std::collections::HashMap;
+use std::str::FromStr;
 
 use serde::{Deserialize, Serialize};
 
-/// Name of the environment variable containing the niri IPC socket path.
+mod socket;
-pub const SOCKET_PATH_ENV: &str = "NIRI_SOCKET";
+pub use socket::{Socket, SOCKET_PATH_ENV};
 
 /// Request from client to niri.
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Serialize, Deserialize, Clone)]
 pub enum Request {
+    /// Request the version string for the running niri instance.
+    Version,
     /// Request information about connected outputs.
     Outputs,
+    /// Request information about the focused window.
+    FocusedWindow,
+    /// Perform an action.
+    Action(Action),
+    /// Respond with an error (for testing error handling).
+    ReturnError,
 }
 
-/// Response from niri to client.
+/// Reply from niri to client.
-#[derive(Debug, Serialize, Deserialize)]
+///
+/// Every request gets one reply.
+///
+/// * If an error had occurred, it will be an `Reply::Err`.
+/// * If the request does not need any particular response, it will be
+///   `Reply::Ok(Response::Handled)`. Kind of like an `Ok(())`.
+/// * Otherwise, it will be `Reply::Ok(response)` with one of the other [`Response`] variants.
+pub type Reply = Result<Response, String>;
+
+/// Successful response from niri to client.
+#[derive(Debug, Serialize, Deserialize, Clone)]
 pub enum Response {
+    /// A request that does not need a response was handled successfully.
+    Handled,
+    /// The version string for the running niri instance.
+    Version(String),
     /// Information about connected outputs.
     ///
     /// Map from connector name to output info.
     Outputs(HashMap<String, Output>),
+    /// Information about the focused window.
+    FocusedWindow(Option<Window>),
+}
+
+/// Actions that niri can perform.
+// Variants in this enum should match the spelling of the ones in niri-config. Most, but not all,
+// variants from niri-config should be present here.
+#[derive(Serialize, Deserialize, Debug, Clone)]
+#[cfg_attr(feature = "clap", derive(clap::Parser))]
+#[cfg_attr(feature = "clap", command(subcommand_value_name = "ACTION"))]
+#[cfg_attr(feature = "clap", command(subcommand_help_heading = "Actions"))]
+pub enum Action {
+    /// Exit niri.
+    Quit {
+        /// Skip the "Press Enter to confirm" prompt.
+        #[cfg_attr(feature = "clap", arg(short, long))]
+        skip_confirmation: bool,
+    },
+    /// Power off all monitors via DPMS.
+    PowerOffMonitors,
+    /// Spawn a command.
+    Spawn {
+        /// Command to spawn.
+        #[cfg_attr(feature = "clap", arg(last = true, required = true))]
+        command: Vec<String>,
+    },
+    /// Open the screenshot UI.
+    Screenshot,
+    /// Screenshot the focused screen.
+    ScreenshotScreen,
+    /// Screenshot the focused window.
+    ScreenshotWindow,
+    /// Close the focused window.
+    CloseWindow,
+    /// Toggle fullscreen on the focused window.
+    FullscreenWindow,
+    /// Focus the column to the left.
+    FocusColumnLeft,
+    /// Focus the column to the right.
+    FocusColumnRight,
+    /// Focus the first column.
+    FocusColumnFirst,
+    /// Focus the last column.
+    FocusColumnLast,
+    /// Focus the window below.
+    FocusWindowDown,
+    /// Focus the window above.
+    FocusWindowUp,
+    /// Focus the window or the workspace above.
+    FocusWindowOrWorkspaceDown,
+    /// Focus the window or the workspace above.
+    FocusWindowOrWorkspaceUp,
+    /// Move the focused column to the left.
+    MoveColumnLeft,
+    /// Move the focused column to the right.
+    MoveColumnRight,
+    /// Move the focused column to the start of the workspace.
+    MoveColumnToFirst,
+    /// Move the focused column to the end of the workspace.
+    MoveColumnToLast,
+    /// Move the focused window down in a column.
+    MoveWindowDown,
+    /// Move the focused window up in a column.
+    MoveWindowUp,
+    /// Move the focused window down in a column or to the workspace below.
+    MoveWindowDownOrToWorkspaceDown,
+    /// Move the focused window up in a column or to the workspace above.
+    MoveWindowUpOrToWorkspaceUp,
+    /// Consume or expel the focused window left.
+    ConsumeOrExpelWindowLeft,
+    /// Consume or expel the focused window right.
+    ConsumeOrExpelWindowRight,
+    /// Consume the window to the right into the focused column.
+    ConsumeWindowIntoColumn,
+    /// Expel the focused window from the column.
+    ExpelWindowFromColumn,
+    /// Center the focused column on the screen.
+    CenterColumn,
+    /// Focus the workspace below.
+    FocusWorkspaceDown,
+    /// Focus the workspace above.
+    FocusWorkspaceUp,
+    /// Focus a workspace by index.
+    FocusWorkspace {
+        /// Index of the workspace to focus.
+        #[cfg_attr(feature = "clap", arg())]
+        index: u8,
+    },
+    /// Focus the previous workspace.
+    FocusWorkspacePrevious,
+    /// Move the focused window to the workspace below.
+    MoveWindowToWorkspaceDown,
+    /// Move the focused window to the workspace above.
+    MoveWindowToWorkspaceUp,
+    /// Move the focused window to a workspace by index.
+    MoveWindowToWorkspace {
+        /// Index of the target workspace.
+        #[cfg_attr(feature = "clap", arg())]
+        index: u8,
+    },
+    /// Move the focused column to the workspace below.
+    MoveColumnToWorkspaceDown,
+    /// Move the focused column to the workspace above.
+    MoveColumnToWorkspaceUp,
+    /// Move the focused column to a workspace by index.
+    MoveColumnToWorkspace {
+        /// Index of the target workspace.
+        #[cfg_attr(feature = "clap", arg())]
+        index: u8,
+    },
+    /// Move the focused workspace down.
+    MoveWorkspaceDown,
+    /// Move the focused workspace up.
+    MoveWorkspaceUp,
+    /// Focus the monitor to the left.
+    FocusMonitorLeft,
+    /// Focus the monitor to the right.
+    FocusMonitorRight,
+    /// Focus the monitor below.
+    FocusMonitorDown,
+    /// Focus the monitor above.
+    FocusMonitorUp,
+    /// Move the focused window to the monitor to the left.
+    MoveWindowToMonitorLeft,
+    /// Move the focused window to the monitor to the right.
+    MoveWindowToMonitorRight,
+    /// Move the focused window to the monitor below.
+    MoveWindowToMonitorDown,
+    /// Move the focused window to the monitor above.
+    MoveWindowToMonitorUp,
+    /// Move the focused column to the monitor to the left.
+    MoveColumnToMonitorLeft,
+    /// Move the focused column to the monitor to the right.
+    MoveColumnToMonitorRight,
+    /// Move the focused column to the monitor below.
+    MoveColumnToMonitorDown,
+    /// Move the focused column to the monitor above.
+    MoveColumnToMonitorUp,
+    /// Change the height of the focused window.
+    SetWindowHeight {
+        /// How to change the height.
+        #[cfg_attr(feature = "clap", arg())]
+        change: SizeChange,
+    },
+    /// Switch between preset column widths.
+    SwitchPresetColumnWidth,
+    /// Toggle the maximized state of the focused column.
+    MaximizeColumn,
+    /// Change the width of the focused column.
+    SetColumnWidth {
+        /// How to change the width.
+        #[cfg_attr(feature = "clap", arg())]
+        change: SizeChange,
+    },
+    /// Switch between keyboard layouts.
+    SwitchLayout {
+        /// Layout to switch to.
+        #[cfg_attr(feature = "clap", arg())]
+        layout: LayoutSwitchTarget,
+    },
+    /// Show the hotkey overlay.
+    ShowHotkeyOverlay,
+    /// Move the focused workspace to the monitor to the left.
+    MoveWorkspaceToMonitorLeft,
+    /// Move the focused workspace to the monitor to the right.
+    MoveWorkspaceToMonitorRight,
+    /// Move the focused workspace to the monitor below.
+    MoveWorkspaceToMonitorDown,
+    /// Move the focused workspace to the monitor above.
+    MoveWorkspaceToMonitorUp,
+    /// Toggle a debug tint on windows.
+    ToggleDebugTint,
+}
+
+/// Change in window or column size.
+#[derive(Serialize, Deserialize, Debug, Clone, Copy, PartialEq)]
+pub enum SizeChange {
+    /// Set the size in logical pixels.
+    SetFixed(i32),
+    /// Set the size as a proportion of the working area.
+    SetProportion(f64),
+    /// Add or subtract to the current size in logical pixels.
+    AdjustFixed(i32),
+    /// Add or subtract to the current size as a proportion of the working area.
+    AdjustProportion(f64),
+}
+
+/// Layout to switch to.
+#[derive(Serialize, Deserialize, Debug, Clone, Copy, PartialEq, Eq)]
+pub enum LayoutSwitchTarget {
+    /// The next configured layout.
+    Next,
+    /// The previous configured layout.
+    Prev,
 }
 
 /// Connected output.
@@ -41,6 +258,14 @@ pub struct Output {
     ///
     /// `None` if the output is disabled.
     pub current_mode: Option<usize>,
+    /// Whether the output supports variable refresh rate.
+    pub vrr_supported: bool,
+    /// Whether variable refresh rate is enabled on the output.
+    pub vrr_enabled: bool,
+    /// Logical output information.
+    ///
+    /// `None` if the output is not mapped to any logical output (for example, if it is disabled).
+    pub logical: Option<LogicalOutput>,
 }
 
 /// Output mode.
@@ -52,4 +277,129 @@ pub struct Mode {
     pub height: u16,
     /// Refresh rate in millihertz.
     pub refresh_rate: u32,
+    /// Whether this mode is preferred by the monitor.
+    pub is_preferred: bool,
+}
+
+/// Logical output in the compositor's coordinate space.
+#[derive(Debug, Serialize, Deserialize, Clone, Copy)]
+pub struct LogicalOutput {
+    /// Logical X position.
+    pub x: i32,
+    /// Logical Y position.
+    pub y: i32,
+    /// Width in logical pixels.
+    pub width: u32,
+    /// Height in logical pixels.
+    pub height: u32,
+    /// Scale factor.
+    pub scale: f64,
+    /// Transform.
+    pub transform: Transform,
+}
+
+/// Output transform, which goes counter-clockwise.
+#[derive(Serialize, Deserialize, Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Transform {
+    /// Untransformed.
+    Normal,
+    /// Rotated by 90°.
+    #[serde(rename = "90")]
+    _90,
+    /// Rotated by 180°.
+    #[serde(rename = "180")]
+    _180,
+    /// Rotated by 270°.
+    #[serde(rename = "270")]
+    _270,
+    /// Flipped horizontally.
+    Flipped,
+    /// Rotated by 90° and flipped horizontally.
+    Flipped90,
+    /// Flipped vertically.
+    Flipped180,
+    /// Rotated by 270° and flipped horizontally.
+    Flipped270,
+}
+
+/// Toplevel window.
+#[derive(Serialize, Deserialize, Debug, Clone)]
+pub struct Window {
+    /// Title, if set.
+    pub title: Option<String>,
+    /// Application ID, if set.
+    pub app_id: Option<String>,
+}
+
+impl FromStr for SizeChange {
+    type Err = &'static str;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s.split_once('%') {
+            Some((value, empty)) => {
+                if !empty.is_empty() {
+                    return Err("trailing characters after '%' are not allowed");
+                }
+
+                match value.bytes().next() {
+                    Some(b'-' | b'+') => {
+                        let value = value.parse().map_err(|_| "error parsing value")?;
+                        Ok(Self::AdjustProportion(value))
+                    }
+                    Some(_) => {
+                        let value = value.parse().map_err(|_| "error parsing value")?;
+                        Ok(Self::SetProportion(value))
+                    }
+                    None => Err("value is missing"),
+                }
+            }
+            None => {
+                let value = s;
+                match value.bytes().next() {
+                    Some(b'-' | b'+') => {
+                        let value = value.parse().map_err(|_| "error parsing value")?;
+                        Ok(Self::AdjustFixed(value))
+                    }
+                    Some(_) => {
+                        let value = value.parse().map_err(|_| "error parsing value")?;
+                        Ok(Self::SetFixed(value))
+                    }
+                    None => Err("value is missing"),
+                }
+            }
+        }
+    }
+}
+
+impl FromStr for LayoutSwitchTarget {
+    type Err = &'static str;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "next" => Ok(Self::Next),
+            "prev" => Ok(Self::Prev),
+            _ => Err(r#"invalid layout action, can be "next" or "prev""#),
+        }
+    }
+}
+
+impl FromStr for Transform {
+    type Err = &'static str;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        match s {
+            "normal" => Ok(Self::Normal),
+            "90" => Ok(Self::_90),
+            "180" => Ok(Self::_180),
+            "270" => Ok(Self::_270),
+            "flipped" => Ok(Self::Flipped),
+            "flipped-90" => Ok(Self::Flipped90),
+            "flipped-180" => Ok(Self::Flipped180),
+            "flipped-270" => Ok(Self::Flipped270),
+            _ => Err(concat!(
+                r#"invalid transform, can be "90", "180", "270", "#,
+                r#""flipped", "flipped-90", "flipped-180" or "flipped-270""#
+            )),
+        }
+    }
 }

niri-ipc/src/socket.rs

@@ -0,0 +1,63 @@
+//! Helper for blocking communication over the niri socket.
+
+use std::env;
+use std::io::{self, Read, Write};
+use std::net::Shutdown;
+use std::os::unix::net::UnixStream;
+use std::path::Path;
+
+use crate::{Reply, Request};
+
+/// Name of the environment variable containing the niri IPC socket path.
+pub const SOCKET_PATH_ENV: &str = "NIRI_SOCKET";
+
+/// Helper for blocking communication over the niri socket.
+///
+/// This struct is used to communicate with the niri IPC server. It handles the socket connection
+/// and serialization/deserialization of messages.
+pub struct Socket {
+    stream: UnixStream,
+}
+
+impl Socket {
+    /// Connects to the default niri IPC socket.
+    ///
+    /// This is equivalent to calling [`Self::connect_to`] with the path taken from the
+    /// [`SOCKET_PATH_ENV`] environment variable.
+    pub fn connect() -> io::Result<Self> {
+        let socket_path = env::var_os(SOCKET_PATH_ENV).ok_or_else(|| {
+            io::Error::new(
+                io::ErrorKind::NotFound,
+                format!("{SOCKET_PATH_ENV} is not set, are you running this within niri?"),
+            )
+        })?;
+        Self::connect_to(socket_path)
+    }
+
+    /// Connects to the niri IPC socket at the given path.
+    pub fn connect_to(path: impl AsRef<Path>) -> io::Result<Self> {
+        let stream = UnixStream::connect(path.as_ref())?;
+        Ok(Self { stream })
+    }
+
+    /// Sends a request to niri and returns the response.
+    ///
+    /// Return values:
+    ///
+    /// * `Ok(Ok(response))`: successful [`Response`](crate::Response) from niri
+    /// * `Ok(Err(message))`: error message from niri
+    /// * `Err(error)`: error communicating with niri
+    pub fn send(self, request: Request) -> io::Result<Reply> {
+        let Self { mut stream } = self;
+
+        let mut buf = serde_json::to_vec(&request).unwrap();
+        stream.write_all(&buf)?;
+        stream.shutdown(Shutdown::Write)?;
+
+        buf.clear();
+        stream.read_to_end(&mut buf)?;
+
+        let reply = serde_json::from_slice(&buf)?;
+        Ok(reply)
+    }
+}

niri-visual-tests/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "niri-visual-tests"
+version.workspace = true
+description.workspace = true
+authors.workspace = true
+license.workspace = true
+edition.workspace = true
+repository.workspace = true
+
+[dependencies]
+adw = { version = "0.6.0", package = "libadwaita", features = ["v1_4"] }
+anyhow.workspace = true
+gtk = { version = "0.8.1", package = "gtk4", features = ["v4_12"] }
+niri = { version = "0.1.5", path = ".." }
+niri-config = { version = "0.1.5", path = "../niri-config" }
+smithay.workspace = true
+tracing.workspace = true
+tracing-subscriber.workspace = true

niri-visual-tests/README.md

@@ -0,0 +1,14 @@
+# niri-visual-tests
+
+> [!NOTE]
+>
+> This is a development-only app, you shouldn't package it.
+
+This app contains a number of hard-coded test scenarios for visual inspection.
+It uses the real niri layout and rendering code, but with mock windows instead of Wayland clients.
+The idea is to go through the test scenarios and check that everything *looks* right.
+
+## Running
+
+You will need recent GTK and libadwaita.
+Then, `cargo run`.

niri-visual-tests/resources/style.css

@@ -0,0 +1,3 @@
+.anim-control-bar {
+    padding: 12px;
+}

niri-visual-tests/src/cases/gradient_angle.rs

@@ -0,0 +1,76 @@
+use std::f32::consts::{FRAC_PI_2, PI};
+use std::sync::atomic::Ordering;
+use std::time::Duration;
+
+use niri::animation::ANIMATION_SLOWDOWN;
+use niri::render_helpers::gradient::GradientRenderElement;
+use smithay::backend::renderer::element::RenderElement;
+use smithay::backend::renderer::gles::GlesRenderer;
+use smithay::utils::{Logical, Physical, Rectangle, Scale, Size};
+
+use super::TestCase;
+
+pub struct GradientAngle {
+    angle: f32,
+    prev_time: Duration,
+}
+
+impl GradientAngle {
+    pub fn new(_size: Size<i32, Logical>) -> Self {
+        Self {
+            angle: 0.,
+            prev_time: Duration::ZERO,
+        }
+    }
+}
+
+impl TestCase for GradientAngle {
+    fn are_animations_ongoing(&self) -> bool {
+        true
+    }
+
+    fn advance_animations(&mut self, current_time: Duration) {
+        let mut delta = if self.prev_time.is_zero() {
+            Duration::ZERO
+        } else {
+            current_time.saturating_sub(self.prev_time)
+        };
+        self.prev_time = current_time;
+
+        let slowdown = ANIMATION_SLOWDOWN.load(Ordering::SeqCst);
+        if slowdown == 0. {
+            delta = Duration::ZERO
+        } else {
+            delta = delta.div_f64(slowdown);
+        }
+
+        self.angle += delta.as_secs_f32() * PI;
+
+        if self.angle >= PI * 2. {
+            self.angle -= PI * 2.
+        }
+    }
+
+    fn render(
+        &mut self,
+        renderer: &mut GlesRenderer,
+        size: Size<i32, Physical>,
+    ) -> Vec<Box<dyn RenderElement<GlesRenderer>>> {
+        let (a, b) = (size.w / 4, size.h / 4);
+        let size = (size.w - a * 2, size.h - b * 2);
+        let area = Rectangle::from_loc_and_size((a, b), size);
+
+        GradientRenderElement::new(
+            renderer,
+            Scale::from(1.),
+            area,
+            area,
+            [1., 0., 0., 1.],
+            [0., 1., 0., 1.],
+            self.angle - FRAC_PI_2,
+        )
+        .into_iter()
+        .map(|elem| Box::new(elem) as _)
+        .collect()
+    }
+}

niri-visual-tests/src/cases/gradient_area.rs

@@ -0,0 +1,116 @@
+use std::f32::consts::{FRAC_PI_4, PI};
+use std::sync::atomic::Ordering;
+use std::time::Duration;
+
+use niri::animation::ANIMATION_SLOWDOWN;
+use niri::layout::focus_ring::FocusRing;
+use niri::render_helpers::gradient::GradientRenderElement;
+use niri_config::Color;
+use smithay::backend::renderer::element::RenderElement;
+use smithay::backend::renderer::gles::GlesRenderer;
+use smithay::utils::{Logical, Physical, Point, Rectangle, Scale, Size};
+
+use super::TestCase;
+
+pub struct GradientArea {
+    progress: f32,
+    border: FocusRing,
+    prev_time: Duration,
+}
+
+impl GradientArea {
+    pub fn new(_size: Size<i32, Logical>) -> Self {
+        let mut border = FocusRing::new(niri_config::FocusRing {
+            off: false,
+            width: 1,
+            active_color: Color::new(255, 255, 255, 128),
+            inactive_color: Color::default(),
+            active_gradient: None,
+            inactive_gradient: None,
+        });
+        border.set_active(true);
+
+        Self {
+            progress: 0.,
+            border,
+            prev_time: Duration::ZERO,
+        }
+    }
+}
+
+impl TestCase for GradientArea {
+    fn are_animations_ongoing(&self) -> bool {
+        true
+    }
+
+    fn advance_animations(&mut self, current_time: Duration) {
+        let mut delta = if self.prev_time.is_zero() {
+            Duration::ZERO
+        } else {
+            current_time.saturating_sub(self.prev_time)
+        };
+        self.prev_time = current_time;
+
+        let slowdown = ANIMATION_SLOWDOWN.load(Ordering::SeqCst);
+        if slowdown == 0. {
+            delta = Duration::ZERO
+        } else {
+            delta = delta.div_f64(slowdown);
+        }
+
+        self.progress += delta.as_secs_f32() * PI;
+
+        if self.progress >= PI * 2. {
+            self.progress -= PI * 2.
+        }
+    }
+
+    fn render(
+        &mut self,
+        renderer: &mut GlesRenderer,
+        size: Size<i32, Physical>,
+    ) -> Vec<Box<dyn RenderElement<GlesRenderer>>> {
+        let mut rv = Vec::new();
+
+        let f = (self.progress.sin() + 1.) / 2.;
+
+        let (a, b) = (size.w / 4, size.h / 4);
+        let rect_size = (size.w - a * 2, size.h - b * 2);
+        let area = Rectangle::from_loc_and_size((a, b), rect_size);
+
+        let g_size = Size::from((
+            (size.w as f32 / 8. + size.w as f32 / 8. * 7. * f).round() as i32,
+            (size.h as f32 / 8. + size.h as f32 / 8. * 7. * f).round() as i32,
+        ));
+        let g_loc = ((size.w - g_size.w) / 2, (size.h - g_size.h) / 2);
+        let g_area = Rectangle::from_loc_and_size(g_loc, g_size);
+
+        self.border.update(g_size, true);
+        rv.extend(
+            self.border
+                .render(
+                    renderer,
+                    Point::from(g_loc),
+                    Scale::from(1.),
+                    size.to_logical(1),
+                )
+                .map(|elem| Box::new(elem) as _),
+        );
+
+        rv.extend(
+            GradientRenderElement::new(
+                renderer,
+                Scale::from(1.),
+                area,
+                g_area,
+                [1., 0., 0., 1.],
+                [0., 1., 0., 1.],
+                FRAC_PI_4,
+            )
+            .into_iter()
+            .map(|elem| Box::new(elem) as _),
+        );
+
+        rv
+    }
+}

niri-visual-tests/src/cases/layout.rs

@@ -0,0 +1,233 @@
+use std::collections::HashMap;
+use std::time::Duration;
+
+use niri::layout::workspace::ColumnWidth;
+use niri::layout::{LayoutElement as _, Options};
+use niri::render_helpers::RenderTarget;
+use niri::utils::get_monotonic_time;
+use niri_config::Color;
+use smithay::backend::renderer::element::RenderElement;
+use smithay::backend::renderer::gles::GlesRenderer;
+use smithay::desktop::layer_map_for_output;
+use smithay::output::{Mode, Output, PhysicalProperties, Subpixel};
+use smithay::utils::{Logical, Physical, Size};
+
+use super::TestCase;
+use crate::test_window::TestWindow;
+
+type DynStepFn = Box<dyn FnOnce(&mut Layout)>;
+
+pub struct Layout {
+    output: Output,
+    windows: Vec<TestWindow>,
+    layout: niri::layout::Layout<TestWindow>,
+    start_time: Duration,
+    steps: HashMap<Duration, DynStepFn>,
+}
+
+impl Layout {
+    pub fn new(size: Size<i32, Logical>) -> Self {
+        let output = Output::new(
+            String::new(),
+            PhysicalProperties {
+                size: Size::from((size.w, size.h)),
+                subpixel: Subpixel::Unknown,
+                make: String::new(),
+                model: String::new(),
+            },
+        );
+        let mode = Some(Mode {
+            size: size.to_physical(1),
+            refresh: 60000,
+        });
+        output.change_current_state(mode, None, None, None);
+
+        let options = Options {
+            focus_ring: niri_config::FocusRing {
+                off: true,
+                ..Default::default()
+            },
+            border: niri_config::Border {
+                off: false,
+                width: 4,
+                active_color: Color::new(255, 163, 72, 255),
+                inactive_color: Color::new(50, 50, 50, 255),
+                active_gradient: None,
+                inactive_gradient: None,
+            },
+            ..Default::default()
+        };
+        let mut layout = niri::layout::Layout::with_options(options);
+        layout.add_output(output.clone());
+
+        Self {
+            output,
+            windows: Vec::new(),
+            layout,
+            start_time: get_monotonic_time(),
+            steps: HashMap::new(),
+        }
+    }
+
+    pub fn open_in_between(size: Size<i32, Logical>) -> Self {
+        let mut rv = Self::new(size);
+
+        rv.add_window(TestWindow::freeform(0), Some(ColumnWidth::Proportion(0.3)));
+        rv.add_window(TestWindow::freeform(1), Some(ColumnWidth::Proportion(0.3)));
+        rv.layout.activate_window(&0);
+
+        rv.add_step(500, |l| {
+            let win = TestWindow::freeform(2);
+            l.add_window(win.clone(), Some(ColumnWidth::Proportion(0.3)));
+            l.layout.start_open_animation_for_window(win.id());
+        });
+
+        rv
+    }
+
+    pub fn open_multiple_quickly(size: Size<i32, Logical>) -> Self {
+        let mut rv = Self::new(size);
+
+        for delay in [100, 200, 300] {
+            rv.add_step(delay, move |l| {
+                let win = TestWindow::freeform(delay as usize);
+                l.add_window(win.clone(), Some(ColumnWidth::Proportion(0.3)));
+                l.layout.start_open_animation_for_window(win.id());
+            });
+        }
+
+        rv
+    }
+
+    pub fn open_multiple_quickly_big(size: Size<i32, Logical>) -> Self {
+        let mut rv = Self::new(size);
+
+        for delay in [100, 200, 300] {
+            rv.add_step(delay, move |l| {
+                let win = TestWindow::freeform(delay as usize);
+                l.add_window(win.clone(), Some(ColumnWidth::Proportion(0.5)));
+                l.layout.start_open_animation_for_window(win.id());
+            });
+        }
+
+        rv
+    }
+
+    pub fn open_to_the_left(size: Size<i32, Logical>) -> Self {
+        let mut rv = Self::new(size);
+
+        rv.add_window(TestWindow::freeform(0), Some(ColumnWidth::Proportion(0.3)));
+        rv.add_window(TestWindow::freeform(1), Some(ColumnWidth::Proportion(0.3)));
+
+        rv.add_step(500, |l| {
+            let win = TestWindow::freeform(2);
+            let right_of = l.windows[0].clone();
+            l.add_window_right_of(&right_of, win.clone(), Some(ColumnWidth::Proportion(0.3)));
+            l.layout.start_open_animation_for_window(win.id());
+        });
+
+        rv
+    }
+
+    pub fn open_to_the_left_big(size: Size<i32, Logical>) -> Self {
+        let mut rv = Self::new(size);
+
+        rv.add_window(TestWindow::freeform(0), Some(ColumnWidth::Proportion(0.3)));
+        rv.add_window(TestWindow::freeform(1), Some(ColumnWidth::Proportion(0.8)));
+
+        rv.add_step(500, |l| {
+            let win = TestWindow::freeform(2);
+            let right_of = l.windows[0].clone();
+            l.add_window_right_of(&right_of, win.clone(), Some(ColumnWidth::Proportion(0.5)));
+            l.layout.start_open_animation_for_window(win.id());
+        });
+
+        rv
+    }
+
+    fn add_window(&mut self, mut window: TestWindow, width: Option<ColumnWidth>) {
+        let ws = self.layout.active_workspace().unwrap();
+        window.request_size(ws.new_window_size(width), false);
+        window.communicate();
+
+        self.layout.add_window(window.clone(), width, false);
+        self.windows.push(window);
+    }
+
+    fn add_window_right_of(
+        &mut self,
+        right_of: &TestWindow,
+        mut window: TestWindow,
+        width: Option<ColumnWidth>,
+    ) {
+        let ws = self.layout.active_workspace().unwrap();
+        window.request_size(ws.new_window_size(width), false);
+        window.communicate();
+
+        self.layout
+            .add_window_right_of(right_of.id(), window.clone(), width, false);
+        self.windows.push(window);
+    }
+
+    fn add_step(&mut self, delay_ms: u64, f: impl FnOnce(&mut Self) + 'static) {
+        self.steps
+            .insert(Duration::from_millis(delay_ms), Box::new(f) as _);
+    }
+}
+
+impl TestCase for Layout {
+    fn resize(&mut self, width: i32, height: i32) {
+        let mode = Some(Mode {
+            size: Size::from((width, height)),
+            refresh: 60000,
+        });
+        self.output.change_current_state(mode, None, None, None);
+        layer_map_for_output(&self.output).arrange();
+        self.layout.update_output_size(&self.output);
+        for win in &self.windows {
+            if win.communicate() {
+                self.layout.update_window(win.id());
+            }
+        }
+    }
+
+    fn are_animations_ongoing(&self) -> bool {
+        self.layout
+            .monitor_for_output(&self.output)
+            .unwrap()
+            .are_animations_ongoing()
+            || !self.steps.is_empty()
+    }
+
+    fn advance_animations(&mut self, mut current_time: Duration) {
+        let run = self
+            .steps
+            .keys()
+            .copied()
+            .filter(|delay| self.start_time + *delay <= current_time)
+            .collect::<Vec<_>>();
+        for key in &run {
+            let f = self.steps.remove(key).unwrap();
+            f(self);
+        }
+        if !run.is_empty() {
+            current_time = get_monotonic_time();
+        }
+
+        self.layout.advance_animations(current_time);
+    }
+
+    fn render(
+        &mut self,
+        renderer: &mut GlesRenderer,
+        _size: Size<i32, Physical>,
+    ) -> Vec<Box<dyn RenderElement<GlesRenderer>>> {
+        self.layout
+            .monitor_for_output(&self.output)
+            .unwrap()
+            .render_elements(renderer, RenderTarget::Output)
+            .into_iter()
+            .map(|elem| Box::new(elem) as _)
+            .collect()
+    }
+}

niri-visual-tests/src/cases/mod.rs

@@ -0,0 +1,24 @@
+use std::time::Duration;
+
+use smithay::backend::renderer::element::RenderElement;
+use smithay::backend::renderer::gles::GlesRenderer;
+use smithay::utils::{Physical, Size};
+
+pub mod gradient_angle;
+pub mod gradient_area;
+pub mod layout;
+pub mod tile;
+pub mod window;
+
+pub trait TestCase {
+    fn resize(&mut self, _width: i32, _height: i32) {}
+    fn are_animations_ongoing(&self) -> bool {
+        false
+    }
+    fn advance_animations(&mut self, _current_time: Duration) {}
+    fn render(
+        &mut self,
+        renderer: &mut GlesRenderer,
+        size: Size<i32, Physical>,
+    ) -> Vec<Box<dyn RenderElement<GlesRenderer>>>;
+}

niri-visual-tests/src/cases/tile.rs

@@ -0,0 +1,120 @@
+use std::rc::Rc;
+use std::time::Duration;
+
+use niri::layout::Options;
+use niri::render_helpers::RenderTarget;
+use niri_config::Color;
+use smithay::backend::renderer::element::RenderElement;
+use smithay::backend::renderer::gles::GlesRenderer;
+use smithay::utils::{Logical, Physical, Point, Scale, Size};
+
+use super::TestCase;
+use crate::test_window::TestWindow;
+
+pub struct Tile {
+    window: TestWindow,
+    tile: niri::layout::tile::Tile<TestWindow>,
+}
+
+impl Tile {
+    pub fn freeform(size: Size<i32, Logical>) -> Self {
+        let window = TestWindow::freeform(0);
+        let mut rv = Self::with_window(window);
+        rv.tile.request_tile_size(size, false);
+        rv.window.communicate();
+        rv
+    }
+
+    pub fn fixed_size(size: Size<i32, Logical>) -> Self {
+        let window = TestWindow::fixed_size(0);
+        let mut rv = Self::with_window(window);
+        rv.tile.request_tile_size(size, false);
+        rv.window.communicate();
+        rv
+    }
+
+    pub fn fixed_size_with_csd_shadow(size: Size<i32, Logical>) -> Self {
+        let window = TestWindow::fixed_size(0);
+        window.set_csd_shadow_width(64);
+        let mut rv = Self::with_window(window);
+        rv.tile.request_tile_size(size, false);
+        rv.window.communicate();
+        rv
+    }
+
+    pub fn freeform_open(size: Size<i32, Logical>) -> Self {
+        let mut rv = Self::freeform(size);
+        rv.window.set_color([0.1, 0.1, 0.1, 1.]);
+        rv.tile.start_open_animation();
+        rv
+    }
+
+    pub fn fixed_size_open(size: Size<i32, Logical>) -> Self {
+        let mut rv = Self::fixed_size(size);
+        rv.window.set_color([0.1, 0.1, 0.1, 1.]);
+        rv.tile.start_open_animation();
+        rv
+    }
+
+    pub fn fixed_size_with_csd_shadow_open(size: Size<i32, Logical>) -> Self {
+        let mut rv = Self::fixed_size_with_csd_shadow(size);
+        rv.window.set_color([0.1, 0.1, 0.1, 1.]);
+        rv.tile.start_open_animation();
+        rv
+    }
+
+    pub fn with_window(window: TestWindow) -> Self {
+        let options = Options {
+            focus_ring: niri_config::FocusRing {
+                off: true,
+                ..Default::default()
+            },
+            border: niri_config::Border {
+                off: false,
+                width: 32,
+                active_color: Color::new(255, 163, 72, 255),
+                ..Default::default()
+            },
+            ..Default::default()
+        };
+        let tile = niri::layout::tile::Tile::new(window.clone(), Rc::new(options));
+        Self { window, tile }
+    }
+}
+
+impl TestCase for Tile {
+    fn resize(&mut self, width: i32, height: i32) {
+        self.tile
+            .request_tile_size(Size::from((width, height)), false);
+        self.window.communicate();
+    }
+
+    fn are_animations_ongoing(&self) -> bool {
+        self.tile.are_animations_ongoing()
+    }
+
+    fn advance_animations(&mut self, current_time: Duration) {
+        self.tile.advance_animations(current_time, true);
+    }
+
+    fn render(
+        &mut self,
+        renderer: &mut GlesRenderer,
+        size: Size<i32, Physical>,
+    ) -> Vec<Box<dyn RenderElement<GlesRenderer>>> {
+        let tile_size = self.tile.tile_size().to_physical(1);
+        let location = Point::from(((size.w - tile_size.w) / 2, (size.h - tile_size.h) / 2));
+
+        self.tile
+            .render(
+                renderer,
+                location,
+                Scale::from(1.),
+                size.to_logical(1),
+                true,
+                RenderTarget::Output,
+            )
+            .map(|elem| Box::new(elem) as _)
+            .collect()
+    }
+}

niri-visual-tests/src/cases/window.rs

@@ -0,0 +1,64 @@
+use niri::layout::LayoutElement;
+use niri::render_helpers::RenderTarget;
+use smithay::backend::renderer::element::RenderElement;
+use smithay::backend::renderer::gles::GlesRenderer;
+use smithay::utils::{Logical, Physical, Point, Scale, Size};
+
+use super::TestCase;
+use crate::test_window::TestWindow;
+
+pub struct Window {
+    window: TestWindow,
+}
+
+impl Window {
+    pub fn freeform(size: Size<i32, Logical>) -> Self {
+        let mut window = TestWindow::freeform(0);
+        window.request_size(size, false);
+        window.communicate();
+        Self { window }
+    }
+
+    pub fn fixed_size(size: Size<i32, Logical>) -> Self {
+        let mut window = TestWindow::fixed_size(0);
+        window.request_size(size, false);
+        window.communicate();
+        Self { window }
+    }
+
+    pub fn fixed_size_with_csd_shadow(size: Size<i32, Logical>) -> Self {
+        let mut window = TestWindow::fixed_size(0);
+        window.set_csd_shadow_width(64);
+        window.request_size(size, false);
+        window.communicate();
+        Self { window }
+    }
+}
+
+impl TestCase for Window {
+    fn resize(&mut self, width: i32, height: i32) {
+        self.window.request_size(Size::from((width, height)), false);
+        self.window.communicate();
+    }
+
+    fn render(
+        &mut self,
+        renderer: &mut GlesRenderer,
+        size: Size<i32, Physical>,
+    ) -> Vec<Box<dyn RenderElement<GlesRenderer>>> {
+        let win_size = self.window.size().to_physical(1);
+        let location = Point::from(((size.w - win_size.w) / 2, (size.h - win_size.h) / 2));
+
+        self.window
+            .render(
+                renderer,
+                location,
+                Scale::from(1.),
+                1.,
+                RenderTarget::Output,
+            )
+            .into_iter()
+            .map(|elem| Box::new(elem) as _)
+            .collect()
+    }
+}

niri-visual-tests/src/main.rs

@@ -0,0 +1,170 @@
+#[macro_use]
+extern crate tracing;
+
+use std::env;
+use std::sync::atomic::Ordering;
+
+use adw::prelude::{AdwApplicationWindowExt, NavigationPageExt};
+use cases::tile::Tile;
+use cases::window::Window;
+use gtk::prelude::{
+    AdjustmentExt, ApplicationExt, ApplicationExtManual, BoxExt, GtkWindowExt, WidgetExt,
+};
+use gtk::{gdk, gio, glib};
+use niri::animation::ANIMATION_SLOWDOWN;
+use smithay::utils::{Logical, Size};
+use smithay_view::SmithayView;
+use tracing_subscriber::EnvFilter;
+
+use crate::cases::gradient_angle::GradientAngle;
+use crate::cases::gradient_area::GradientArea;
+use crate::cases::layout::Layout;
+use crate::cases::TestCase;
+
+mod cases;
+mod smithay_view;
+mod test_window;
+
+fn main() -> glib::ExitCode {
+    let directives =
+        env::var("RUST_LOG").unwrap_or_else(|_| "niri-visual-tests=debug,niri=debug".to_owned());
+    let env_filter = EnvFilter::builder().parse_lossy(directives);
+    tracing_subscriber::fmt()
+        .compact()
+        .with_env_filter(env_filter)
+        .init();
+
+    let app = adw::Application::new(None::<&str>, gio::ApplicationFlags::NON_UNIQUE);
+    app.connect_startup(on_startup);
+    app.connect_activate(build_ui);
+    app.run()
+}
+
+fn on_startup(_app: &adw::Application) {
+    // Load our CSS.
+    let provider = gtk::CssProvider::new();
+    provider.load_from_string(include_str!("../resources/style.css"));
+    if let Some(display) = gdk::Display::default() {
+        gtk::style_context_add_provider_for_display(
+            &display,
+            &provider,
+            gtk::STYLE_PROVIDER_PRIORITY_APPLICATION,
+        );
+    }
+}
+
+fn build_ui(app: &adw::Application) {
+    let stack = gtk::Stack::new();
+
+    struct S {
+        stack: gtk::Stack,
+    }
+
+    impl S {
+        fn add<T: TestCase + 'static>(
+            &self,
+            make: impl Fn(Size<i32, Logical>) -> T + 'static,
+            title: &str,
+        ) {
+            let view = SmithayView::new(make);
+            self.stack.add_titled(&view, None, title);
+        }
+    }
+
+    let s = S {
+        stack: stack.clone(),
+    };
+
+    s.add(Window::freeform, "Freeform Window");
+    s.add(Window::fixed_size, "Fixed Size Window");
+    s.add(
+        Window::fixed_size_with_csd_shadow,
+        "Fixed Size Window - CSD Shadow",
+    );
+
+    s.add(Tile::freeform, "Freeform Tile");
+    s.add(Tile::fixed_size, "Fixed Size Tile");
+    s.add(
+        Tile::fixed_size_with_csd_shadow,
+        "Fixed Size Tile - CSD Shadow",
+    );
+    s.add(Tile::freeform_open, "Freeform Tile - Open");
+    s.add(Tile::fixed_size_open, "Fixed Size Tile - Open");
+    s.add(
+        Tile::fixed_size_with_csd_shadow_open,
+        "Fixed Size Tile - CSD Shadow - Open",
+    );
+
+    s.add(Layout::open_in_between, "Layout - Open In-Between");
+    s.add(
+        Layout::open_multiple_quickly,
+        "Layout - Open Multiple Quickly",
+    );
+    s.add(
+        Layout::open_multiple_quickly_big,
+        "Layout - Open Multiple Quickly - Big",
+    );
+    s.add(Layout::open_to_the_left, "Layout - Open To The Left");
+    s.add(
+        Layout::open_to_the_left_big,
+        "Layout - Open To The Left - Big",
+    );
+
+    s.add(GradientAngle::new, "Gradient - Angle");
+    s.add(GradientArea::new, "Gradient - Area");
+
+    let content_headerbar = adw::HeaderBar::new();
+
+    let anim_adjustment = gtk::Adjustment::new(1., 0., 10., 0.1, 0.5, 0.);
+    anim_adjustment
+        .connect_value_changed(|adj| ANIMATION_SLOWDOWN.store(adj.value(), Ordering::SeqCst));
+    let anim_scale = gtk::Scale::new(gtk::Orientation::Horizontal, Some(&anim_adjustment));
+    anim_scale.set_hexpand(true);
+
+    let anim_control_bar = gtk::Box::new(gtk::Orientation::Horizontal, 6);
+    anim_control_bar.add_css_class("anim-control-bar");
+    anim_control_bar.append(&gtk::Label::new(Some("Slowdown")));
+    anim_control_bar.append(&anim_scale);
+
+    let content_view = adw::ToolbarView::new();
+    content_view.set_top_bar_style(adw::ToolbarStyle::RaisedBorder);
+    content_view.set_bottom_bar_style(adw::ToolbarStyle::RaisedBorder);
+    content_view.add_top_bar(&content_headerbar);
+    content_view.add_bottom_bar(&anim_control_bar);
+    content_view.set_content(Some(&stack));
+    let content = adw::NavigationPage::new(
+        &content_view,
+        stack
+            .page(&stack.visible_child().unwrap())
+            .title()
+            .as_deref()
+            .unwrap(),
+    );
+
+    let sidebar_header = adw::HeaderBar::new();
+    let stack_sidebar = gtk::StackSidebar::new();
+    stack_sidebar.set_stack(&stack);
+    let sidebar_view = adw::ToolbarView::new();
+    sidebar_view.add_top_bar(&sidebar_header);
+    sidebar_view.set_content(Some(&stack_sidebar));
+    let sidebar = adw::NavigationPage::new(&sidebar_view, "Tests");
+
+    let split_view = adw::NavigationSplitView::new();
+    split_view.set_content(Some(&content));
+    split_view.set_sidebar(Some(&sidebar));
+
+    stack.connect_visible_child_notify(move |stack| {
+        content.set_title(
+            stack
+                .visible_child()
+                .and_then(|c| stack.page(&c).title())
+                .as_deref()
+                .unwrap_or_default(),
+        )
+    });
+
+    let window = adw::ApplicationWindow::new(app);
+    window.set_title(Some("niri visual tests"));
+    window.set_content(Some(&split_view));
+    window.present();
+}

niri-visual-tests/src/smithay_view.rs

@@ -0,0 +1,251 @@
+use gtk::glib;
+use gtk::subclass::prelude::*;
+use smithay::utils::{Logical, Size};
+
+use crate::cases::TestCase;
+
+mod imp {
+    use std::cell::{Cell, OnceCell, RefCell};
+    use std::ptr::null;
+
+    use anyhow::{ensure, Context};
+    use gtk::gdk;
+    use gtk::prelude::*;
+    use niri::render_helpers::{resources, shaders};
+    use niri::utils::get_monotonic_time;
+    use smithay::backend::egl::ffi::egl;
+    use smithay::backend::egl::EGLContext;
+    use smithay::backend::renderer::gles::{Capability, GlesRenderer};
+    use smithay::backend::renderer::{Frame, Renderer, Unbind};
+    use smithay::utils::{Physical, Rectangle, Scale, Transform};
+
+    use super::*;
+
+    type DynMakeTestCase = Box<dyn Fn(Size<i32, Logical>) -> Box<dyn TestCase>>;
+
+    #[derive(Default)]
+    pub struct SmithayView {
+        gl_area: gtk::GLArea,
+        size: Cell<(i32, i32)>,
+        renderer: RefCell<Option<Result<GlesRenderer, ()>>>,
+        pub make_test_case: OnceCell<DynMakeTestCase>,
+        test_case: RefCell<Option<Box<dyn TestCase>>>,
+    }
+
+    #[glib::object_subclass]
+    impl ObjectSubclass for SmithayView {
+        const NAME: &'static str = "NiriSmithayView";
+        type Type = super::SmithayView;
+        type ParentType = gtk::Widget;
+
+        fn class_init(klass: &mut Self::Class) {
+            klass.set_layout_manager_type::<gtk::BinLayout>();
+        }
+    }
+
+    impl ObjectImpl for SmithayView {
+        fn constructed(&self) {
+            let obj = self.obj();
+
+            self.parent_constructed();
+
+            self.gl_area.set_allowed_apis(gdk::GLAPI::GLES);
+            self.gl_area.set_parent(&*obj);
+
+            self.gl_area.connect_resize({
+                let imp = self.downgrade();
+                move |_, width, height| {
+                    if let Some(imp) = imp.upgrade() {
+                        imp.resize(width, height);
+                    }
+                }
+            });
+
+            self.gl_area.connect_render({
+                let imp = self.downgrade();
+                move |_, gl_context| {
+                    if let Some(imp) = imp.upgrade() {
+                        if let Err(err) = imp.render(gl_context) {
+                            warn!("error rendering: {err:?}");
+                        }
+                    }
+                    glib::Propagation::Stop
+                }
+            });
+
+            obj.add_tick_callback(|obj, _frame_clock| {
+                let imp = obj.imp();
+
+                if let Some(case) = &mut *imp.test_case.borrow_mut() {
+                    if case.are_animations_ongoing() {
+                        imp.gl_area.queue_draw();
+                    }
+                }
+
+                glib::ControlFlow::Continue
+            });
+        }
+
+        fn dispose(&self) {
+            self.gl_area.unparent();
+        }
+    }
+
+    impl WidgetImpl for SmithayView {
+        fn unmap(&self) {
+            self.test_case.replace(None);
+            self.parent_unmap();
+        }
+
+        fn unrealize(&self) {
+            self.renderer.replace(None);
+            self.parent_unrealize();
+        }
+    }
+
+    impl SmithayView {
+        fn resize(&self, width: i32, height: i32) {
+            self.size.set((width, height));
+
+            if let Some(case) = &mut *self.test_case.borrow_mut() {
+                case.resize(width, height);
+            }
+        }
+
+        fn render(&self, _gl_context: &gdk::GLContext) -> anyhow::Result<()> {
+            // Set up the Smithay renderer.
+            let mut renderer = self.renderer.borrow_mut();
+            let renderer = renderer.get_or_insert_with(|| {
+                unsafe { create_renderer() }
+                    .map_err(|err| warn!("error creating a Smithay renderer: {err:?}"))
+            });
+            let Ok(renderer) = renderer else {
+                return Ok(());
+            };
+
+            let size = self.size.get();
+
+            // Create the test case if missing.
+            let mut case = self.test_case.borrow_mut();
+            let case = case.get_or_insert_with(|| {
+                let make = self.make_test_case.get().unwrap();
+                make(Size::from(size))
+            });
+
+            case.advance_animations(get_monotonic_time());
+
+            let rect: Rectangle<i32, Physical> = Rectangle::from_loc_and_size((0, 0), size);
+
+            let elements = unsafe {
+                with_framebuffer_save_restore(renderer, |renderer| {
+                    case.render(renderer, Size::from(size))
+                })
+            }?;
+
+            let mut frame = renderer
+                .render(rect.size, Transform::Normal)
+                .context("error creating frame")?;
+
+            frame
+                .clear([0.3, 0.3, 0.3, 1.], &[rect])
+                .context("error clearing")?;
+
+            for element in elements.iter().rev() {
+                let src = element.src();
+                let dst = element.geometry(Scale::from(1.));
+
+                if let Some(mut damage) = rect.intersection(dst) {
+                    damage.loc -= dst.loc;
+                    element
+                        .draw(&mut frame, src, dst, &[damage])
+                        .context("error drawing element")?;
+                }
+            }
+
+            Ok(())
+        }
+    }
+
+    unsafe fn create_renderer() -> anyhow::Result<GlesRenderer> {
+        smithay::backend::egl::ffi::make_sure_egl_is_loaded()
+            .context("error loading EGL symbols in Smithay")?;
+
+        let egl_display = egl::GetCurrentDisplay();
+        ensure!(egl_display != egl::NO_DISPLAY, "no current EGL display");
+
+        let egl_context = egl::GetCurrentContext();
+        ensure!(egl_context != egl::NO_CONTEXT, "no current EGL context");
+
+        // There's no config ID on the EGL context and there's no current EGL surface, but we don't
+        // really use it anyway so just get some random one.
+        let mut egl_config_id = null();
+        let mut num_configs = 0;
+        let res = egl::GetConfigs(egl_display, &mut egl_config_id, 1, &mut num_configs);
+        ensure!(res == egl::TRUE, "error choosing EGL config");
+        ensure!(num_configs != 0, "no EGL config");
+
+        let egl_context = EGLContext::from_raw(egl_display, egl_config_id as *const _, egl_context)
+            .context("error creating EGL context")?;
+        let capabilities = GlesRenderer::supported_capabilities(&egl_context)
+            .context("error getting supported renderer capabilities")?
+            .into_iter()
+            .filter(|c| *c != Capability::ColorTransformations);
+
+        let mut renderer = GlesRenderer::with_capabilities(egl_context, capabilities)
+            .context("error creating GlesRenderer")?;
+
+        resources::init(&mut renderer);
+        shaders::init(&mut renderer);
+
+        Ok(renderer)
+    }
+
+    unsafe fn with_framebuffer_save_restore<T>(
+        renderer: &mut GlesRenderer,
+        f: impl FnOnce(&mut GlesRenderer) -> T,
+    ) -> anyhow::Result<T> {
+        let mut framebuffer = 0;
+        renderer
+            .with_context(|gl| unsafe {
+                gl.GetIntegerv(
+                    smithay::backend::renderer::gles::ffi::FRAMEBUFFER_BINDING,
+                    &mut framebuffer,
+                );
+            })
+            .context("error running closure in GL context")?;
+        ensure!(framebuffer != 0, "error getting the framebuffer");
+
+        let rv = f(renderer);
+
+        renderer.unbind().context("error unbinding")?;
+        renderer
+            .with_context(|gl| unsafe {
+                gl.BindFramebuffer(
+                    smithay::backend::renderer::gles::ffi::FRAMEBUFFER,
+                    framebuffer as u32,
+                );
+            })
+            .context("error running closure in GL context")?;
+
+        Ok(rv)
+    }
+}
+
+glib::wrapper! {
+    pub struct SmithayView(ObjectSubclass<imp::SmithayView>)
+        @extends gtk::Widget;
+}
+
+impl SmithayView {
+    pub fn new<T: TestCase + 'static>(
+        make_test_case: impl Fn(Size<i32, Logical>) -> T + 'static,
+    ) -> Self {
+        let obj: Self = glib::Object::builder().build();
+
+        let make = move |size| Box::new(make_test_case(size)) as Box<dyn TestCase>;
+        let make_test_case = Box::new(make) as _;
+        let _ = obj.imp().make_test_case.set(make_test_case);
+
+        obj
+    }
+}

niri-visual-tests/src/test_window.rs

@@ -0,0 +1,241 @@
+use std::cell::RefCell;
+use std::cmp::{max, min};
+use std::rc::Rc;
+
+use niri::layout::{LayoutElement, LayoutElementRenderElement, LayoutElementRenderSnapshot};
+use niri::render_helpers::renderer::NiriRenderer;
+use niri::render_helpers::RenderTarget;
+use niri::window::ResolvedWindowRules;
+use smithay::backend::renderer::element::solid::{SolidColorBuffer, SolidColorRenderElement};
+use smithay::backend::renderer::element::{Id, Kind};
+use smithay::output::Output;
+use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
+use smithay::utils::{Logical, Point, Scale, Size, Transform};
+
+#[derive(Debug)]
+struct TestWindowInner {
+    size: Size<i32, Logical>,
+    requested_size: Option<Size<i32, Logical>>,
+    min_size: Size<i32, Logical>,
+    max_size: Size<i32, Logical>,
+    buffer: SolidColorBuffer,
+    pending_fullscreen: bool,
+    csd_shadow_width: i32,
+    csd_shadow_buffer: SolidColorBuffer,
+}
+
+#[derive(Debug, Clone)]
+pub struct TestWindow {
+    id: usize,
+    inner: Rc<RefCell<TestWindowInner>>,
+}
+
+impl TestWindow {
+    pub fn freeform(id: usize) -> Self {
+        let size = Size::from((100, 200));
+        let min_size = Size::from((0, 0));
+        let max_size = Size::from((0, 0));
+        let buffer = SolidColorBuffer::new(size, [0.15, 0.64, 0.41, 1.]);
+
+        Self {
+            id,
+            inner: Rc::new(RefCell::new(TestWindowInner {
+                size,
+                requested_size: None,
+                min_size,
+                max_size,
+                buffer,
+                pending_fullscreen: false,
+                csd_shadow_width: 0,
+                csd_shadow_buffer: SolidColorBuffer::new((0, 0), [0., 0., 0., 0.3]),
+            })),
+        }
+    }
+
+    pub fn fixed_size(id: usize) -> Self {
+        let rv = Self::freeform(id);
+        rv.set_min_size((200, 400).into());
+        rv.set_max_size((200, 400).into());
+        rv.set_color([0.88, 0.11, 0.14, 1.]);
+        rv.communicate();
+        rv
+    }
+
+    pub fn set_min_size(&self, size: Size<i32, Logical>) {
+        self.inner.borrow_mut().min_size = size;
+    }
+
+    pub fn set_max_size(&self, size: Size<i32, Logical>) {
+        self.inner.borrow_mut().max_size = size;
+    }
+
+    pub fn set_color(&self, color: [f32; 4]) {
+        self.inner.borrow_mut().buffer.set_color(color);
+    }
+
+    pub fn set_csd_shadow_width(&self, width: i32) {
+        self.inner.borrow_mut().csd_shadow_width = width;
+    }
+
+    pub fn communicate(&self) -> bool {
+        let mut rv = false;
+        let mut inner = self.inner.borrow_mut();
+
+        let mut new_size = inner.size;
+
+        if let Some(size) = inner.requested_size.take() {
+            assert!(size.w >= 0);
+            assert!(size.h >= 0);
+
+            if size.w != 0 {
+                new_size.w = size.w;
+            }
+            if size.h != 0 {
+                new_size.h = size.h;
+            }
+        }
+
+        if inner.max_size.w > 0 {
+            new_size.w = min(new_size.w, inner.max_size.w);
+        }
+        if inner.max_size.h > 0 {
+            new_size.h = min(new_size.h, inner.max_size.h);
+        }
+        if inner.min_size.w > 0 {
+            new_size.w = max(new_size.w, inner.min_size.w);
+        }
+        if inner.min_size.h > 0 {
+            new_size.h = max(new_size.h, inner.min_size.h);
+        }
+
+        if inner.size != new_size {
+            inner.size = new_size;
+            inner.buffer.resize(new_size);
+            rv = true;
+        }
+
+        let mut csd_shadow_size = new_size;
+        csd_shadow_size.w += inner.csd_shadow_width * 2;
+        csd_shadow_size.h += inner.csd_shadow_width * 2;
+        inner.csd_shadow_buffer.resize(csd_shadow_size);
+
+        rv
+    }
+}
+
+impl LayoutElement for TestWindow {
+    type Id = usize;
+
+    fn id(&self) -> &Self::Id {
+        &self.id
+    }
+
+    fn size(&self) -> Size<i32, Logical> {
+        self.inner.borrow().size
+    }
+
+    fn buf_loc(&self) -> Point<i32, Logical> {
+        (0, 0).into()
+    }
+
+    fn is_in_input_region(&self, _point: Point<f64, Logical>) -> bool {
+        false
+    }
+
+    fn render<R: NiriRenderer>(
+        &self,
+        _renderer: &mut R,
+        location: Point<i32, Logical>,
+        scale: Scale<f64>,
+        alpha: f32,
+        _target: RenderTarget,
+    ) -> Vec<LayoutElementRenderElement<R>> {
+        let inner = self.inner.borrow();
+
+        vec![
+            SolidColorRenderElement::from_buffer(
+                &inner.buffer,
+                location.to_physical_precise_round(scale),
+                scale,
+                alpha,
+                Kind::Unspecified,
+            )
+            .into(),
+            SolidColorRenderElement::from_buffer(
+                &inner.csd_shadow_buffer,
+                (location - Point::from((inner.csd_shadow_width, inner.csd_shadow_width)))
+                    .to_physical_precise_round(scale),
+                scale,
+                alpha,
+                Kind::Unspecified,
+            )
+            .into(),
+        ]
+    }
+
+    fn request_size(&mut self, size: Size<i32, Logical>, _animate: bool) {
+        self.inner.borrow_mut().requested_size = Some(size);
+        self.inner.borrow_mut().pending_fullscreen = false;
+    }
+
+    fn request_fullscreen(&self, _size: Size<i32, Logical>) {
+        self.inner.borrow_mut().pending_fullscreen = true;
+    }
+
+    fn min_size(&self) -> Size<i32, Logical> {
+        self.inner.borrow().min_size
+    }
+
+    fn max_size(&self) -> Size<i32, Logical> {
+        self.inner.borrow().max_size
+    }
+
+    fn is_wl_surface(&self, _wl_surface: &WlSurface) -> bool {
+        false
+    }
+
+    fn set_preferred_scale_transform(&self, _scale: i32, _transform: Transform) {}
+
+    fn has_ssd(&self) -> bool {
+        false
+    }
+
+    fn output_enter(&self, _output: &Output) {}
+
+    fn output_leave(&self, _output: &Output) {}
+
+    fn set_offscreen_element_id(&self, _id: Option<Id>) {}
+
+    fn set_activated(&mut self, _active: bool) {}
+
+    fn set_bounds(&self, _bounds: Size<i32, Logical>) {}
+
+    fn send_pending_configure(&mut self) {}
+
+    fn is_fullscreen(&self) -> bool {
+        false
+    }
+
+    fn is_pending_fullscreen(&self) -> bool {
+        self.inner.borrow().pending_fullscreen
+    }
+
+    fn refresh(&self) {}
+
+    fn rules(&self) -> &ResolvedWindowRules {
+        static EMPTY: ResolvedWindowRules = ResolvedWindowRules::empty();
+        &EMPTY
+    }
+
+    fn take_unmap_snapshot(&self) -> Option<LayoutElementRenderSnapshot> {
+        None
+    }
+
+    fn animation_snapshot(&self) -> Option<&LayoutElementRenderSnapshot> {
+        None
+    }
+
+    fn take_animation_snapshot(&mut self) -> Option<LayoutElementRenderSnapshot> {
+        None
+    }
+}

resources/default-config.kdl

@@ -1,6 +1,11 @@
 // This config is in the KDL format: https://kdl.dev
 // "/-" comments out the following node.
+// Check the wiki for a full description of the configuration:
+// https://github.com/YaLTeR/niri/wiki/Configuration:-Overview
 
+// Input device configuration.
+// Find the full list of options on the wiki:
+// https://github.com/YaLTeR/niri/wiki/Configuration:-Input
 input {
     keyboard {
         xkb {
@@ -11,16 +16,6 @@ input {
             // layout "us,ru"
             // options "grp:win_space_toggle,compose:ralt,ctrl:nocaps"
         }
-
-        // You can set the keyboard repeat parameters. The defaults match wlroots and sway.
-        // Delay is in milliseconds before the repeat starts. Rate is in characters per second.
-        // repeat-delay 600
-        // repeat-rate 25
-
-        // Niri can remember the keyboard layout globally (the default) or per-window.
-        // - "global" - layout change is global for all windows.
-        // - "window" - layout is tracked for each window individually.
-        // track-layout "global"
     }
 
     // Next sections include libinput settings.
@@ -28,10 +23,10 @@ input {
     touchpad {
         tap
         // dwt
+        // dwtp
         natural-scroll
         // accel-speed 0.2
         // accel-profile "flat"
-        // tap-button-map "left-middle-right"
     }
 
     mouse {
@@ -40,86 +35,73 @@ input {
         // accel-profile "flat"
     }
 
-    tablet {
+    // Uncomment this to make the mouse warp to the center of newly focused windows.
-        // Set the name of the output (see below) which the tablet will map to.
+    // warp-mouse-to-focus
-        // If this is unset or the output doesn't exist, the tablet maps to one of the
-        // existing outputs.
-        map-to-output "eDP-1"
-    }
 
-    // By default, niri will take over the power button to make it sleep
+    // Focus windows and outputs automatically when moving the mouse into them.
-    // instead of power off.
+    // focus-follows-mouse
-    // Uncomment this if you would like to configure the power button elsewhere
-    // (i.e. logind.conf).
-    // disable-power-key-handling
 }
 
 // You can configure outputs by their name, which you can find
 // by running `niri msg outputs` while inside a niri instance.
 // The built-in laptop monitor is usually called "eDP-1".
-// Remember to uncommend the node by removing "/-"!
+// Find more information on the wiki:
+// https://github.com/YaLTeR/niri/wiki/Configuration:-Outputs
+// Remember to uncomment the node by removing "/-"!
 /-output "eDP-1" {
     // Uncomment this line to disable this output.
     // off
 
-    // Scale is a floating-point number, but at the moment only integer values work.
-    scale 2.0
-
     // Resolution and, optionally, refresh rate of the output.
     // The format is "<width>x<height>" or "<width>x<height>@<refresh rate>".
     // If the refresh rate is omitted, niri will pick the highest refresh rate
     // for the resolution.
     // If the mode is omitted altogether or is invalid, niri will pick one automatically.
     // Run `niri msg outputs` while inside a niri instance to list all outputs and their modes.
-    mode "1920x1080@144"
+    mode "1920x1080@120.030"
+
+    // Scale is a floating-point number, but at the moment only integer values work.
+    scale 2.0
+
+    // Transform allows to rotate the output counter-clockwise, valid values are:
+    // normal, 90, 180, 270, flipped, flipped-90, flipped-180 and flipped-270.
+    transform "normal"
 
     // Position of the output in the global coordinate space.
     // This affects directional monitor actions like "focus-monitor-left", and cursor movement.
     // The cursor can only move between directly adjacent outputs.
-    // Output scale has to be taken into account for positioning:
+    // Output scale and rotation has to be taken into account for positioning:
     // outputs are sized in logical, or scaled, pixels.
     // For example, a 3840×2160 output with scale 2.0 will have a logical size of 1920×1080,
     // so to put another output directly adjacent to it on the right, set its x to 1920.
-    // It the position is unset or results in an overlap, the output is instead placed
+    // If the position is unset or results in an overlap, the output is instead placed
     // automatically.
     position x=1280 y=0
 }
 
+// Settings that influence how windows are positioned and sized.
+// Find more information on the wiki:
+// https://github.com/YaLTeR/niri/wiki/Configuration:-Layout
 layout {
-    // You can change how the focus ring looks.
+    // Set gaps around windows in logical pixels.
-    focus-ring {
+    gaps 16
-        // Uncomment this line to disable the focus ring.
-        // off
 
-        // How many logical pixels the ring extends out from the windows.
+    // When to center a column when changing focus, options are:
-        width 4
+    // - "never", default behavior, focusing an off-screen column will keep at the left
-
+    //   or right edge of the screen.
-        // Color of the ring on the active monitor: red, green, blue, alpha.
+    // - "always", the focused column will always be centered.
-        active-color 127 200 255 255
+    // - "on-overflow", focusing a column will center it if it doesn't fit
-
+    //   together with the previously focused column.
-        // Color of the ring on inactive monitors: red, green, blue, alpha.
+    center-focused-column "never"
-        inactive-color 80 80 80 255
-    }
-
-    // You can also add a border. It's similar to the focus ring, but always visible.
-    border {
-        // The settings are the same as for the focus ring.
-        // If you enable the border, you probably want to disable the focus ring.
-        off
-
-        width 4
-        active-color 255 200 127 255
-        inactive-color 80 80 80 255
-    }
 
     // You can customize the widths that "switch-preset-column-width" (Mod+R) toggles between.
     preset-column-widths {
         // Proportion sets the width as a fraction of the output width, taking gaps into account.
         // For example, you can perfectly fit four windows sized "proportion 0.25" on an output.
         // The default preset widths are 1/3, 1/2 and 2/3 of the output.
-        proportion 0.333
+        proportion 0.33333
         proportion 0.5
-        proportion 0.667
+        proportion 0.66667
 
         // Fixed sets the width in logical pixels exactly.
         // fixed 1920
@@ -130,8 +112,64 @@ layout {
     // If you leave the brackets empty, the windows themselves will decide their initial width.
     // default-column-width {}
 
-    // Set gaps around windows in logical pixels.
+    // By default focus ring and border are rendered as a solid background rectangle
-    gaps 16
+    // behind windows. That is, they will show up through semitransparent windows.
+    // This is because windows using client-side decorations can have an arbitrary shape.
+    //
+    // If you don't like that, you should uncomment `prefer-no-csd` below.
+    // Niri will draw focus ring and border *around* windows that agree to omit their
+    // client-side decorations.
+    //
+    // Alternatively, you can override it with a window rule called
+    // `draw-border-with-background`.
+
+    // You can change how the focus ring looks.
+    focus-ring {
+        // Uncomment this line to disable the focus ring.
+        // off
+
+        // How many logical pixels the ring extends out from the windows.
+        width 4
+
+        // Colors can be set in a variety of ways:
+        // - CSS named colors: "red"
+        // - RGB hex: "#rgb", "#rgba", "#rrggbb", "#rrggbbaa"
+        // - CSS-like notation: "rgb(255, 127, 0)", rgba(), hsl() and a few others.
+
+        // Color of the ring on the active monitor.
+        active-color "#7fc8ff"
+
+        // Color of the ring on inactive monitors.
+        inactive-color "#505050"
+
+        // You can also use gradients. They take precedence over solid colors.
+        // Gradients are rendered the same as CSS linear-gradient(angle, from, to).
+        // The angle is the same as in linear-gradient, and is optional,
+        // defaulting to 180 (top-to-bottom gradient).
+        // You can use any CSS linear-gradient tool on the web to set these up.
+        //
+        // active-gradient from="#80c8ff" to="#bbddff" angle=45
+
+        // You can also color the gradient relative to the entire view
+        // of the workspace, rather than relative to just the window itself.
+        // To do that, set relative-to="workspace-view".
+        //
+        // inactive-gradient from="#505050" to="#808080" angle=45 relative-to="workspace-view"
+    }
+
+    // You can also add a border. It's similar to the focus ring, but always visible.
+    border {
+        // The settings are the same as for the focus ring.
+        // If you enable the border, you probably want to disable the focus ring.
+        off
+
+        width 4
+        active-color "#ffc87f"
+        inactive-color "#505050"
+
+        // active-gradient from="#ffbb66" to="#ffc880" angle=45 relative-to="workspace-view"
+        // inactive-gradient from="#505050" to="#808080" angle=45 relative-to="workspace-view"
+    }
 
     // Struts shrink the area occupied by windows, similarly to layer-shell panels.
     // You can think of them as a kind of outer gaps. They are set in logical pixels.
@@ -144,14 +182,6 @@ layout {
         // top 64
         // bottom 64
     }
-
-    // When to center a column when changing focus, options are:
-    // - "never", default behavior, focusing an off-screen column will keep at the left
-    //   or right edge of the screen.
-    // - "on-overflow", focusing a column will center it if it doesn't fit
-    //   together with the previously focused column.
-    // - "always", the focused column will always be centered.
-    center-focused-column "never"
 }
 
 // Add lines like this to spawn processes at startup.
@@ -159,13 +189,6 @@ layout {
 // which may be more convenient to use.
 // spawn-at-startup "alacritty" "-e" "fish"
 
-cursor {
-    // Change the theme and size of the cursor as well as set the
-    // `XCURSOR_THEME` and `XCURSOR_SIZE` env variables.
-    // xcursor-theme "default"
-    // xcursor-size 24
-}
-
 // Uncomment this line to ask the clients to omit their client-side decorations if possible.
 // If the client will specifically ask for CSD, the request will be honored.
 // Additionally, clients will be informed that they are tiled, removing some rounded corners.
@@ -179,10 +202,41 @@ screenshot-path "~/Pictures/Screenshots/Screenshot from %Y-%m-%d %H-%M-%S.png"
 // You can also set this to null to disable saving screenshots to disk.
 // screenshot-path null
 
-// Settings for the "Important Hotkeys" overlay.
+// Animation settings.
-hotkey-overlay {
+// The wiki explains how to configure individual animations:
-    // Uncomment this line if you don't want to see the hotkey help at niri startup.
+// https://github.com/YaLTeR/niri/wiki/Configuration:-Animations
-    // skip-at-startup
+animations {
+    // Uncomment to turn off all animations.
+    // off
+
+    // Slow down all animations by this factor. Values below 1 speed them up instead.
+    // slowdown 3.0
+}
+
+// Window rules let you adjust behavior for individual windows.
+// Find more information on the wiki:
+// https://github.com/YaLTeR/niri/wiki/Configuration:-Window-Rules
+
+// Work around WezTerm's initial configure bug
+// by setting an empty default-column-width.
+window-rule {
+    // This regular expression is intentionally made as specific as possible,
+    // since this is the default config, and we want no false positives.
+    // You can get away with just app-id="wezterm" if you want.
+    match app-id=r#"^org\.wezfurlong\.wezterm$"#
+    default-column-width {}
+}
+
+// Example: block out two password managers from screen capture.
+// (This example rule is commented out with a "/-" in front.)
+/-window-rule {
+    match app-id=r#"^org\.keepassxc\.KeePassXC$"#
+    match app-id=r#"^org\.gnome\.World\.Secrets$"#
+
+    block-out-from "screen-capture"
+
+    // Use this instead if you want them visible on third-party screenshot tools.
+    // block-out-from "screencast"
 }
 
 binds {
@@ -192,6 +246,9 @@ binds {
     //
     // "Mod" is a special modifier equal to Super when running on a TTY, and to Alt
     // when running as a winit window.
+    //
+    // Most actions that you can bind here can also be invoked programmatically with
+    // `niri msg action do-something`.
 
     // Mod-Shift-/, which is usually the same as Mod-?,
     // shows a list of important hotkeys.
@@ -200,14 +257,17 @@ binds {
     // Suggested binds for running programs: terminal, app launcher, screen locker.
     Mod+T { spawn "alacritty"; }
     Mod+D { spawn "fuzzel"; }
-    Mod+Alt+L { spawn "swaylock"; }
+    Super+Alt+L { spawn "swaylock"; }
 
     // You can also use a shell:
     // Mod+T { spawn "bash" "-c" "notify-send hello && exec alacritty"; }
 
     // Example volume keys mappings for PipeWire & WirePlumber.
-    XF86AudioRaiseVolume { spawn "wpctl" "set-volume" "@DEFAULT_AUDIO_SINK@" "0.1+"; }
+    // The allow-when-locked=true property makes them work even when the session is locked.
-    XF86AudioLowerVolume { spawn "wpctl" "set-volume" "@DEFAULT_AUDIO_SINK@" "0.1-"; }
+    XF86AudioRaiseVolume allow-when-locked=true { spawn "wpctl" "set-volume" "@DEFAULT_AUDIO_SINK@" "0.1+"; }
+    XF86AudioLowerVolume allow-when-locked=true { spawn "wpctl" "set-volume" "@DEFAULT_AUDIO_SINK@" "0.1-"; }
+    XF86AudioMute        allow-when-locked=true { spawn "wpctl" "set-mute" "@DEFAULT_AUDIO_SINK@" "toggle"; }
+    XF86AudioMicMute     allow-when-locked=true { spawn "wpctl" "set-mute" "@DEFAULT_AUDIO_SOURCE@" "toggle"; }
 
     Mod+Q { close-window; }
 
@@ -263,6 +323,10 @@ binds {
     // Mod+Shift+Ctrl+Left  { move-window-to-monitor-left; }
     // ...
 
+    // And you can also move a whole workspace to another monitor:
+    // Mod+Shift+Ctrl+Left  { move-workspace-to-monitor-left; }
+    // ...
+
     Mod+Page_Down      { focus-workspace-down; }
     Mod+Page_Up        { focus-workspace-up; }
     Mod+U              { focus-workspace-down; }
@@ -281,6 +345,46 @@ binds {
     Mod+Shift+U         { move-workspace-down; }
     Mod+Shift+I         { move-workspace-up; }
 
+    // You can bind mouse wheel scroll ticks using the following syntax.
+    // These binds will change direction based on the natural-scroll setting.
+    //
+    // To avoid scrolling through workspaces really fast, you can use
+    // the cooldown-ms property. The bind will be rate-limited to this value.
+    // You can set a cooldown on any bind, but it's most useful for the wheel.
+    Mod+WheelScrollDown      cooldown-ms=150 { focus-workspace-down; }
+    Mod+WheelScrollUp        cooldown-ms=150 { focus-workspace-up; }
+    Mod+Ctrl+WheelScrollDown cooldown-ms=150 { move-column-to-workspace-down; }
+    Mod+Ctrl+WheelScrollUp   cooldown-ms=150 { move-column-to-workspace-up; }
+
+    Mod+WheelScrollRight      { focus-column-right; }
+    Mod+WheelScrollLeft       { focus-column-left; }
+    Mod+Ctrl+WheelScrollRight { move-column-right; }
+    Mod+Ctrl+WheelScrollLeft  { move-column-left; }
+
+    // Usually scrolling up and down with Shift in applications results in
+    // horizontal scrolling; these binds replicate that.
+    Mod+Shift+WheelScrollDown      { focus-column-right; }
+    Mod+Shift+WheelScrollUp        { focus-column-left; }
+    Mod+Ctrl+Shift+WheelScrollDown { move-column-right; }
+    Mod+Ctrl+Shift+WheelScrollUp   { move-column-left; }
+
+    // Similarly, you can bind touchpad scroll "ticks".
+    // Touchpad scrolling is continuous, so for these binds it is split into
+    // discrete intervals.
+    // These binds are also affected by touchpad's natural-scroll, so these
+    // example binds are "inverted", since we have natural-scroll enabled for
+    // touchpads by default.
+    // Mod+TouchpadScrollDown { spawn "wpctl" "set-volume" "@DEFAULT_AUDIO_SINK@" "0.02+"; }
+    // Mod+TouchpadScrollUp   { spawn "wpctl" "set-volume" "@DEFAULT_AUDIO_SINK@" "0.02-"; }
+
+    // You can refer to workspaces by index. However, keep in mind that
+    // niri is a dynamic workspace system, so these commands are kind of
+    // "best effort". Trying to refer to a workspace index bigger than
+    // the current workspace count will instead refer to the bottommost
+    // (empty) workspace.
+    //
+    // For example, with 2 workspaces + 1 empty, indices 3, 4, 5 and so on
+    // will all refer to the 3rd workspace.
     Mod+1 { focus-workspace 1; }
     Mod+2 { focus-workspace 2; }
     Mod+3 { focus-workspace 3; }
@@ -303,9 +407,16 @@ binds {
     // Alternatively, there are commands to move just a single window:
     // Mod+Ctrl+1 { move-window-to-workspace 1; }
 
+    // Switches focus between the current and the previous workspace.
+    // Mod+Tab { focus-workspace-previous; }
+
     Mod+Comma  { consume-window-into-column; }
     Mod+Period { expel-window-from-column; }
 
+    // There are also commands that consume or expel a single window to the side.
+    // Mod+BracketLeft  { consume-or-expel-window-left; }
+    // Mod+BracketRight { consume-or-expel-window-right; }
+
     Mod+R { switch-preset-column-width; }
     Mod+F { maximize-column; }
     Mod+Shift+F { fullscreen-window; }
@@ -338,35 +449,10 @@ binds {
     Ctrl+Print { screenshot-screen; }
     Alt+Print { screenshot-window; }
 
+    // The quit action will show a confirmation dialog to avoid accidental exits.
     Mod+Shift+E { quit; }
+
+    // Powers off the monitors. To turn them back on, do any input like
+    // moving the mouse or pressing any other key.
     Mod+Shift+P { power-off-monitors; }
-
-    Mod+Shift+Ctrl+T { toggle-debug-tint; }
-}
-
-// Settings for debugging. Not meant for normal use.
-// These can change or stop working at any point with little notice.
-debug {
-    // Make niri take over its DBus services even if it's not running as a session.
-    // Useful for testing screen recording changes without having to relogin.
-    // The main niri instance will *not* currently take back the services; so you will
-    // need to relogin in the end.
-    // dbus-interfaces-in-non-session-instances
-
-    // Wait until every frame is done rendering before handing it over to DRM.
-    // wait-for-frame-completion-before-queueing
-
-    // Enable direct scanout into overlay planes.
-    // May cause frame drops during some animations on some hardware.
-    // enable-overlay-planes
-
-    // Disable the use of the cursor plane.
-    // The cursor will be rendered together with the rest of the frame.
-    // disable-cursor-plane
-
-    // Slow down animations by this factor.
-    // animation-slowdown 3.0
-
-    // Override the DRM device that niri will use for all rendering.
-    // render-drm-device "/dev/dri/renderD129"
 }

resources/niri-session

@@ -20,12 +20,6 @@ fi
 # Reset failed state of all user units.
 systemctl --user reset-failed
 
-# Set the current desktop for xdg-desktop-portal.
-export XDG_CURRENT_DESKTOP=niri
-
-# Ensure the session type is set to Wayland for xdg-autostart apps.
-export XDG_SESSION_TYPE=wayland
-
 # Import the login manager environment.
 systemctl --user import-environment
 
@@ -44,4 +38,4 @@ systemctl --user --wait start niri.service
 systemctl --user start --job-mode=replace-irreversibly niri-shutdown.target
 
 # Unset environment that we've set.
-systemctl --user unset-environment WAYLAND_DISPLAY XDG_SESSION_TYPE XDG_CURRENT_DESKTOP
+systemctl --user unset-environment WAYLAND_DISPLAY XDG_SESSION_TYPE XDG_CURRENT_DESKTOP NIRI_SOCKET

resources/niri.service

@@ -9,5 +9,6 @@ Wants=xdg-desktop-autostart.target
 Before=xdg-desktop-autostart.target
 
 [Service]
+Slice=session.slice
 Type=notify
-ExecStart=/usr/bin/niri
+ExecStart=/usr/bin/niri --session

src/animation.rs

@@ -1,58 +0,0 @@
-use std::time::Duration;
-
-use keyframe::functions::EaseOutCubic;
-use keyframe::EasingFunction;
-use portable_atomic::{AtomicF64, Ordering};
-
-use crate::utils::get_monotonic_time;
-
-pub static ANIMATION_SLOWDOWN: AtomicF64 = AtomicF64::new(1.);
-
-#[derive(Debug)]
-pub struct Animation {
-    from: f64,
-    to: f64,
-    duration: Duration,
-    start_time: Duration,
-    current_time: Duration,
-}
-
-impl Animation {
-    pub fn new(from: f64, to: f64, over: Duration) -> Self {
-        // FIXME: ideally we shouldn't use current time here because animations started within the
-        // same frame cycle should have the same start time to be synchronized.
-        let now = get_monotonic_time();
-
-        Self {
-            from,
-            to,
-            duration: over.mul_f64(ANIMATION_SLOWDOWN.load(Ordering::Relaxed)),
-            start_time: now,
-            current_time: now,
-        }
-    }
-
-    pub fn set_current_time(&mut self, time: Duration) {
-        self.current_time = time;
-    }
-
-    pub fn is_done(&self) -> bool {
-        self.current_time >= self.start_time + self.duration
-    }
-
-    pub fn value(&self) -> f64 {
-        let passed = (self.current_time - self.start_time).as_secs_f64();
-        let total = self.duration.as_secs_f64();
-        let x = (passed / total).clamp(0., 1.);
-        EaseOutCubic.y(x) * (self.to - self.from) + self.from
-    }
-
-    pub fn to(&self) -> f64 {
-        self.to
-    }
-
-    #[cfg(test)]
-    pub fn from(&self) -> f64 {
-        self.from
-    }
-}

src/animation/mod.rs

@@ -0,0 +1,376 @@
+use std::time::Duration;
+
+use keyframe::functions::{EaseOutCubic, EaseOutQuad};
+use keyframe::EasingFunction;
+use portable_atomic::{AtomicF64, Ordering};
+
+use crate::utils::get_monotonic_time;
+
+mod spring;
+pub use spring::{Spring, SpringParams};
+
+pub static ANIMATION_SLOWDOWN: AtomicF64 = AtomicF64::new(1.);
+
+#[derive(Debug)]
+pub struct Animation {
+    from: f64,
+    to: f64,
+    initial_velocity: f64,
+    is_off: bool,
+    duration: Duration,
+    /// Time until the animation first reaches `to`.
+    ///
+    /// Best effort; not always exactly precise.
+    clamped_duration: Duration,
+    start_time: Duration,
+    current_time: Duration,
+    kind: Kind,
+}
+
+#[derive(Debug, Clone, Copy)]
+enum Kind {
+    Easing {
+        curve: Curve,
+    },
+    Spring(Spring),
+    Deceleration {
+        initial_velocity: f64,
+        deceleration_rate: f64,
+    },
+}
+
+#[derive(Debug, Clone, Copy)]
+pub enum Curve {
+    EaseOutQuad,
+    EaseOutCubic,
+    EaseOutExpo,
+}
+
+impl Animation {
+    pub fn new(from: f64, to: f64, initial_velocity: f64, config: niri_config::Animation) -> Self {
+        // Scale the velocity by slowdown to keep the touchpad gestures feeling right.
+        let initial_velocity = initial_velocity * ANIMATION_SLOWDOWN.load(Ordering::Relaxed);
+
+        let mut rv = Self::ease(from, to, initial_velocity, 0, Curve::EaseOutCubic);
+        if config.off {
+            rv.is_off = true;
+            return rv;
+        }
+
+        rv.replace_config(config);
+        rv
+    }
+
+    pub fn replace_config(&mut self, config: niri_config::Animation) {
+        self.is_off = config.off;
+        if config.off {
+            self.duration = Duration::ZERO;
+            self.clamped_duration = Duration::ZERO;
+            return;
+        }
+
+        let start_time = self.start_time;
+        let current_time = self.current_time;
+
+        match config.kind {
+            niri_config::AnimationKind::Spring(p) => {
+                let params = SpringParams::new(p.damping_ratio, f64::from(p.stiffness), p.epsilon);
+
+                let spring = Spring {
+                    from: self.from,
+                    to: self.to,
+                    initial_velocity: self.initial_velocity,
+                    params,
+                };
+                *self = Self::spring(spring);
+            }
+            niri_config::AnimationKind::Easing(p) => {
+                *self = Self::ease(
+                    self.from,
+                    self.to,
+                    self.initial_velocity,
+                    u64::from(p.duration_ms),
+                    Curve::from(p.curve),
+                );
+            }
+        }
+
+        self.start_time = start_time;
+        self.current_time = current_time;
+    }
+
+    /// Restarts the animation using the previous config.
+    pub fn restarted(self, from: f64, to: f64, initial_velocity: f64) -> Self {
+        if self.is_off {
+            return self;
+        }
+
+        // Scale the velocity by slowdown to keep the touchpad gestures feeling right.
+        let initial_velocity = initial_velocity * ANIMATION_SLOWDOWN.load(Ordering::Relaxed);
+
+        match self.kind {
+            Kind::Easing { curve } => Self::ease(
+                from,
+                to,
+                initial_velocity,
+                self.duration.as_millis() as u64,
+                curve,
+            ),
+            Kind::Spring(spring) => {
+                let spring = Spring {
+                    from: self.from,
+                    to: self.to,
+                    initial_velocity: self.initial_velocity,
+                    params: spring.params,
+                };
+                Self::spring(spring)
+            }
+            Kind::Deceleration {
+                initial_velocity,
+                deceleration_rate,
+            } => {
+                let threshold = 0.001; // FIXME
+                Self::decelerate(from, initial_velocity, deceleration_rate, threshold)
+            }
+        }
+    }
+
+    pub fn ease(from: f64, to: f64, initial_velocity: f64, duration_ms: u64, curve: Curve) -> Self {
+        // FIXME: ideally we shouldn't use current time here because animations started within the
+        // same frame cycle should have the same start time to be synchronized.
+        let now = get_monotonic_time();
+
+        let duration = Duration::from_millis(duration_ms);
+        let kind = Kind::Easing { curve };
+
+        Self {
+            from,
+            to,
+            initial_velocity,
+            is_off: false,
+            duration,
+            // Our current curves never overshoot.
+            clamped_duration: duration,
+            start_time: now,
+            current_time: now,
+            kind,
+        }
+    }
+
+    pub fn spring(spring: Spring) -> Self {
+        let _span = tracy_client::span!("Animation::spring");
+
+        // FIXME: ideally we shouldn't use current time here because animations started within the
+        // same frame cycle should have the same start time to be synchronized.
+        let now = get_monotonic_time();
+
+        let duration = spring.duration();
+        let clamped_duration = spring.clamped_duration().unwrap_or(duration);
+        let kind = Kind::Spring(spring);
+
+        Self {
+            from: spring.from,
+            to: spring.to,
+            initial_velocity: spring.initial_velocity,
+            is_off: false,
+            duration,
+            clamped_duration,
+            start_time: now,
+            current_time: now,
+            kind,
+        }
+    }
+
+    pub fn decelerate(
+        from: f64,
+        initial_velocity: f64,
+        deceleration_rate: f64,
+        threshold: f64,
+    ) -> Self {
+        // FIXME: ideally we shouldn't use current time here because animations started within the
+        // same frame cycle should have the same start time to be synchronized.
+        let now = get_monotonic_time();
+
+        let duration_s = if initial_velocity == 0. {
+            0.
+        } else {
+            let coeff = 1000. * deceleration_rate.ln();
+            (-coeff * threshold / initial_velocity.abs()).ln() / coeff
+        };
+        let duration = Duration::from_secs_f64(duration_s);
+
+        let to = from - initial_velocity / (1000. * deceleration_rate.ln());
+
+        let kind = Kind::Deceleration {
+            initial_velocity,
+            deceleration_rate,
+        };
+
+        Self {
+            from,
+            to,
+            initial_velocity,
+            is_off: false,
+            duration,
+            clamped_duration: duration,
+            start_time: now,
+            current_time: now,
+            kind,
+        }
+    }
+
+    pub fn set_current_time(&mut self, time: Duration) {
+        if self.duration.is_zero() {
+            self.current_time = time;
+            return;
+        }
+
+        let end_time = self.start_time + self.duration;
+        if end_time <= self.current_time {
+            return;
+        }
+
+        let slowdown = ANIMATION_SLOWDOWN.load(Ordering::Relaxed);
+        if slowdown <= f64::EPSILON {
+            // Zero slowdown will cause the animation to end right away.
+            self.current_time = end_time;
+            return;
+        }
+
+        // We can't change current_time (since the incoming time values are always real-time), so
+        // apply the slowdown by shifting the start time to compensate.
+        if self.current_time <= time {
+            let delta = time - self.current_time;
+
+            let max_delta = end_time - self.current_time;
+            let min_slowdown = delta.as_secs_f64() / max_delta.as_secs_f64();
+            if slowdown <= min_slowdown {
+                // Our slowdown value will cause the animation to end right away.
+                self.current_time = end_time;
+                return;
+            }
+
+            let adjusted_delta = delta.div_f64(slowdown);
+            if adjusted_delta >= delta {
+                self.start_time -= adjusted_delta - delta;
+            } else {
+                self.start_time += delta - adjusted_delta;
+            }
+        } else {
+            let delta = self.current_time - time;
+
+            let min_slowdown = delta.as_secs_f64() / self.current_time.as_secs_f64();
+            if slowdown <= min_slowdown {
+                // Current time was about to jump to before the animation had started; let's just
+                // cancel the animation in this case.
+                self.current_time = end_time;
+                return;
+            }
+
+            let adjusted_delta = delta.div_f64(slowdown);
+            if adjusted_delta >= delta {
+                self.start_time += adjusted_delta - delta;
+            } else {
+                self.start_time -= delta - adjusted_delta;
+            }
+        }
+
+        self.current_time = time;
+    }
+
+    pub fn is_done(&self) -> bool {
+        self.current_time >= self.start_time + self.duration
+    }
+
+    pub fn is_clamped_done(&self) -> bool {
+        self.current_time >= self.start_time + self.clamped_duration
+    }
+
+    pub fn value(&self) -> f64 {
+        if self.is_done() {
+            return self.to;
+        }
+
+        let passed = self.current_time - self.start_time;
+
+        match self.kind {
+            Kind::Easing { curve } => {
+                let passed = passed.as_secs_f64();
+                let total = self.duration.as_secs_f64();
+                let x = (passed / total).clamp(0., 1.);
+                curve.y(x) * (self.to - self.from) + self.from
+            }
+            Kind::Spring(spring) => {
+                let value = spring.value_at(passed);
+
+                // Protect against numerical instability.
+                let range = (self.to - self.from) * 10.;
+                let a = self.from - range;
+                let b = self.to + range;
+                if self.from <= self.to {
+                    value.clamp(a, b)
+                } else {
+                    value.clamp(b, a)
+                }
+            }
+            Kind::Deceleration {
+                initial_velocity,
+                deceleration_rate,
+            } => {
+                let passed = passed.as_secs_f64();
+                let coeff = 1000. * deceleration_rate.ln();
+                self.from + (deceleration_rate.powf(1000. * passed) - 1.) / coeff * initial_velocity
+            }
+        }
+    }
+
+    /// Returns a value that stops at the target value after first reaching it.
+    ///
+    /// Best effort; not always exactly precise.
+    pub fn clamped_value(&self) -> f64 {
+        if self.is_clamped_done() {
+            return self.to;
+        }
+
+        self.value()
+    }
+
+    pub fn to(&self) -> f64 {
+        self.to
+    }
+
+    #[cfg(test)]
+    pub fn from(&self) -> f64 {
+        self.from
+    }
+
+    pub fn offset(&mut self, offset: f64) {
+        self.from += offset;
+        self.to += offset;
+
+        if let Kind::Spring(spring) = &mut self.kind {
+            spring.from += offset;
+            spring.to += offset;
+        }
+    }
+}
+
+impl Curve {
+    pub fn y(self, x: f64) -> f64 {
+        match self {
+            Curve::EaseOutQuad => EaseOutQuad.y(x),
+            Curve::EaseOutCubic => EaseOutCubic.y(x),
+            Curve::EaseOutExpo => 1. - 2f64.powf(-10. * x),
+        }
+    }
+}
+
+impl From<niri_config::AnimationCurve> for Curve {
+    fn from(value: niri_config::AnimationCurve) -> Self {
+        match value {
+            niri_config::AnimationCurve::EaseOutQuad => Curve::EaseOutQuad,
+            niri_config::AnimationCurve::EaseOutCubic => Curve::EaseOutCubic,
+            niri_config::AnimationCurve::EaseOutExpo => Curve::EaseOutExpo,
+        }
+    }
+}

src/animation/spring.rs

@@ -0,0 +1,168 @@
+use std::time::Duration;
+
+#[derive(Debug, Clone, Copy)]
+pub struct SpringParams {
+    pub damping: f64,
+    pub mass: f64,
+    pub stiffness: f64,
+    pub epsilon: f64,
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct Spring {
+    pub from: f64,
+    pub to: f64,
+    pub initial_velocity: f64,
+    pub params: SpringParams,
+}
+
+impl SpringParams {
+    pub fn new(damping_ratio: f64, stiffness: f64, epsilon: f64) -> Self {
+        let damping_ratio = damping_ratio.max(0.);
+        let stiffness = stiffness.max(0.);
+        let epsilon = epsilon.max(0.);
+
+        let mass = 1.;
+        let critical_damping = 2. * (mass * stiffness).sqrt();
+        let damping = damping_ratio * critical_damping;
+
+        Self {
+            damping,
+            mass,
+            stiffness,
+            epsilon,
+        }
+    }
+}
+
+impl Spring {
+    pub fn value_at(&self, t: Duration) -> f64 {
+        self.oscillate(t.as_secs_f64())
+    }
+
+    // Based on libadwaita (LGPL-2.1-or-later):
+    // https://gitlab.gnome.org/GNOME/libadwaita/-/blob/1.4.4/src/adw-spring-animation.c,
+    // which itself is based on (MIT):
+    // https://github.com/robb/RBBAnimation/blob/master/RBBAnimation/RBBSpringAnimation.m
+    /// Computes and returns the duration until the spring is at rest.
+    pub fn duration(&self) -> Duration {
+        const DELTA: f64 = 0.001;
+
+        let beta = self.params.damping / (2. * self.params.mass);
+
+        if beta.abs() <= f64::EPSILON || beta < 0. {
+            return Duration::MAX;
+        }
+
+        let omega0 = (self.params.stiffness / self.params.mass).sqrt();
+
+        // As first ansatz for the overdamped solution,
+        // and general estimation for the oscillating ones
+        // we take the value of the envelope when it's < epsilon.
+        let mut x0 = -self.params.epsilon.ln() / beta;
+
+        // f64::EPSILON is too small for this specific comparison, so we use
+        // f32::EPSILON even though it's doubles.
+        if (beta - omega0).abs() <= f64::from(f32::EPSILON) || beta < omega0 {
+            return Duration::from_secs_f64(x0);
+        }
+
+        // Since the overdamped solution decays way slower than the envelope
+        // we need to use the value of the oscillation itself.
+        // Newton's root finding method is a good candidate in this particular case:
+        // https://en.wikipedia.org/wiki/Newton%27s_method
+        let mut y0 = self.oscillate(x0);
+        let m = (self.oscillate(x0 + DELTA) - y0) / DELTA;
+
+        let mut x1 = (self.to - y0 + m * x0) / m;
+        let mut y1 = self.oscillate(x1);
+
+        let mut i = 0;
+        while (self.to - y1).abs() > self.params.epsilon {
+            if i > 1000 {
+                return Duration::ZERO;
+            }
+
+            x0 = x1;
+            y0 = y1;
+
+            let m = (self.oscillate(x0 + DELTA) - y0) / DELTA;
+
+            x1 = (self.to - y0 + m * x0) / m;
+            y1 = self.oscillate(x1);
+            i += 1;
+        }
+
+        Duration::from_secs_f64(x1)
+    }
+
+    /// Computes and returns the duration until the spring reaches its target position.
+    pub fn clamped_duration(&self) -> Option<Duration> {
+        let beta = self.params.damping / (2. * self.params.mass);
+
+        if beta.abs() <= f64::EPSILON || beta < 0. {
+            return Some(Duration::MAX);
+        }
+
+        if (self.to - self.from).abs() <= f64::EPSILON {
+            return Some(Duration::ZERO);
+        }
+
+        // The first frame is not that important and we avoid finding the trivial 0 for in-place
+        // animations.
+        let mut i = 1u16;
+        let mut y = self.oscillate(f64::from(i) / 1000.);
+
+        while (self.to - self.from > f64::EPSILON && self.to - y > self.params.epsilon)
+            || (self.from - self.to > f64::EPSILON && y - self.to > self.params.epsilon)
+        {
+            if i > 3000 {
+                return None;
+            }
+
+            i += 1;
+            y = self.oscillate(f64::from(i) / 1000.);
+        }
+
+        Some(Duration::from_millis(u64::from(i)))
+    }
+
+    /// Returns the spring position at a given time in seconds.
+    fn oscillate(&self, t: f64) -> f64 {
+        let b = self.params.damping;
+        let m = self.params.mass;
+        let k = self.params.stiffness;
+        let v0 = self.initial_velocity;
+
+        let beta = b / (2. * m);
+        let omega0 = (k / m).sqrt();
+
+        let x0 = self.from - self.to;
+
+        let envelope = (-beta * t).exp();
+
+        // Solutions of the form C1*e^(lambda1*x) + C2*e^(lambda2*x)
+        // for the differential equation m*ẍ+b*ẋ+kx = 0
+
+        // f64::EPSILON is too small for this specific comparison, so we use
+        // f32::EPSILON even though it's doubles.
+        if (beta - omega0).abs() <= f64::from(f32::EPSILON) {
+            // Critically damped.
+            self.to + envelope * (x0 + (beta * x0 + v0) * t)
+        } else if beta < omega0 {
+            // Underdamped.
+            let omega1 = ((omega0 * omega0) - (beta * beta)).sqrt();
+
+            self.to
+                + envelope
+                    * (x0 * (omega1 * t).cos() + ((beta * x0 + v0) / omega1) * (omega1 * t).sin())
+        } else {
+            // Overdamped.
+            let omega2 = ((beta * beta) - (omega0 * omega0)).sqrt();
+
+            self.to
+                + envelope
+                    * (x0 * (omega2 * t).cosh() + ((beta * x0 + v0) / omega2) * (omega2 * t).sinh())
+        }
+    }
+}

src/backend/mod.rs

@@ -1,6 +1,4 @@
-use std::cell::RefCell;
 use std::collections::HashMap;
-use std::rc::Rc;
 use std::sync::{Arc, Mutex};
 use std::time::Duration;
 
@@ -10,7 +8,7 @@ use smithay::output::Output;
 use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
 
 use crate::input::CompositorMod;
-use crate::Niri;
+use crate::niri::Niri;
 
 pub mod tty;
 pub use tty::Tty;
@@ -33,6 +31,8 @@ pub enum RenderResult {
     Skipped,
 }
 
+pub type IpcOutputMap = HashMap<String, niri_ipc::Output>;
+
 impl Backend {
     pub fn init(&mut self, niri: &mut Niri) {
         match self {
@@ -98,7 +98,7 @@ impl Backend {
         }
     }
 
-    pub fn import_dmabuf(&mut self, dmabuf: &Dmabuf) -> Result<(), ()> {
+    pub fn import_dmabuf(&mut self, dmabuf: &Dmabuf) -> bool {
         match self {
             Backend::Tty(tty) => tty.import_dmabuf(dmabuf),
             Backend::Winit(winit) => winit.import_dmabuf(dmabuf),
@@ -112,21 +112,13 @@ impl Backend {
         }
     }
 
-    pub fn ipc_outputs(&self) -> Rc<RefCell<HashMap<String, niri_ipc::Output>>> {
+    pub fn ipc_outputs(&self) -> Arc<Mutex<IpcOutputMap>> {
         match self {
             Backend::Tty(tty) => tty.ipc_outputs(),
             Backend::Winit(winit) => winit.ipc_outputs(),
         }
     }
 
-    #[cfg_attr(not(feature = "dbus"), allow(unused))]
-    pub fn enabled_outputs(&self) -> Arc<Mutex<HashMap<String, Output>>> {
-        match self {
-            Backend::Tty(tty) => tty.enabled_outputs(),
-            Backend::Winit(winit) => winit.enabled_outputs(),
-        }
-    }
-
     #[cfg(feature = "xdp-gnome-screencast")]
     pub fn gbm_device(
         &self,
@@ -138,7 +130,7 @@ impl Backend {
         }
     }
 
-    pub fn set_monitors_active(&self, active: bool) {
+    pub fn set_monitors_active(&mut self, active: bool) {
         match self {
             Backend::Tty(tty) => tty.set_monitors_active(active),
             Backend::Winit(_) => (),

src/backend/winit.rs

@@ -16,29 +16,30 @@ use smithay::reexports::calloop::LoopHandle;
 use smithay::reexports::wayland_protocols::wp::presentation_time::server::wp_presentation_feedback;
 use smithay::reexports::winit::dpi::LogicalSize;
 use smithay::reexports::winit::window::WindowBuilder;
-use smithay::utils::Transform;
 
-use super::RenderResult;
+use super::{IpcOutputMap, RenderResult};
-use crate::niri::{RedrawState, State};
+use crate::niri::{Niri, RedrawState, State};
-use crate::utils::get_monotonic_time;
+use crate::render_helpers::{resources, shaders, RenderTarget};
-use crate::Niri;
+use crate::utils::{get_monotonic_time, logical_output};
 
 pub struct Winit {
     config: Rc<RefCell<Config>>,
     output: Output,
     backend: WinitGraphicsBackend<GlesRenderer>,
     damage_tracker: OutputDamageTracker,
-    ipc_outputs: Rc<RefCell<HashMap<String, niri_ipc::Output>>>,
+    ipc_outputs: Arc<Mutex<IpcOutputMap>>,
-    enabled_outputs: Arc<Mutex<HashMap<String, Output>>>,
 }
 
 impl Winit {
-    pub fn new(config: Rc<RefCell<Config>>, event_loop: LoopHandle<State>) -> Self {
+    pub fn new(
+        config: Rc<RefCell<Config>>,
+        event_loop: LoopHandle<State>,
+    ) -> Result<Self, winit::Error> {
         let builder = WindowBuilder::new()
             .with_inner_size(LogicalSize::new(1280.0, 800.0))
             // .with_resizable(false)
             .with_title("niri");
-        let (backend, winit) = winit::init_from_builder(builder).unwrap();
+        let (backend, winit) = winit::init_from_builder(builder)?;
 
         let output = Output::new(
             "winit".to_string(),
@@ -54,11 +55,11 @@ impl Winit {
             size: backend.window_size(),
             refresh: 60_000,
         };
-        output.change_current_state(Some(mode), Some(Transform::Flipped180), None, None);
+        output.change_current_state(Some(mode), None, None, None);
         output.set_preferred(mode);
 
         let physical_properties = output.physical_properties();
-        let ipc_outputs = Rc::new(RefCell::new(HashMap::from([(
+        let ipc_outputs = Arc::new(Mutex::new(HashMap::from([(
             "winit".to_owned(),
             niri_ipc::Output {
                 name: output.name(),
@@ -69,16 +70,15 @@ impl Winit {
                     width: backend.window_size().w.clamp(0, u16::MAX as i32) as u16,
                     height: backend.window_size().h.clamp(0, u16::MAX as i32) as u16,
                     refresh_rate: 60_000,
+                    is_preferred: true,
                 }],
                 current_mode: Some(0),
+                vrr_supported: false,
+                vrr_enabled: false,
+                logical: Some(logical_output(&output)),
             },
         )])));
 
-        let enabled_outputs = Arc::new(Mutex::new(HashMap::from([(
-            "winit".to_owned(),
-            output.clone(),
-        )])));
-
         let damage_tracker = OutputDamageTracker::from_output(&output);
 
         event_loop
@@ -95,45 +95,47 @@ impl Winit {
                         None,
                     );
 
-                    let mut ipc_outputs = winit.ipc_outputs.borrow_mut();
+                    {
-                    let mode = &mut ipc_outputs.get_mut("winit").unwrap().modes[0];
+                        let mut ipc_outputs = winit.ipc_outputs.lock().unwrap();
-                    mode.width = size.w.clamp(0, u16::MAX as i32) as u16;
+                        let output = ipc_outputs.get_mut("winit").unwrap();
-                    mode.height = size.h.clamp(0, u16::MAX as i32) as u16;
+                        let mode = &mut output.modes[0];
+                        mode.width = size.w.clamp(0, u16::MAX as i32) as u16;
+                        mode.height = size.h.clamp(0, u16::MAX as i32) as u16;
+                        if let Some(logical) = output.logical.as_mut() {
+                            logical.width = size.w as u32;
+                            logical.height = size.h as u32;
+                        }
+                        state.niri.ipc_outputs_changed = true;
+                    }
 
-                    state.niri.output_resized(winit.output.clone());
+                    state.niri.output_resized(&winit.output);
                 }
                 WinitEvent::Input(event) => state.process_input_event(event),
                 WinitEvent::Focus(_) => (),
-                WinitEvent::Redraw => state
+                WinitEvent::Redraw => state.niri.queue_redraw(&state.backend.winit().output),
-                    .niri
+                WinitEvent::CloseRequested => state.niri.stop_signal.stop(),
-                    .queue_redraw(state.backend.winit().output.clone()),
-                WinitEvent::CloseRequested => {
-                    state.niri.stop_signal.stop();
-                    state.niri.remove_output(&state.backend.winit().output);
-                }
             })
             .unwrap();
 
-        Self {
+        Ok(Self {
             config,
             output,
             backend,
             damage_tracker,
             ipc_outputs,
-            enabled_outputs,
+        })
-        }
     }
 
     pub fn init(&mut self, niri: &mut Niri) {
-        if let Err(err) = self
+        let renderer = self.backend.renderer();
-            .backend
+        if let Err(err) = renderer.bind_wl_display(&niri.display_handle) {
-            .renderer()
-            .bind_wl_display(&niri.display_handle)
-        {
             warn!("error binding renderer wl_display: {err}");
         }
 
-        niri.add_output(self.output.clone(), None);
+        resources::init(renderer);
+        shaders::init(renderer);
+
+        niri.add_output(self.output.clone(), None, false);
     }
 
     pub fn seat_name(&self) -> String {
@@ -151,7 +153,12 @@ impl Winit {
         let _span = tracy_client::span!("Winit::render");
 
         // Render the elements.
-        let elements = niri.render::<GlesRenderer>(self.backend.renderer(), output, true);
+        let elements = niri.render::<GlesRenderer>(
+            self.backend.renderer(),
+            output,
+            true,
+            RenderTarget::Output,
+        );
 
         // Hand them over to winit.
         self.backend.bind().unwrap();
@@ -172,10 +179,12 @@ impl Winit {
                 .wait_for_frame_completion_before_queueing
             {
                 let _span = tracy_client::span!("wait for completion");
-                res.sync.wait();
+                if let Err(err) = res.sync.wait() {
+                    warn!("error waiting for frame completion: {err:?}");
+                }
             }
 
-            self.backend.submit(Some(&damage)).unwrap();
+            self.backend.submit(Some(damage)).unwrap();
 
             let mut presentation_feedbacks = niri.take_presentation_feedbacks(output, &res.states);
             let mode = output.current_mode().unwrap();
@@ -195,12 +204,16 @@ impl Winit {
         let output_state = niri.output_state.get_mut(output).unwrap();
         match mem::replace(&mut output_state.redraw_state, RedrawState::Idle) {
             RedrawState::Idle => unreachable!(),
-            RedrawState::Queued(_) => (),
+            RedrawState::Queued => (),
             RedrawState::WaitingForVBlank { .. } => unreachable!(),
             RedrawState::WaitingForEstimatedVBlank(_) => unreachable!(),
             RedrawState::WaitingForEstimatedVBlankAndQueued(_) => unreachable!(),
         }
 
+        output_state.frame_callback_sequence = output_state.frame_callback_sequence.wrapping_add(1);
+
+        // FIXME: this should wait until a frame callback from the host compositor, but it redraws
+        // right away instead.
         if output_state.unfinished_animations_remain {
             self.backend.window().request_redraw();
         }
@@ -213,21 +226,17 @@ impl Winit {
         renderer.set_debug_flags(renderer.debug_flags() ^ DebugFlags::TINT);
     }
 
-    pub fn import_dmabuf(&mut self, dmabuf: &Dmabuf) -> Result<(), ()> {
+    pub fn import_dmabuf(&mut self, dmabuf: &Dmabuf) -> bool {
         match self.backend.renderer().import_dmabuf(dmabuf, None) {
-            Ok(_texture) => Ok(()),
+            Ok(_texture) => true,
             Err(err) => {
                 debug!("error importing dmabuf: {err:?}");
-                Err(())
+                false
             }
         }
     }
 
-    pub fn ipc_outputs(&self) -> Rc<RefCell<HashMap<String, niri_ipc::Output>>> {
+    pub fn ipc_outputs(&self) -> Arc<Mutex<IpcOutputMap>> {
         self.ipc_outputs.clone()
     }
-
-    pub fn enabled_outputs(&self) -> Arc<Mutex<HashMap<String, Output>>> {
-        self.enabled_outputs.clone()
-    }
 }

src/cli.rs

@@ -0,0 +1,68 @@
+use std::ffi::OsString;
+use std::path::PathBuf;
+
+use clap::{Parser, Subcommand};
+use niri_ipc::Action;
+
+use crate::utils::version;
+
+#[derive(Parser)]
+#[command(author, version = version(), about, long_about = None)]
+#[command(args_conflicts_with_subcommands = true)]
+#[command(subcommand_value_name = "SUBCOMMAND")]
+#[command(subcommand_help_heading = "Subcommands")]
+pub struct Cli {
+    /// Path to config file (default: `$XDG_CONFIG_HOME/niri/config.kdl`).
+    #[arg(short, long)]
+    pub config: Option<PathBuf>,
+    /// Import environment globally to systemd and D-Bus, run D-Bus services.
+    ///
+    /// Set this flag in a systemd service started by your display manager, or when running
+    /// manually as your main compositor instance. Do not set when running as a nested window, or
+    /// on a TTY as your non-main compositor instance, to avoid messing up the global environment.
+    #[arg(long)]
+    pub session: bool,
+    /// Command to run upon compositor startup.
+    #[arg(last = true)]
+    pub command: Vec<OsString>,
+
+    #[command(subcommand)]
+    pub subcommand: Option<Sub>,
+}
+
+#[derive(Subcommand)]
+pub enum Sub {
+    /// Validate the config file.
+    Validate {
+        /// Path to config file (default: `$XDG_CONFIG_HOME/niri/config.kdl`).
+        #[arg(short, long)]
+        config: Option<PathBuf>,
+    },
+    /// Communicate with the running niri instance.
+    Msg {
+        #[command(subcommand)]
+        msg: Msg,
+        /// Format output as JSON.
+        #[arg(short, long)]
+        json: bool,
+    },
+    /// Cause a panic to check if the backtraces are good.
+    Panic,
+}
+
+#[derive(Subcommand)]
+pub enum Msg {
+    /// Print the version of the running niri instance.
+    Version,
+    /// List connected outputs.
+    Outputs,
+    /// Print information about the focused window.
+    FocusedWindow,
+    /// Perform an action.
+    Action {
+        #[command(subcommand)]
+        action: Action,
+    },
+    /// Request an error from the running niri instance.
+    RequestError,
+}

src/cursor.rs

@@ -8,8 +8,7 @@ use std::sync::Mutex;
 
 use anyhow::{anyhow, Context};
 use smithay::backend::allocator::Fourcc;
-use smithay::backend::renderer::element::texture::TextureBuffer;
+use smithay::backend::renderer::element::memory::MemoryRenderBuffer;
-use smithay::backend::renderer::gles::{GlesRenderer, GlesTexture};
 use smithay::input::pointer::{CursorIcon, CursorImageAttributes, CursorImageStatus};
 use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
 use smithay::utils::{IsAlive, Logical, Physical, Point, Transform};
@@ -224,7 +223,7 @@ pub enum RenderCursor {
     },
 }
 
-type TextureCache = HashMap<(CursorIcon, i32), Vec<Option<TextureBuffer<GlesTexture>>>>;
+type TextureCache = HashMap<(CursorIcon, i32), Vec<MemoryRenderBuffer>>;
 
 #[derive(Default)]
 pub struct CursorTextureCache {
@@ -238,12 +237,11 @@ impl CursorTextureCache {
 
     pub fn get(
         &self,
-        renderer: &mut GlesRenderer,
         icon: CursorIcon,
         scale: i32,
         cursor: &XCursor,
         idx: usize,
-    ) -> Option<TextureBuffer<GlesTexture>> {
+    ) -> MemoryRenderBuffer {
         self.cache
             .borrow_mut()
             .entry((icon, scale))
@@ -252,26 +250,14 @@ impl CursorTextureCache {
                     .frames()
                     .iter()
                     .map(|frame| {
-                        let _span = tracy_client::span!("create TextureBuffer");
+                        MemoryRenderBuffer::from_slice(
-
-                        let buffer = TextureBuffer::from_memory(
-                            renderer,
                             &frame.pixels_rgba,
-                            Fourcc::Abgr8888,
+                            Fourcc::Argb8888,
                             (frame.width as i32, frame.height as i32),
-                            false,
                             scale,
                             Transform::Normal,
                             None,
-                        );
+                        )
-
-                        match buffer {
-                            Ok(x) => Some(x),
-                            Err(err) => {
-                                warn!("error creating a cursor texture: {err:?}");
-                                None
-                            }
-                        }
                     })
                     .collect()
             })[idx]

src/dbus/freedesktop_screensaver.rs

@@ -0,0 +1,166 @@
+use std::collections::hash_map::Entry;
+use std::collections::HashMap;
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::{Arc, Mutex, OnceLock};
+
+use anyhow::Context;
+use futures_util::StreamExt;
+use zbus::fdo::{self, RequestNameFlags};
+use zbus::names::{OwnedUniqueName, UniqueName};
+use zbus::zvariant::NoneValue;
+use zbus::{dbus_interface, MessageHeader, Task};
+
+use super::Start;
+
+pub struct ScreenSaver {
+    is_inhibited: Arc<AtomicBool>,
+    is_broken: Arc<AtomicBool>,
+    inhibitors: Arc<Mutex<HashMap<u32, OwnedUniqueName>>>,
+    counter: u32,
+    monitor_task: Arc<OnceLock<Task<()>>>,
+}
+
+#[dbus_interface(name = "org.freedesktop.ScreenSaver")]
+impl ScreenSaver {
+    async fn inhibit(
+        &mut self,
+        #[zbus(header)] hdr: MessageHeader<'_>,
+        application_name: &str,
+        reason_for_inhibit: &str,
+    ) -> fdo::Result<u32> {
+        trace!(
+            "fdo inhibit, app: `{application_name}`, reason: `{reason_for_inhibit}`, owner: {:?}",
+            hdr.sender()
+        );
+
+        let Ok(Some(name)) = hdr.sender() else {
+            return Err(fdo::Error::Failed(String::from("no sender")));
+        };
+        let name = OwnedUniqueName::from(name.to_owned());
+
+        let mut inhibitors = self.inhibitors.lock().unwrap();
+
+        let mut cookie = None;
+        for _ in 0..3 {
+            // Start from 1 because some clients don't like 0.
+            self.counter = self.counter.wrapping_add(1);
+            if self.counter == 0 {
+                self.counter += 1;
+            }
+
+            if let Entry::Vacant(entry) = inhibitors.entry(self.counter) {
+                entry.insert(name);
+                self.is_inhibited.store(true, Ordering::SeqCst);
+                cookie = Some(self.counter);
+                break;
+            }
+        }
+
+        cookie.ok_or_else(|| fdo::Error::Failed(String::from("no available cookie")))
+    }
+
+    async fn un_inhibit(&mut self, cookie: u32) -> fdo::Result<()> {
+        trace!("fdo uninhibit, cookie: {cookie}");
+
+        let mut inhibitors = self.inhibitors.lock().unwrap();
+
+        if inhibitors.remove(&cookie).is_some() {
+            if inhibitors.is_empty() {
+                self.is_inhibited.store(false, Ordering::SeqCst);
+            }
+
+            Ok(())
+        } else {
+            Err(fdo::Error::Failed(String::from("invalid cookie")))
+        }
+    }
+}
+
+impl ScreenSaver {
+    pub fn new(is_inhibited: Arc<AtomicBool>) -> Self {
+        Self {
+            is_inhibited,
+            is_broken: Arc::new(AtomicBool::new(false)),
+            inhibitors: Arc::new(Mutex::new(HashMap::new())),
+            counter: 0,
+            monitor_task: Arc::new(OnceLock::new()),
+        }
+    }
+}
+
+async fn monitor_disappeared_clients(
+    conn: &zbus::Connection,
+    is_inhibited: Arc<AtomicBool>,
+    inhibitors: Arc<Mutex<HashMap<u32, OwnedUniqueName>>>,
+) -> anyhow::Result<()> {
+    let proxy = fdo::DBusProxy::new(conn)
+        .await
+        .context("error creating a DBusProxy")?;
+
+    let mut stream = proxy
+        .receive_name_owner_changed_with_args(&[(2, UniqueName::null_value())])
+        .await
+        .context("error creating a NameOwnerChanged stream")?;
+
+    while let Some(signal) = stream.next().await {
+        let args = signal
+            .args()
+            .context("error retrieving NameOwnerChanged args")?;
+
+        let Some(name) = &**args.old_owner() else {
+            continue;
+        };
+
+        if args.new_owner().is_none() {
+            trace!("fdo ScreenSaver client disappeared: {name}");
+
+            let mut inhibitors = inhibitors.lock().unwrap();
+            inhibitors.retain(|_, owner| owner != name);
+            is_inhibited.store(!inhibitors.is_empty(), Ordering::SeqCst);
+        } else {
+            error!("non-null new_owner should've been filtered out");
+        }
+    }
+
+    Ok(())
+}
+
+impl Start for ScreenSaver {
+    fn start(self) -> anyhow::Result<zbus::blocking::Connection> {
+        let is_inhibited = self.is_inhibited.clone();
+        let is_broken = self.is_broken.clone();
+        let inhibitors = self.inhibitors.clone();
+        let monitor_task = self.monitor_task.clone();
+
+        let conn = zbus::blocking::Connection::session()?;
+        let flags = RequestNameFlags::AllowReplacement
+            | RequestNameFlags::ReplaceExisting
+            | RequestNameFlags::DoNotQueue;
+
+        conn.object_server()
+            .at("/org/freedesktop/ScreenSaver", self)?;
+        conn.request_name_with_flags("org.freedesktop.ScreenSaver", flags)?;
+
+        let async_conn = conn.inner();
+        let future = {
+            let conn = async_conn.clone();
+            async move {
+                if let Err(err) =
+                    monitor_disappeared_clients(&conn, is_inhibited.clone(), inhibitors.clone())
+                        .await
+                {
+                    warn!("error monitoring org.freedesktop.ScreenSaver clients: {err:?}");
+                    is_broken.store(true, Ordering::SeqCst);
+                    is_inhibited.store(false, Ordering::SeqCst);
+                    inhibitors.lock().unwrap().clear();
+                }
+            }
+        };
+        let task = async_conn
+            .executor()
+            .spawn(future, "monitor disappearing clients");
+        monitor_task.set(task).unwrap();
+
+        Ok(conn)
+    }
+}

src/dbus/gnome_shell_screenshot.rs

@@ -1,6 +1,5 @@
 use std::path::PathBuf;
 
-use smithay::reexports::calloop;
 use zbus::dbus_interface;
 use zbus::fdo::{self, RequestNameFlags};
 

src/dbus/mod.rs

@@ -1,9 +1,9 @@
-use smithay::reexports::calloop;
 use zbus::blocking::Connection;
 use zbus::Interface;
 
 use crate::niri::State;
 
+pub mod freedesktop_screensaver;
 pub mod gnome_shell_screenshot;
 pub mod mutter_display_config;
 pub mod mutter_service_channel;
@@ -13,6 +13,7 @@ pub mod mutter_screen_cast;
 #[cfg(feature = "xdp-gnome-screencast")]
 use mutter_screen_cast::ScreenCast;
 
+use self::freedesktop_screensaver::ScreenSaver;
 use self::mutter_display_config::DisplayConfig;
 use self::mutter_service_channel::ServiceChannel;
 
@@ -24,6 +25,7 @@ trait Start: Interface {
 pub struct DBusServers {
     pub conn_service_channel: Option<Connection>,
     pub conn_display_config: Option<Connection>,
+    pub conn_screen_saver: Option<Connection>,
     pub conn_screen_shot: Option<Connection>,
     #[cfg(feature = "xdp-gnome-screencast")]
     pub conn_screen_cast: Option<Connection>,
@@ -45,9 +47,12 @@ impl DBusServers {
         }
 
         if is_session_instance || config.debug.dbus_interfaces_in_non_session_instances {
-            let display_config = DisplayConfig::new(backend.enabled_outputs());
+            let display_config = DisplayConfig::new(backend.ipc_outputs());
             dbus.conn_display_config = try_start(display_config);
 
+            let screen_saver = ScreenSaver::new(niri.is_fdo_idle_inhibited.clone());
+            dbus.conn_screen_saver = try_start(screen_saver);
+
             let (to_niri, from_screenshot) = calloop::channel::channel();
             let (to_screenshot, from_niri) = async_channel::unbounded();
             niri.event_loop
@@ -62,7 +67,7 @@ impl DBusServers {
             dbus.conn_screen_shot = try_start(screenshot);
 
             #[cfg(feature = "xdp-gnome-screencast")]
-            {
+            if niri.pipewire.is_some() {
                 let (to_niri, from_screen_cast) = calloop::channel::channel();
                 niri.event_loop
                     .insert_source(from_screen_cast, {
@@ -75,8 +80,10 @@ impl DBusServers {
                         }
                     })
                     .unwrap();
-                let screen_cast = ScreenCast::new(backend.enabled_outputs(), to_niri);
+                let screen_cast = ScreenCast::new(backend.ipc_outputs(), to_niri);
                 dbus.conn_screen_cast = try_start(screen_cast);
+            } else {
+                warn!("disabling screencast support because we couldn't start PipeWire");
             }
         }
 

src/dbus/mutter_display_config.rs

@@ -2,15 +2,15 @@ use std::collections::HashMap;
 use std::sync::{Arc, Mutex};
 
 use serde::Serialize;
-use smithay::output::Output;
 use zbus::fdo::RequestNameFlags;
 use zbus::zvariant::{self, OwnedValue, Type};
-use zbus::{dbus_interface, fdo};
+use zbus::{dbus_interface, fdo, SignalContext};
 
 use super::Start;
+use crate::backend::IpcOutputMap;
 
 pub struct DisplayConfig {
-    enabled_outputs: Arc<Mutex<HashMap<String, Output>>>,
+    ipc_outputs: Arc<Mutex<IpcOutputMap>>,
 }
 
 #[derive(Serialize, Type)]
@@ -53,12 +53,14 @@ impl DisplayConfig {
         HashMap<String, OwnedValue>,
     )> {
         // Construct the DBus response.
-        let mut monitors: Vec<Monitor> = self
+        let mut monitors: Vec<(Monitor, LogicalMonitor)> = self
-            .enabled_outputs
+            .ipc_outputs
             .lock()
             .unwrap()
-            .keys()
+            .iter()
-            .map(|c| {
+            // Take only enabled outputs.
+            .filter(|(_, output)| output.current_mode.is_some() && output.logical.is_some())
+            .map(|(c, output)| {
                 // Loosely matches the check in Mutter.
                 let is_laptop_panel = matches!(c.get(..4), Some("eDP-" | "LVDS" | "DSI-"));
 
@@ -78,46 +80,91 @@ impl DisplayConfig {
                     OwnedValue::from(is_laptop_panel),
                 );
 
-                Monitor {
+                let mut modes: Vec<Mode> = output
+                    .modes
+                    .iter()
+                    .map(|m| {
+                        let niri_ipc::Mode {
+                            width,
+                            height,
+                            refresh_rate,
+                            is_preferred,
+                        } = *m;
+                        let refresh = refresh_rate as f64 / 1000.;
+
+                        Mode {
+                            id: format!("{width}x{height}@{refresh:.3}"),
+                            width: i32::from(width),
+                            height: i32::from(height),
+                            refresh_rate: refresh,
+                            preferred_scale: 1.,
+                            supported_scales: vec![1., 2., 3.],
+                            properties: HashMap::from([(
+                                String::from("is-preferred"),
+                                OwnedValue::from(is_preferred),
+                            )]),
+                        }
+                    })
+                    .collect();
+                modes[output.current_mode.unwrap()]
+                    .properties
+                    .insert(String::from("is-current"), OwnedValue::from(true));
+
+                let monitor = Monitor {
                     names: (c.clone(), String::new(), String::new(), serial),
-                    modes: vec![],
+                    modes,
                     properties,
-                }
+                };
+
+                let logical = output.logical.as_ref().unwrap();
+
+                let transform = match logical.transform {
+                    niri_ipc::Transform::Normal => 0,
+                    niri_ipc::Transform::_90 => 1,
+                    niri_ipc::Transform::_180 => 2,
+                    niri_ipc::Transform::_270 => 3,
+                    niri_ipc::Transform::Flipped => 4,
+                    niri_ipc::Transform::Flipped90 => 5,
+                    niri_ipc::Transform::Flipped180 => 6,
+                    niri_ipc::Transform::Flipped270 => 7,
+                };
+
+                let logical_monitor = LogicalMonitor {
+                    x: logical.x,
+                    y: logical.y,
+                    scale: logical.scale,
+                    transform,
+                    is_primary: false,
+                    monitors: vec![monitor.names.clone()],
+                    properties: HashMap::new(),
+                };
+
+                (monitor, logical_monitor)
             })
             .collect();
 
         // Sort the built-in monitor first, then by connector name.
         monitors.sort_unstable_by(|a, b| {
-            let a_is_builtin = a.properties.contains_key("display-name");
+            let a_is_builtin = a.0.properties.contains_key("display-name");
-            let b_is_builtin = b.properties.contains_key("display-name");
+            let b_is_builtin = b.0.properties.contains_key("display-name");
             a_is_builtin
                 .cmp(&b_is_builtin)
                 .reverse()
-                .then_with(|| a.names.0.cmp(&b.names.0))
+                .then_with(|| a.0.names.0.cmp(&b.0.names.0))
         });
 
-        let logical_monitors = monitors
+        let (monitors, logical_monitors) = monitors.into_iter().unzip();
-            .iter()
+        let properties = HashMap::from([(String::from("layout-mode"), OwnedValue::from(1u32))]);
-            .map(|m| LogicalMonitor {
+        Ok((0, monitors, logical_monitors, properties))
-                x: 0,
-                y: 0,
-                scale: 1.,
-                transform: 0,
-                is_primary: false,
-                monitors: vec![m.names.clone()],
-                properties: HashMap::new(),
-            })
-            .collect();
-
-        Ok((0, monitors, logical_monitors, HashMap::new()))
     }
 
-    // FIXME: monitors-changed signal.
+    #[dbus_interface(signal)]
+    pub async fn monitors_changed(ctxt: &SignalContext<'_>) -> zbus::Result<()>;
 }
 
 impl DisplayConfig {
-    pub fn new(enabled_outputs: Arc<Mutex<HashMap<String, Output>>>) -> Self {
+    pub fn new(ipc_outputs: Arc<Mutex<IpcOutputMap>>) -> Self {
-        Self { enabled_outputs }
+        Self { ipc_outputs }
     }
 }
 

src/dbus/mutter_screen_cast.rs

@@ -5,16 +5,16 @@ use std::sync::{Arc, Mutex};
 
 use serde::Deserialize;
 use smithay::output::Output;
-use smithay::reexports::calloop;
 use zbus::fdo::RequestNameFlags;
-use zbus::zvariant::{DeserializeDict, OwnedObjectPath, Type, Value};
+use zbus::zvariant::{DeserializeDict, OwnedObjectPath, SerializeDict, Type, Value};
 use zbus::{dbus_interface, fdo, InterfaceRef, ObjectServer, SignalContext};
 
 use super::Start;
+use crate::backend::IpcOutputMap;
 
 #[derive(Clone)]
 pub struct ScreenCast {
-    enabled_outputs: Arc<Mutex<HashMap<String, Output>>>,
+    ipc_outputs: Arc<Mutex<IpcOutputMap>>,
     to_niri: calloop::channel::Sender<ScreenCastToNiri>,
     #[allow(clippy::type_complexity)]
     sessions: Arc<Mutex<Vec<(Session, InterfaceRef<Session>)>>>,
@@ -23,10 +23,11 @@ pub struct ScreenCast {
 #[derive(Clone)]
 pub struct Session {
     id: usize,
-    enabled_outputs: Arc<Mutex<HashMap<String, Output>>>,
+    ipc_outputs: Arc<Mutex<IpcOutputMap>>,
     to_niri: calloop::channel::Sender<ScreenCastToNiri>,
     #[allow(clippy::type_complexity)]
     streams: Arc<Mutex<Vec<(Stream, InterfaceRef<Stream>)>>>,
+    stopped: Arc<AtomicBool>,
 }
 
 #[derive(Debug, Default, Deserialize, Type, Clone, Copy)]
@@ -48,16 +49,26 @@ struct RecordMonitorProperties {
 
 #[derive(Clone)]
 pub struct Stream {
-    output: Output,
+    // FIXME: update on scale changes and whatnot.
+    output: niri_ipc::Output,
     cursor_mode: CursorMode,
     was_started: Arc<AtomicBool>,
     to_niri: calloop::channel::Sender<ScreenCastToNiri>,
 }
 
+#[derive(Debug, SerializeDict, Type, Value)]
+#[zvariant(signature = "dict")]
+struct StreamParameters {
+    /// Position of the stream in logical coordinates.
+    position: (i32, i32),
+    /// Size of the stream in logical coordinates.
+    size: (i32, i32),
+}
+
 pub enum ScreenCastToNiri {
     StartCast {
         session_id: usize,
-        output: Output,
+        output: String,
         cursor_mode: CursorMode,
         signal_ctx: SignalContext<'static>,
     },
@@ -85,11 +96,7 @@ impl ScreenCast {
         let path = format!("/org/gnome/Mutter/ScreenCast/Session/u{}", session_id);
         let path = OwnedObjectPath::try_from(path).unwrap();
 
-        let session = Session::new(
+        let session = Session::new(session_id, self.ipc_outputs.clone(), self.to_niri.clone());
-            session_id,
-            self.enabled_outputs.clone(),
-            self.to_niri.clone(),
-        );
         match server.at(&path, session.clone()).await {
             Ok(true) => {
                 let iface = server.interface(&path).await.unwrap();
@@ -129,6 +136,11 @@ impl Session {
     ) {
         debug!("stop");
 
+        if self.stopped.swap(true, Ordering::SeqCst) {
+            // Already stopped.
+            return;
+        }
+
         Session::closed(&ctxt).await.unwrap();
 
         if let Err(err) = self.to_niri.send(ScreenCastToNiri::StopCast {
@@ -156,10 +168,14 @@ impl Session {
     ) -> fdo::Result<OwnedObjectPath> {
         debug!(connector, ?properties, "record_monitor");
 
-        let Some(output) = self.enabled_outputs.lock().unwrap().get(connector).cloned() else {
+        let Some(output) = self.ipc_outputs.lock().unwrap().get(connector).cloned() else {
             return Err(fdo::Error::Failed("no such monitor".to_owned()));
         };
 
+        if output.logical.is_none() {
+            return Err(fdo::Error::Failed("monitor is disabled".to_owned()));
+        }
+
         static NUMBER: AtomicUsize = AtomicUsize::new(0);
         let path = format!(
             "/org/gnome/Mutter/ScreenCast/Stream/u{}",
@@ -169,7 +185,7 @@ impl Session {
 
         let cursor_mode = properties.cursor_mode.unwrap_or_default();
 
-        let stream = Stream::new(output, cursor_mode, self.to_niri.clone());
+        let stream = Stream::new(output.clone(), cursor_mode, self.to_niri.clone());
         match server.at(&path, stream.clone()).await {
             Ok(true) => {
                 let iface = server.interface(&path).await.unwrap();
@@ -195,15 +211,24 @@ impl Stream {
     #[dbus_interface(signal)]
     pub async fn pipe_wire_stream_added(ctxt: &SignalContext<'_>, node_id: u32)
         -> zbus::Result<()>;
+
+    #[dbus_interface(property)]
+    async fn parameters(&self) -> StreamParameters {
+        let logical = self.output.logical.as_ref().unwrap();
+        StreamParameters {
+            position: (logical.x, logical.y),
+            size: (logical.width as i32, logical.height as i32),
+        }
+    }
 }
 
 impl ScreenCast {
     pub fn new(
-        enabled_outputs: Arc<Mutex<HashMap<String, Output>>>,
+        ipc_outputs: Arc<Mutex<IpcOutputMap>>,
         to_niri: calloop::channel::Sender<ScreenCastToNiri>,
     ) -> Self {
         Self {
-            enabled_outputs,
+            ipc_outputs,
             to_niri,
             sessions: Arc::new(Mutex::new(vec![])),
         }
@@ -228,14 +253,15 @@ impl Start for ScreenCast {
 impl Session {
     pub fn new(
         id: usize,
-        enabled_outputs: Arc<Mutex<HashMap<String, Output>>>,
+        ipc_outputs: Arc<Mutex<IpcOutputMap>>,
         to_niri: calloop::channel::Sender<ScreenCastToNiri>,
     ) -> Self {
         Self {
             id,
-            enabled_outputs,
+            ipc_outputs,
             streams: Arc::new(Mutex::new(vec![])),
             to_niri,
+            stopped: Arc::new(AtomicBool::new(false)),
         }
     }
 }
@@ -250,7 +276,7 @@ impl Drop for Session {
 
 impl Stream {
     pub fn new(
-        output: Output,
+        output: niri_ipc::Output,
         cursor_mode: CursorMode,
         to_niri: calloop::channel::Sender<ScreenCastToNiri>,
     ) -> Self {
@@ -269,7 +295,7 @@ impl Stream {
 
         let msg = ScreenCastToNiri::StartCast {
             session_id,
-            output: self.output.clone(),
+            output: self.output.name.clone(),
             cursor_mode: self.cursor_mode,
             signal_ctx: ctxt,
         };

src/frame_clock.rs

@@ -7,10 +7,11 @@ use crate::utils::get_monotonic_time;
 pub struct FrameClock {
     last_presentation_time: Option<Duration>,
     refresh_interval_ns: Option<NonZeroU64>,
+    vrr: bool,
 }
 
 impl FrameClock {
-    pub fn new(refresh_interval: Option<Duration>) -> Self {
+    pub fn new(refresh_interval: Option<Duration>, vrr: bool) -> Self {
         let refresh_interval_ns = if let Some(interval) = &refresh_interval {
             assert_eq!(interval.as_secs(), 0);
             Some(NonZeroU64::new(interval.subsec_nanos().into()).unwrap())
@@ -21,6 +22,7 @@ impl FrameClock {
         Self {
             last_presentation_time: None,
             refresh_interval_ns,
+            vrr,
         }
     }
 
@@ -29,6 +31,15 @@ impl FrameClock {
             .map(|r| Duration::from_nanos(r.get()))
     }
 
+    pub fn set_vrr(&mut self, vrr: bool) {
+        if self.vrr == vrr {
+            return;
+        }
+
+        self.vrr = vrr;
+        self.last_presentation_time = None;
+    }
+
     pub fn presented(&mut self, presentation_time: Duration) {
         if presentation_time.is_zero() {
             // Not interested in these.
@@ -71,6 +82,13 @@ impl FrameClock {
         let since_last_ns =
             since_last.as_secs() * 1_000_000_000 + u64::from(since_last.subsec_nanos());
         let to_next_ns = (since_last_ns / refresh_interval_ns + 1) * refresh_interval_ns;
-        last_presentation_time + Duration::from_nanos(to_next_ns)
+
+        // If VRR is enabled and more than one frame passed since last presentation, assume that we
+        // can present immediately.
+        if self.vrr && to_next_ns > refresh_interval_ns {
+            now
+        } else {
+            last_presentation_time + Duration::from_nanos(to_next_ns)
+        }
     }
 }

src/handlers/compositor.rs

@@ -16,9 +16,9 @@ use smithay::wayland::dmabuf::get_dmabuf;
 use smithay::wayland::shm::{ShmHandler, ShmState};
 use smithay::{delegate_compositor, delegate_shm};
 
-use super::xdg_shell;
+use super::xdg_shell::add_mapped_toplevel_pre_commit_hook;
 use crate::niri::{ClientState, State};
-use crate::utils::clone2;
+use crate::window::{InitialConfigureState, Mapped, ResolvedWindowRules, Unmapped};
 
 impl CompositorHandler for State {
     fn compositor_state(&mut self) -> &mut CompositorState {
@@ -75,7 +75,7 @@ impl CompositorHandler for State {
                     }
                 }
             }
-        })
+        });
     }
 
     fn commit(&mut self, surface: &WlSurface) {
@@ -93,45 +93,145 @@ impl CompositorHandler for State {
             root_surface = parent;
         }
 
+        // Update the cached root surface.
+        self.niri
+            .root_surface
+            .insert(surface.clone(), root_surface.clone());
+
         if surface == &root_surface {
             // This is a root surface commit. It might have mapped a previously-unmapped toplevel.
             if let Entry::Occupied(entry) = self.niri.unmapped_windows.entry(surface.clone()) {
                 let is_mapped =
-                    with_renderer_surface_state(surface, |state| state.buffer().is_some());
+                    with_renderer_surface_state(surface, |state| state.buffer().is_some())
+                        .unwrap_or_else(|| {
+                            error!("no renderer surface state even though we use commit handler");
+                            false
+                        });
 
                 if is_mapped {
                     // The toplevel got mapped.
-                    let window = entry.remove();
+                    let Unmapped { window, state } = entry.remove();
+
                     window.on_commit();
 
-                    if let Some(output) = self.niri.layout.add_window(window, None, false).cloned()
+                    let toplevel = window.toplevel().expect("no X11 support");
-                    {
+
-                        self.niri.queue_redraw(output);
+                    let (rules, width, is_full_width, output) =
+                        if let InitialConfigureState::Configured {
+                            rules,
+                            width,
+                            is_full_width,
+                            output,
+                        } = state
+                        {
+                            // Check that the output is still connected.
+                            let output =
+                                output.filter(|o| self.niri.layout.monitor_for_output(o).is_some());
+
+                            (rules, width, is_full_width, output)
+                        } else {
+                            error!("window map must happen after initial configure");
+                            (ResolvedWindowRules::empty(), None, false, None)
+                        };
+
+                    let parent = toplevel
+                        .parent()
+                        .and_then(|parent| self.niri.layout.find_window_and_output(&parent))
+                        // Only consider the parent if we configured the window for the same
+                        // output.
+                        //
+                        // Normally when we're following the parent, the configured output will be
+                        // None. If the configured output is set, that means it was set explicitly
+                        // by a window rule or a fullscreen request.
+                        .filter(|(_, parent_output)| {
+                            output.is_none() || output.as_ref() == Some(*parent_output)
+                        })
+                        .map(|(mapped, _)| mapped.window.clone());
+
+                    let hook = add_mapped_toplevel_pre_commit_hook(toplevel);
+                    let mapped = Mapped::new(window, rules, hook);
+                    let window = mapped.window.clone();
+
+                    let output = if let Some(p) = parent {
+                        // Open dialogs immediately to the right of their parent window.
+                        self.niri
+                            .layout
+                            .add_window_right_of(&p, mapped, width, is_full_width)
+                    } else if let Some(output) = &output {
+                        self.niri
+                            .layout
+                            .add_window_on_output(output, mapped, width, is_full_width);
+                        Some(output)
+                    } else {
+                        self.niri.layout.add_window(mapped, width, is_full_width)
+                    };
+
+                    if let Some(output) = output.cloned() {
+                        self.niri.layout.start_open_animation_for_window(&window);
+
+                        let new_active_window =
+                            self.niri.layout.active_window().map(|(m, _)| &m.window);
+                        if new_active_window == Some(&window) {
+                            self.maybe_warp_cursor_to_focus();
+                        }
+
+                        self.niri.queue_redraw(&output);
                     }
                     return;
                 }
 
                 // The toplevel remains unmapped.
-                let window = entry.get();
+                let unmapped = entry.get();
-                xdg_shell::send_initial_configure_if_needed(window.toplevel());
+                if unmapped.needs_initial_configure() {
+                    let toplevel = unmapped.window.toplevel().expect("no x11 support").clone();
+                    self.queue_initial_configure(toplevel);
+                }
                 return;
             }
 
             // This is a commit of a previously-mapped root or a non-toplevel root.
-            if let Some(win_out) = self.niri.layout.find_window_and_output(surface) {
+            if let Some((mapped, output)) = self.niri.layout.find_window_and_output(surface) {
-                let (window, output) = clone2(win_out);
+                let window = mapped.window.clone();
-
+                let output = output.clone();
-                window.on_commit();
 
                 // This is a commit of a previously-mapped toplevel.
                 let is_mapped =
-                    with_renderer_surface_state(surface, |state| state.buffer().is_some());
+                    with_renderer_surface_state(surface, |state| state.buffer().is_some())
+                        .unwrap_or_else(|| {
+                            error!("no renderer surface state even though we use commit handler");
+                            false
+                        });
+
+                // Must start the close animation before window.on_commit().
+                if !is_mapped {
+                    self.backend.with_primary_renderer(|renderer| {
+                        self.niri
+                            .layout
+                            .start_close_animation_for_window(renderer, &window);
+                    });
+                }
+
+                window.on_commit();
 
                 if !is_mapped {
                     // The toplevel got unmapped.
+                    //
+                    // Test client: wleird-unmap.
+                    let active_window = self.niri.layout.active_window().map(|(m, _)| &m.window);
+                    let was_active = active_window == Some(&window);
+
                     self.niri.layout.remove_window(&window);
-                    self.niri.unmapped_windows.insert(surface.clone(), window);
+
-                    self.niri.queue_redraw(output);
+                    if was_active {
+                        self.maybe_warp_cursor_to_focus();
+                    }
+
+                    // Newly-unmapped toplevels must perform the initial commit-configure sequence
+                    // afresh.
+                    let unmapped = Unmapped::new(window);
+                    self.niri.unmapped_windows.insert(surface.clone(), unmapped);
+
+                    self.niri.queue_redraw(&output);
                     return;
                 }
 
@@ -141,7 +241,7 @@ impl CompositorHandler for State {
                 // Popup placement depends on window size which might have changed.
                 self.update_reactive_popups(&window, &output);
 
-                self.niri.queue_redraw(output);
+                self.niri.queue_redraw(&output);
                 return;
             }
 
@@ -150,10 +250,12 @@ impl CompositorHandler for State {
 
         // This is a commit of a non-root or a non-toplevel root.
         let root_window_output = self.niri.layout.find_window_and_output(&root_surface);
-        if let Some((window, output)) = root_window_output.map(clone2) {
+        if let Some((mapped, output)) = root_window_output {
+            let window = mapped.window.clone();
+            let output = output.clone();
             window.on_commit();
             self.niri.layout.update_window(&window);
-            self.niri.queue_redraw(output);
+            self.niri.queue_redraw(&output);
             return;
         }
 
@@ -161,7 +263,7 @@ impl CompositorHandler for State {
         self.popups_handle_commit(surface);
         if let Some(popup) = self.niri.popups.find_popup(surface) {
             if let Some(output) = self.output_for_popup(&popup) {
-                self.niri.queue_redraw(output.clone());
+                self.niri.queue_redraw(&output.clone());
             }
         }
 
@@ -186,13 +288,31 @@ impl CompositorHandler for State {
             for (output, state) in &self.niri.output_state {
                 if let Some(lock_surface) = &state.lock_surface {
                     if lock_surface.wl_surface() == surface {
-                        self.niri.queue_redraw(output.clone());
+                        self.niri.queue_redraw(&output.clone());
                         break;
                     }
                 }
             }
         }
     }
+
+    fn destroyed(&mut self, surface: &WlSurface) {
+        // Clients may destroy their subsurfaces before the main surface. Ensure we have a snapshot
+        // when that happens, so that the closing animation includes all these subsurfaces.
+        //
+        // Test client: alacritty with CSD.
+        if let Some(root) = self.niri.root_surface.get(surface) {
+            if let Some((mapped, _)) = self.niri.layout.find_window_and_output(root) {
+                self.backend.with_primary_renderer(|renderer| {
+                    mapped.store_unmap_snapshot_if_empty(renderer);
+                });
+            }
+        }
+
+        self.niri
+            .root_surface
+            .retain(|k, v| k != surface && v != surface);
+    }
 }
 
 impl BufferHandler for State {

src/handlers/layer_shell.rs

@@ -50,7 +50,7 @@ impl WlrLayerShellHandler for State {
             None
         };
         if let Some(output) = output {
-            self.niri.output_resized(output);
+            self.niri.output_resized(&output);
         }
     }
 
@@ -107,6 +107,6 @@ impl State {
         }
         drop(map);
 
-        self.niri.output_resized(output);
+        self.niri.output_resized(&output);
     }
 }

src/handlers/mod.rs

@@ -9,10 +9,13 @@ use std::sync::Arc;
 use std::thread;
 
 use smithay::backend::allocator::dmabuf::Dmabuf;
+use smithay::backend::drm::DrmNode;
+use smithay::backend::input::TabletToolDescriptor;
 use smithay::desktop::{PopupKind, PopupManager};
 use smithay::input::pointer::{CursorIcon, CursorImageStatus, PointerHandle};
-use smithay::input::{Seat, SeatHandler, SeatState};
+use smithay::input::{keyboard, Seat, SeatHandler, SeatState};
 use smithay::output::Output;
+use smithay::reexports::wayland_protocols::xdg::shell::server::xdg_toplevel;
 use smithay::reexports::wayland_server::protocol::wl_data_source::WlDataSource;
 use smithay::reexports::wayland_server::protocol::wl_output::WlOutput;
 use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
@@ -20,7 +23,13 @@ use smithay::reexports::wayland_server::Resource;
 use smithay::utils::{Logical, Rectangle, Size};
 use smithay::wayland::compositor::{send_surface_state, with_states};
 use smithay::wayland::dmabuf::{DmabufGlobal, DmabufHandler, DmabufState, ImportNotifier};
+use smithay::wayland::drm_lease::{
+    DrmLease, DrmLeaseBuilder, DrmLeaseHandler, DrmLeaseRequest, DrmLeaseState, LeaseRejected,
+};
+use smithay::wayland::idle_inhibit::IdleInhibitHandler;
+use smithay::wayland::idle_notify::{IdleNotifierHandler, IdleNotifierState};
 use smithay::wayland::input_method::{InputMethodHandler, PopupSurface};
+use smithay::wayland::output::OutputHandler;
 use smithay::wayland::pointer_constraints::PointerConstraintsHandler;
 use smithay::wayland::security_context::{
     SecurityContext, SecurityContextHandler, SecurityContextListenerSource,
@@ -37,20 +46,29 @@ use smithay::wayland::selection::{SelectionHandler, SelectionTarget};
 use smithay::wayland::session_lock::{
     LockSurface, SessionLockHandler, SessionLockManagerState, SessionLocker,
 };
+use smithay::wayland::tablet_manager::TabletSeatHandler;
 use smithay::{
     delegate_cursor_shape, delegate_data_control, delegate_data_device, delegate_dmabuf,
-    delegate_input_method_manager, delegate_output, delegate_pointer_constraints,
+    delegate_drm_lease, delegate_idle_inhibit, delegate_idle_notify, delegate_input_method_manager,
-    delegate_pointer_gestures, delegate_presentation, delegate_primary_selection,
+    delegate_output, delegate_pointer_constraints, delegate_pointer_gestures,
-    delegate_relative_pointer, delegate_seat, delegate_security_context, delegate_session_lock,
+    delegate_presentation, delegate_primary_selection, delegate_relative_pointer, delegate_seat,
-    delegate_tablet_manager, delegate_text_input_manager, delegate_virtual_keyboard_manager,
+    delegate_security_context, delegate_session_lock, delegate_tablet_manager,
+    delegate_text_input_manager, delegate_viewporter, delegate_virtual_keyboard_manager,
 };
 
 use crate::niri::{ClientState, State};
+use crate::protocols::foreign_toplevel::{
+    self, ForeignToplevelHandler, ForeignToplevelManagerState,
+};
+use crate::protocols::gamma_control::{GammaControlHandler, GammaControlManagerState};
+use crate::protocols::screencopy::{Screencopy, ScreencopyHandler};
 use crate::utils::output_size;
+use crate::{delegate_foreign_toplevel, delegate_gamma_control, delegate_screencopy};
 
 impl SeatHandler for State {
     type KeyboardFocus = WlSurface;
     type PointerFocus = WlSurface;
+    type TouchFocus = WlSurface;
 
     fn seat_state(&mut self) -> &mut SeatState<State> {
         &mut self.niri.seat_state
@@ -73,14 +91,36 @@ impl SeatHandler for State {
         set_data_device_focus(dh, seat, client.clone());
         set_primary_focus(dh, seat, client);
     }
+
+    fn led_state_changed(&mut self, _seat: &Seat<Self>, led_state: keyboard::LedState) {
+        let keyboards = self
+            .niri
+            .devices
+            .iter()
+            .filter(|device| device.has_capability(input::DeviceCapability::Keyboard))
+            .cloned();
+
+        for mut keyboard in keyboards {
+            keyboard.led_update(led_state.into());
+        }
+    }
 }
 delegate_seat!(State);
 delegate_cursor_shape!(State);
-delegate_tablet_manager!(State);
 delegate_pointer_gestures!(State);
 delegate_relative_pointer!(State);
 delegate_text_input_manager!(State);
 
+impl TabletSeatHandler for State {
+    fn tablet_tool_image(&mut self, _tool: &TabletToolDescriptor, image: CursorImageStatus) {
+        // FIXME: tablet tools should have their own cursors.
+        self.niri.cursor_manager.set_cursor_image(image);
+        // FIXME: granular.
+        self.niri.queue_redraw_all();
+    }
+}
+delegate_tablet_manager!(State);
+
 impl PointerConstraintsHandler for State {
     fn new_constraint(&mut self, _surface: &WlSurface, pointer: &PointerHandle<Self>) {
         self.niri.maybe_activate_pointer_constraint(
@@ -115,7 +155,7 @@ impl InputMethodHandler for State {
         self.niri
             .layout
             .find_window_and_output(parent)
-            .map(|(window, _)| window.geometry())
+            .map(|(mapped, _)| mapped.window.geometry())
             .unwrap_or_default()
     }
 }
@@ -189,6 +229,11 @@ impl DataControlHandler for State {
 
 delegate_data_control!(State);
 
+impl OutputHandler for State {
+    fn output_bound(&mut self, output: Output, wl_output: WlOutput) {
+        foreign_toplevel::on_output_bound(self, &output, &wl_output);
+    }
+}
 delegate_output!(State);
 
 delegate_presentation!(State);
@@ -204,13 +249,10 @@ impl DmabufHandler for State {
         dmabuf: Dmabuf,
         notifier: ImportNotifier,
     ) {
-        match self.backend.import_dmabuf(&dmabuf) {
+        if self.backend.import_dmabuf(&dmabuf) {
-            Ok(_) => {
+            let _ = notifier.successful::<State>();
-                let _ = notifier.successful::<State>();
+        } else {
-            }
+            notifier.failed();
-            Err(_) => {
-                notifier.failed();
-            }
         }
     }
 }
@@ -268,7 +310,7 @@ impl SecurityContextHandler for State {
                 });
 
                 if let Err(err) = state.niri.display_handle.insert_client(client, data) {
-                    error!("error inserting client: {err}");
+                    warn!("error inserting client: {err}");
                 } else {
                     trace!("inserted a new restricted client, context={context:?}");
                 }
@@ -277,3 +319,167 @@ impl SecurityContextHandler for State {
     }
 }
 delegate_security_context!(State);
+
+impl IdleNotifierHandler for State {
+    fn idle_notifier_state(&mut self) -> &mut IdleNotifierState<Self> {
+        &mut self.niri.idle_notifier_state
+    }
+}
+delegate_idle_notify!(State);
+
+impl IdleInhibitHandler for State {
+    fn inhibit(&mut self, surface: WlSurface) {
+        self.niri.idle_inhibiting_surfaces.insert(surface);
+    }
+
+    fn uninhibit(&mut self, surface: WlSurface) {
+        self.niri.idle_inhibiting_surfaces.remove(&surface);
+    }
+}
+delegate_idle_inhibit!(State);
+
+impl ForeignToplevelHandler for State {
+    fn foreign_toplevel_manager_state(&mut self) -> &mut ForeignToplevelManagerState {
+        &mut self.niri.foreign_toplevel_state
+    }
+
+    fn activate(&mut self, wl_surface: WlSurface) {
+        if let Some((mapped, _)) = self.niri.layout.find_window_and_output(&wl_surface) {
+            let window = mapped.window.clone();
+            self.niri.layout.activate_window(&window);
+            self.niri.queue_redraw_all();
+        }
+    }
+
+    fn close(&mut self, wl_surface: WlSurface) {
+        if let Some((mapped, _)) = self.niri.layout.find_window_and_output(&wl_surface) {
+            mapped.toplevel().send_close();
+        }
+    }
+
+    fn set_fullscreen(&mut self, wl_surface: WlSurface, wl_output: Option<WlOutput>) {
+        if let Some((mapped, current_output)) = self.niri.layout.find_window_and_output(&wl_surface)
+        {
+            if !mapped
+                .toplevel()
+                .current_state()
+                .capabilities
+                .contains(xdg_toplevel::WmCapabilities::Fullscreen)
+            {
+                return;
+            }
+
+            let window = mapped.window.clone();
+
+            if let Some(requested_output) = wl_output.as_ref().and_then(Output::from_resource) {
+                if &requested_output != current_output {
+                    self.niri
+                        .layout
+                        .move_window_to_output(&window, &requested_output);
+                }
+            }
+
+            self.niri.layout.set_fullscreen(&window, true);
+        }
+    }
+
+    fn unset_fullscreen(&mut self, wl_surface: WlSurface) {
+        if let Some((mapped, _)) = self.niri.layout.find_window_and_output(&wl_surface) {
+            let window = mapped.window.clone();
+            self.niri.layout.set_fullscreen(&window, false);
+        }
+    }
+}
+delegate_foreign_toplevel!(State);
+
+impl ScreencopyHandler for State {
+    fn frame(&mut self, screencopy: Screencopy) {
+        if let Err(err) = self
+            .niri
+            .render_for_screencopy(&mut self.backend, screencopy)
+        {
+            warn!("error rendering for screencopy: {err:?}");
+        }
+    }
+}
+delegate_screencopy!(State);
+
+impl DrmLeaseHandler for State {
+    fn drm_lease_state(&mut self, node: DrmNode) -> &mut DrmLeaseState {
+        self.backend
+            .tty()
+            .get_device_from_node(node)
+            .unwrap()
+            .drm_lease_state
+            .as_mut()
+            .unwrap()
+    }
+
+    fn lease_request(
+        &mut self,
+        node: DrmNode,
+        request: DrmLeaseRequest,
+    ) -> Result<DrmLeaseBuilder, LeaseRejected> {
+        debug!(
+            "Received lease request for {} connectors",
+            request.connectors.len()
+        );
+        self.backend
+            .tty()
+            .get_device_from_node(node)
+            .unwrap()
+            .lease_request(request)
+    }
+
+    fn new_active_lease(&mut self, node: DrmNode, lease: DrmLease) {
+        debug!("Lease success");
+        self.backend
+            .tty()
+            .get_device_from_node(node)
+            .unwrap()
+            .new_lease(lease);
+    }
+
+    fn lease_destroyed(&mut self, node: DrmNode, lease_id: u32) {
+        debug!("Destroyed lease");
+        self.backend
+            .tty()
+            .get_device_from_node(node)
+            .unwrap()
+            .remove_lease(lease_id);
+    }
+}
+delegate_drm_lease!(State);
+
+delegate_viewporter!(State);
+
+impl GammaControlHandler for State {
+    fn gamma_control_manager_state(&mut self) -> &mut GammaControlManagerState {
+        &mut self.niri.gamma_control_manager_state
+    }
+
+    fn get_gamma_size(&mut self, output: &Output) -> Option<u32> {
+        match self.backend.tty().get_gamma_size(output) {
+            Ok(0) => None, // Setting gamma is not supported.
+            Ok(size) => Some(size),
+            Err(err) => {
+                warn!(
+                    "error getting gamma size for output {}: {err:?}",
+                    output.name()
+                );
+                None
+            }
+        }
+    }
+
+    fn set_gamma(&mut self, output: &Output, ramp: Option<Vec<u16>>) -> Option<()> {
+        match self.backend.tty().set_gamma(output, ramp) {
+            Ok(()) => Some(()),
+            Err(err) => {
+                warn!("error setting gamma for output {}: {err:?}", output.name());
+                None
+            }
+        }
+    }
+}
+delegate_gamma_control!(State);

src/handlers/xdg_shell.rs

@@ -12,7 +12,11 @@ use smithay::reexports::wayland_server::protocol::wl_output;
 use smithay::reexports::wayland_server::protocol::wl_seat::WlSeat;
 use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
 use smithay::utils::{Logical, Rectangle, Serial};
-use smithay::wayland::compositor::{send_surface_state, with_states};
+use smithay::wayland::compositor::{
+    add_pre_commit_hook, send_surface_state, with_states, BufferAssignment, HookId,
+    SurfaceAttributes,
+};
+use smithay::wayland::input_method::InputMethodSeat;
 use smithay::wayland::shell::kde::decoration::{KdeDecorationHandler, KdeDecorationState};
 use smithay::wayland::shell::wlr_layer::Layer;
 use smithay::wayland::shell::xdg::decoration::XdgDecorationHandler;
@@ -20,10 +24,15 @@ use smithay::wayland::shell::xdg::{
     PopupSurface, PositionerState, ToplevelSurface, XdgPopupSurfaceData, XdgShellHandler,
     XdgShellState, XdgToplevelSurfaceData,
 };
-use smithay::{delegate_kde_decoration, delegate_xdg_decoration, delegate_xdg_shell};
+use smithay::wayland::xdg_foreign::{XdgForeignHandler, XdgForeignState};
+use smithay::{
+    delegate_kde_decoration, delegate_xdg_decoration, delegate_xdg_foreign, delegate_xdg_shell,
+};
 
+use crate::layout::workspace::ColumnWidth;
+use crate::layout::LayoutElement as _;
 use crate::niri::{PopupGrabState, State};
-use crate::utils::clone2;
+use crate::window::{InitialConfigureState, ResolvedWindowRules, Unmapped, WindowRef};
 
 impl XdgShellHandler for State {
     fn xdg_shell_state(&mut self) -> &mut XdgShellState {
@@ -32,27 +41,8 @@ impl XdgShellHandler for State {
 
     fn new_toplevel(&mut self, surface: ToplevelSurface) {
         let wl_surface = surface.wl_surface().clone();
-        let window = Window::new(surface);
+        let unmapped = Unmapped::new(Window::new_wayland_window(surface));
-
+        let existing = self.niri.unmapped_windows.insert(wl_surface, unmapped);
-        // Tell the surface the preferred size and bounds for its likely output.
-        if let Some(ws) = self.niri.layout.active_workspace() {
-            ws.configure_new_window(&window);
-        }
-
-        // If the user prefers no CSD, it's a reasonable assumption that they would prefer to get
-        // rid of the various client-side rounded corners also by using the tiled state.
-        let config = self.niri.config.borrow();
-        if config.prefer_no_csd {
-            window.toplevel().with_pending_state(|state| {
-                state.states.set(xdg_toplevel::State::TiledLeft);
-                state.states.set(xdg_toplevel::State::TiledRight);
-                state.states.set(xdg_toplevel::State::TiledTop);
-                state.states.set(xdg_toplevel::State::TiledBottom);
-            });
-        }
-
-        // At the moment of creation, xdg toplevels must have no buffer.
-        let existing = self.niri.unmapped_windows.insert(wl_surface, window);
         assert!(existing.is_none());
     }
 
@@ -94,6 +84,15 @@ impl XdgShellHandler for State {
     }
 
     fn grab(&mut self, surface: PopupSurface, _seat: WlSeat, serial: Serial) {
+        // HACK: ignore grabs (pretend they work without actually grabbing) if the input method has
+        // a grab. It will likely need refactors in Smithay to support properly since grabs just
+        // replace each other.
+        // FIXME: do this properly.
+        if self.niri.seat.input_method().keyboard_grabbed() {
+            trace!("ignoring popup grab because IME has keyboard grabbed");
+            return;
+        }
+
         let popup = PopupKind::Xdg(surface);
         let Ok(root) = find_popup_root_surface(&popup) else {
             return;
@@ -185,9 +184,11 @@ impl XdgShellHandler for State {
     fn maximize_request(&mut self, surface: ToplevelSurface) {
         // FIXME
 
-        // The protocol demands us to always reply with a configure,
+        // A configure is required in response to this event. However, if an initial configure
-        // regardless of we fulfilled the request or not
+        // wasn't sent, then we will send this as part of the initial configure later.
-        surface.send_configure();
+        if initial_configure_sent(&surface) {
+            surface.send_configure();
+        }
     }
 
     fn unmaximize_request(&mut self, _surface: ToplevelSurface) {
@@ -196,46 +197,167 @@ impl XdgShellHandler for State {
 
     fn fullscreen_request(
         &mut self,
-        surface: ToplevelSurface,
+        toplevel: ToplevelSurface,
         wl_output: Option<wl_output::WlOutput>,
     ) {
-        if surface
+        let requested_output = wl_output.as_ref().and_then(Output::from_resource);
-            .current_state()
-            .capabilities
-            .contains(xdg_toplevel::WmCapabilities::Fullscreen)
-        {
-            if let Some((window, current_output)) = self
-                .niri
-                .layout
-                .find_window_and_output(surface.wl_surface())
-            {
-                let window = window.clone();
 
-                if let Some(requested_output) = wl_output.as_ref().and_then(Output::from_resource) {
+        if let Some((mapped, current_output)) = self
-                    if &requested_output != current_output {
-                        self.niri
-                            .layout
-                            .move_window_to_output(window.clone(), &requested_output);
-                    }
-                }
-
-                self.niri.layout.set_fullscreen(&window, true);
-            }
-        }
-
-        // The protocol demands us to always reply with a configure,
-        // regardless of we fulfilled the request or not
-        surface.send_configure();
-    }
-
-    fn unfullscreen_request(&mut self, surface: ToplevelSurface) {
-        if let Some((window, _)) = self
             .niri
             .layout
-            .find_window_and_output(surface.wl_surface())
+            .find_window_and_output(toplevel.wl_surface())
         {
-            let window = window.clone();
+            let window = mapped.window.clone();
+
+            if let Some(requested_output) = requested_output {
+                if &requested_output != current_output {
+                    self.niri
+                        .layout
+                        .move_window_to_output(&window, &requested_output);
+                }
+            }
+
+            self.niri.layout.set_fullscreen(&window, true);
+
+            // A configure is required in response to this event regardless if there are pending
+            // changes.
+            toplevel.send_configure();
+        } else if let Some(unmapped) = self.niri.unmapped_windows.get_mut(toplevel.wl_surface()) {
+            match &mut unmapped.state {
+                InitialConfigureState::NotConfigured { wants_fullscreen } => {
+                    *wants_fullscreen = Some(requested_output);
+
+                    // The required configure will be the initial configure.
+                }
+                InitialConfigureState::Configured { output, .. } => {
+                    // Figure out the monitor following a similar logic to initial configure.
+                    // FIXME: deduplicate.
+                    let mon = requested_output
+                        .as_ref()
+                        // If none requested, try currently configured output.
+                        .or(output.as_ref())
+                        .and_then(|o| self.niri.layout.monitor_for_output(o))
+                        .map(|mon| (mon, false))
+                        // If not, check if we have a parent with a monitor.
+                        .or_else(|| {
+                            toplevel
+                                .parent()
+                                .and_then(|parent| self.niri.layout.find_window_and_output(&parent))
+                                .map(|(_win, output)| output)
+                                .and_then(|o| self.niri.layout.monitor_for_output(o))
+                                .map(|mon| (mon, true))
+                        })
+                        // If not, fall back to the active monitor.
+                        .or_else(|| {
+                            self.niri
+                                .layout
+                                .active_monitor_ref()
+                                .map(|mon| (mon, false))
+                        });
+
+                    *output = mon
+                        .filter(|(_, parent)| !parent)
+                        .map(|(mon, _)| mon.output.clone());
+                    let mon = mon.map(|(mon, _)| mon);
+
+                    let ws = mon
+                        .map(|mon| mon.active_workspace_ref())
+                        .or_else(|| self.niri.layout.active_workspace());
+
+                    if let Some(ws) = ws {
+                        toplevel.with_pending_state(|state| {
+                            state.states.set(xdg_toplevel::State::Fullscreen);
+                        });
+                        ws.configure_new_window(&unmapped.window, None);
+                    }
+
+                    // We already sent the initial configure, so we need to reconfigure.
+                    toplevel.send_configure();
+                }
+            }
+        } else {
+            error!("couldn't find the toplevel in fullscreen_request()");
+            toplevel.send_configure();
+        }
+    }
+
+    fn unfullscreen_request(&mut self, toplevel: ToplevelSurface) {
+        if let Some((mapped, _)) = self
+            .niri
+            .layout
+            .find_window_and_output(toplevel.wl_surface())
+        {
+            let window = mapped.window.clone();
             self.niri.layout.set_fullscreen(&window, false);
+
+            // A configure is required in response to this event regardless if there are pending
+            // changes.
+            toplevel.send_configure();
+        } else if let Some(unmapped) = self.niri.unmapped_windows.get_mut(toplevel.wl_surface()) {
+            match &mut unmapped.state {
+                InitialConfigureState::NotConfigured { wants_fullscreen } => {
+                    *wants_fullscreen = None;
+
+                    // The required configure will be the initial configure.
+                }
+                InitialConfigureState::Configured {
+                    width,
+                    is_full_width,
+                    output,
+                    ..
+                } => {
+                    // Figure out the monitor following a similar logic to initial configure.
+                    // FIXME: deduplicate.
+                    let mon = output
+                        .as_ref()
+                        .and_then(|o| self.niri.layout.monitor_for_output(o))
+                        .map(|mon| (mon, false))
+                        // If not, check if we have a parent with a monitor.
+                        .or_else(|| {
+                            toplevel
+                                .parent()
+                                .and_then(|parent| self.niri.layout.find_window_and_output(&parent))
+                                .map(|(_win, output)| output)
+                                .and_then(|o| self.niri.layout.monitor_for_output(o))
+                                .map(|mon| (mon, true))
+                        })
+                        // If not, fall back to the active monitor.
+                        .or_else(|| {
+                            self.niri
+                                .layout
+                                .active_monitor_ref()
+                                .map(|mon| (mon, false))
+                        });
+
+                    *output = mon
+                        .filter(|(_, parent)| !parent)
+                        .map(|(mon, _)| mon.output.clone());
+                    let mon = mon.map(|(mon, _)| mon);
+
+                    let ws = mon
+                        .map(|mon| mon.active_workspace_ref())
+                        .or_else(|| self.niri.layout.active_workspace());
+
+                    if let Some(ws) = ws {
+                        toplevel.with_pending_state(|state| {
+                            state.states.unset(xdg_toplevel::State::Fullscreen);
+                        });
+
+                        let configure_width = if *is_full_width {
+                            Some(ColumnWidth::Proportion(1.))
+                        } else {
+                            *width
+                        };
+                        ws.configure_new_window(&unmapped.window, configure_width);
+                    }
+
+                    // We already sent the initial configure, so we need to reconfigure.
+                    toplevel.send_configure();
+                }
+            }
+        } else {
+            error!("couldn't find the toplevel in unfullscreen_request()");
+            toplevel.send_configure();
         }
     }
 
@@ -255,22 +377,49 @@ impl XdgShellHandler for State {
             .layout
             .find_window_and_output(surface.wl_surface());
 
-        let Some((window, output)) = win_out.map(clone2) else {
+        let Some((mapped, output)) = win_out else {
             // I have no idea how this can happen, but I saw it happen once, in a weird interaction
             // involving laptop going to sleep and resuming.
             error!("toplevel missing from both unmapped_windows and layout");
             return;
         };
+        let window = mapped.window.clone();
+        let output = output.clone();
+
+        self.backend.with_primary_renderer(|renderer| {
+            mapped.store_unmap_snapshot_if_empty(renderer);
+        });
+        self.backend.with_primary_renderer(|renderer| {
+            self.niri
+                .layout
+                .start_close_animation_for_window(renderer, &window);
+        });
+
+        let active_window = self.niri.layout.active_window().map(|(m, _)| &m.window);
+        let was_active = active_window == Some(&window);
 
         self.niri.layout.remove_window(&window);
-        self.niri.queue_redraw(output);
+
+        if was_active {
+            self.maybe_warp_cursor_to_focus();
+        }
+
+        self.niri.queue_redraw(&output);
     }
 
     fn popup_destroyed(&mut self, surface: PopupSurface) {
         if let Some(output) = self.output_for_popup(&PopupKind::Xdg(surface)) {
-            self.niri.queue_redraw(output.clone());
+            self.niri.queue_redraw(&output.clone());
         }
     }
+
+    fn app_id_changed(&mut self, toplevel: ToplevelSurface) {
+        self.update_window_rules(&toplevel);
+    }
+
+    fn title_changed(&mut self, toplevel: ToplevelSurface) {
+        self.update_window_rules(&toplevel);
+    }
 }
 
 delegate_xdg_shell!(State);
@@ -323,14 +472,14 @@ impl KdeDecorationHandler for State {
         &self.niri.kde_decoration_state
     }
 }
-
 delegate_kde_decoration!(State);
 
-pub fn send_initial_configure_if_needed(toplevel: &ToplevelSurface) {
+impl XdgForeignHandler for State {
-    if !initial_configure_sent(toplevel) {
+    fn xdg_foreign_state(&mut self) -> &mut XdgForeignState {
-        toplevel.send_configure();
+        &mut self.niri.xdg_foreign_state
     }
 }
+delegate_xdg_foreign!(State);
 
 fn initial_configure_sent(toplevel: &ToplevelSurface) -> bool {
     with_states(toplevel.wl_surface(), |states| {
@@ -345,6 +494,132 @@ fn initial_configure_sent(toplevel: &ToplevelSurface) -> bool {
 }
 
 impl State {
+    pub fn send_initial_configure(&mut self, toplevel: &ToplevelSurface) {
+        let _span = tracy_client::span!("State::send_initial_configure");
+
+        let Some(unmapped) = self.niri.unmapped_windows.get_mut(toplevel.wl_surface()) else {
+            error!("window must be present in unmapped_windows in send_initial_configure()");
+            return;
+        };
+
+        let config = self.niri.config.borrow();
+        let rules =
+            ResolvedWindowRules::compute(&config.window_rules, WindowRef::Unmapped(unmapped));
+
+        let Unmapped { window, state } = unmapped;
+
+        let InitialConfigureState::NotConfigured { wants_fullscreen } = state else {
+            error!("window must not be already configured in send_initial_configure()");
+            return;
+        };
+
+        // Pick the target monitor. First, check if we had an output set in the window rules.
+        let mon = rules
+            .open_on_output
+            .as_deref()
+            .and_then(|name| self.niri.output_by_name.get(name))
+            .and_then(|o| self.niri.layout.monitor_for_output(o));
+
+        // If not, check if the window requested one for fullscreen.
+        let mon = mon.or_else(|| {
+            wants_fullscreen
+                .as_ref()
+                .and_then(|x| x.as_ref())
+                // The monitor might not exist if the output was disconnected.
+                .and_then(|o| self.niri.layout.monitor_for_output(o))
+        });
+
+        // If not, check if this is a dialog with a parent, to place it next to the parent.
+        let mon = mon.map(|mon| (mon, false)).or_else(|| {
+            toplevel
+                .parent()
+                .and_then(|parent| self.niri.layout.find_window_and_output(&parent))
+                .map(|(_win, output)| output)
+                .and_then(|o| self.niri.layout.monitor_for_output(o))
+                .map(|mon| (mon, true))
+        });
+
+        // If not, use the active monitor.
+        let mon = mon.or_else(|| {
+            self.niri
+                .layout
+                .active_monitor_ref()
+                .map(|mon| (mon, false))
+        });
+
+        // If we're following the parent, don't set the target output, so that when the window is
+        // mapped, it fetches the possibly changed parent's output again, and shows up there.
+        let output = mon
+            .filter(|(_, parent)| !parent)
+            .map(|(mon, _)| mon.output.clone());
+        let mon = mon.map(|(mon, _)| mon);
+
+        let mut width = None;
+        let is_full_width = rules.open_maximized.unwrap_or(false);
+
+        // Tell the surface the preferred size and bounds for its likely output.
+        let ws = mon
+            .map(|mon| mon.active_workspace_ref())
+            .or_else(|| self.niri.layout.active_workspace());
+
+        if let Some(ws) = ws {
+            // Set a fullscreen state based on window request and window rule.
+            if (wants_fullscreen.is_some() && rules.open_fullscreen.is_none())
+                || rules.open_fullscreen == Some(true)
+            {
+                toplevel.with_pending_state(|state| {
+                    state.states.set(xdg_toplevel::State::Fullscreen);
+                });
+            }
+
+            width = ws.resolve_default_width(rules.default_width);
+
+            let configure_width = if is_full_width {
+                Some(ColumnWidth::Proportion(1.))
+            } else {
+                width
+            };
+            ws.configure_new_window(window, configure_width);
+        }
+
+        // If the user prefers no CSD, it's a reasonable assumption that they would prefer to get
+        // rid of the various client-side rounded corners also by using the tiled state.
+        if config.prefer_no_csd {
+            toplevel.with_pending_state(|state| {
+                state.states.set(xdg_toplevel::State::TiledLeft);
+                state.states.set(xdg_toplevel::State::TiledRight);
+                state.states.set(xdg_toplevel::State::TiledTop);
+                state.states.set(xdg_toplevel::State::TiledBottom);
+            });
+        }
+
+        // Set the configured settings.
+        *state = InitialConfigureState::Configured {
+            rules,
+            width,
+            is_full_width,
+            output,
+        };
+
+        toplevel.send_configure();
+    }
+
+    pub fn queue_initial_configure(&self, toplevel: ToplevelSurface) {
+        // Send the initial configure in an idle, in case the client sent some more info after the
+        // initial commit.
+        self.niri.event_loop.insert_idle(move |state| {
+            if !toplevel.alive() {
+                return;
+            }
+
+            if let Some(unmapped) = state.niri.unmapped_windows.get(toplevel.wl_surface()) {
+                if unmapped.needs_initial_configure() {
+                    state.send_initial_configure(&toplevel);
+                }
+            }
+        });
+    }
+
     /// Should be called on `WlSurface::commit`
     pub fn popups_handle_commit(&mut self, surface: &WlSurface) {
         self.niri.popups.commit(surface);
@@ -394,8 +669,8 @@ impl State {
         };
 
         // Figure out if the root is a window or a layer surface.
-        if let Some((window, output)) = self.niri.layout.find_window_and_output(&root) {
+        if let Some((mapped, output)) = self.niri.layout.find_window_and_output(&root) {
-            self.unconstrain_window_popup(popup, window, output);
+            self.unconstrain_window_popup(popup, &mapped.window, output);
         } else if let Some((layer_surface, output)) = self.niri.layout.outputs().find_map(|o| {
             let map = layer_map_for_output(o);
             let layer_surface = map.layer_for_surface(&root, WindowSurfaceType::TOPLEVEL)?;
@@ -451,7 +726,9 @@ impl State {
     pub fn update_reactive_popups(&self, window: &Window, output: &Output) {
         let _span = tracy_client::span!("Niri::update_reactive_popups");
 
-        for (popup, _) in PopupManager::popups_for_surface(window.toplevel().wl_surface()) {
+        for (popup, _) in PopupManager::popups_for_surface(
+            window.toplevel().expect("no x11 support").wl_surface(),
+        ) {
             match popup {
                 PopupKind::Xdg(ref popup) => {
                     if popup.with_pending_state(|state| state.positioner.reactive) {
@@ -465,6 +742,34 @@ impl State {
             }
         }
     }
+
+    pub fn update_window_rules(&mut self, toplevel: &ToplevelSurface) {
+        let config = self.niri.config.borrow();
+        let window_rules = &config.window_rules;
+
+        if let Some(unmapped) = self.niri.unmapped_windows.get_mut(toplevel.wl_surface()) {
+            let new_rules =
+                ResolvedWindowRules::compute(window_rules, WindowRef::Unmapped(unmapped));
+            if let InitialConfigureState::Configured { rules, .. } = &mut unmapped.state {
+                *rules = new_rules;
+            }
+        } else if let Some((mapped, output)) = self
+            .niri
+            .layout
+            .find_window_and_output_mut(toplevel.wl_surface())
+        {
+            if mapped.recompute_window_rules(window_rules) {
+                drop(config);
+                let output = output.cloned();
+                let window = mapped.window.clone();
+                self.niri.layout.update_window(&window);
+
+                if let Some(output) = output {
+                    self.niri.queue_redraw(&output);
+                }
+            }
+        }
+    }
 }
 
 fn unconstrain_with_padding(
@@ -507,3 +812,53 @@ fn unconstrain_with_padding(
     // Could not unconstrain into the padded target, so resort to the regular one.
     positioner.get_unconstrained_geometry(target)
 }
+
+pub fn add_mapped_toplevel_pre_commit_hook(toplevel: &ToplevelSurface) -> HookId {
+    add_pre_commit_hook::<State, _>(toplevel.wl_surface(), move |state, _dh, surface| {
+        let _span = tracy_client::span!("mapped toplevel pre-commit");
+
+        let Some((mapped, _)) = state.niri.layout.find_window_and_output_mut(surface) else {
+            error!("pre-commit hook for mapped surfaces must be removed upon unmapping");
+            return;
+        };
+
+        let (got_unmapped, commit_serial) = with_states(surface, |states| {
+            let attrs = states.cached_state.pending::<SurfaceAttributes>();
+            let got_unmapped = matches!(attrs.buffer, Some(BufferAssignment::Removed));
+
+            let role = states
+                .data_map
+                .get::<XdgToplevelSurfaceData>()
+                .unwrap()
+                .lock()
+                .unwrap();
+
+            (got_unmapped, role.configure_serial)
+        });
+
+        let animate = if let Some(serial) = commit_serial {
+            mapped.should_animate_commit(serial)
+        } else {
+            error!("commit on a mapped surface without a configured serial");
+            false
+        };
+
+        if got_unmapped {
+            state.backend.with_primary_renderer(|renderer| {
+                mapped.store_unmap_snapshot_if_empty(renderer);
+            });
+        } else {
+            // The toplevel remains mapped; clear any stored unmap snapshot.
+            let _ = mapped.take_unmap_snapshot();
+
+            if animate {
+                state.backend.with_primary_renderer(|renderer| {
+                    mapped.store_animation_snapshot(renderer);
+                });
+
+                let window = mapped.window.clone();
+                state.niri.layout.prepare_for_resize_animation(&window);
+            }
+        }
+    })
+}

src/ipc/client.rs

@@ -1,46 +1,101 @@
-use std::env;
+use anyhow::{anyhow, bail, Context};
-use std::io::{Read, Write};
+use niri_ipc::{LogicalOutput, Mode, Output, Request, Response, Socket, Transform};
-use std::net::Shutdown;
+use serde_json::json;
-use std::os::unix::net::UnixStream;
 
-use anyhow::{bail, Context};
+use crate::cli::Msg;
-use niri_ipc::{Mode, Output, Request, Response};
+use crate::utils::version;
-
-use crate::Msg;
 
 pub fn handle_msg(msg: Msg, json: bool) -> anyhow::Result<()> {
-    let socket_path = env::var_os(niri_ipc::SOCKET_PATH_ENV).with_context(|| {
+    let request = match &msg {
-        format!(
+        Msg::Version => Request::Version,
-            "{} is not set, are you running this within niri?",
+        Msg::Outputs => Request::Outputs,
-            niri_ipc::SOCKET_PATH_ENV
+        Msg::FocusedWindow => Request::FocusedWindow,
-        )
+        Msg::Action { action } => Request::Action(action.clone()),
+        Msg::RequestError => Request::ReturnError,
+    };
+
+    let socket = Socket::connect().context("error connecting to the niri socket")?;
+
+    let reply = socket
+        .send(request)
+        .context("error communicating with niri")?;
+
+    let compositor_version = match reply {
+        Err(_) if !matches!(msg, Msg::Version) => {
+            // If we got an error, it might be that the CLI is a different version from the running
+            // niri instance. Request the running instance version to compare and print a message.
+            Socket::connect()
+                .and_then(|socket| socket.send(Request::Version))
+                .ok()
+        }
+        _ => None,
+    };
+
+    // Default SIGPIPE so that our prints don't panic on stdout closing.
+    unsafe {
+        libc::signal(libc::SIGPIPE, libc::SIG_DFL);
+    }
+
+    let response = reply.map_err(|err_msg| {
+        // Check for CLI-server version mismatch to add helpful context.
+        match compositor_version {
+            Some(Ok(Response::Version(compositor_version))) => {
+                let cli_version = version();
+                if cli_version != compositor_version {
+                    eprintln!("Running niri compositor has a different version from the niri CLI:");
+                    eprintln!("Compositor version: {compositor_version}");
+                    eprintln!("CLI version:        {cli_version}");
+                    eprintln!("Did you forget to restart niri after an update?");
+                    eprintln!();
+                }
+            }
+            Some(_) => {
+                eprintln!("Unable to get the running niri compositor version.");
+                eprintln!("Did you forget to restart niri after an update?");
+                eprintln!();
+            }
+            None => {
+                // Communication error, or the original request was already a version request.
+                // Don't add irrelevant context.
+            }
+        }
+
+        anyhow!(err_msg).context("niri returned an error")
     })?;
 
-    let mut stream =
-        UnixStream::connect(socket_path).context("error connecting to {socket_path}")?;
-
-    let request = match msg {
-        Msg::Outputs => Request::Outputs,
-    };
-    let mut buf = serde_json::to_vec(&request).unwrap();
-    stream
-        .write_all(&buf)
-        .context("error writing IPC request")?;
-    stream
-        .shutdown(Shutdown::Write)
-        .context("error closing IPC stream for writing")?;
-
-    buf.clear();
-    stream
-        .read_to_end(&mut buf)
-        .context("error reading IPC response")?;
-
-    let response = serde_json::from_slice(&buf).context("error parsing IPC response")?;
     match msg {
+        Msg::RequestError => {
+            bail!("unexpected response: expected an error, got {response:?}");
+        }
+        Msg::Version => {
+            let Response::Version(compositor_version) = response else {
+                bail!("unexpected response: expected Version, got {response:?}");
+            };
+
+            let cli_version = version();
+
+            if json {
+                println!(
+                    "{}",
+                    json!({
+                        "compositor": compositor_version,
+                        "cli": cli_version,
+                    })
+                );
+                return Ok(());
+            }
+
+            if cli_version != compositor_version {
+                eprintln!("Running niri compositor has a different version from the niri CLI.");
+                eprintln!("Did you forget to restart niri after an update?");
+                eprintln!();
+            }
+
+            println!("Compositor version: {compositor_version}");
+            println!("CLI version:        {cli_version}");
+        }
         Msg::Outputs => {
-            #[allow(irrefutable_let_patterns)]
+            let Response::Outputs(outputs) = response else {
-            let Response::Outputs(outputs) = response
-            else {
                 bail!("unexpected response: expected Outputs, got {response:?}");
             };
 
@@ -62,6 +117,9 @@ pub fn handle_msg(msg: Msg, json: bool) -> anyhow::Result<()> {
                     physical_size,
                     modes,
                     current_mode,
+                    vrr_supported,
+                    vrr_enabled,
+                    logical,
                 } = output;
 
                 println!(r#"Output "{connector}" ({make} - {model} - {name})"#);
@@ -74,32 +132,111 @@ pub fn handle_msg(msg: Msg, json: bool) -> anyhow::Result<()> {
                         width,
                         height,
                         refresh_rate,
+                        is_preferred,
                     } = mode;
                     let refresh = refresh_rate as f64 / 1000.;
-                    println!("  Current mode: {width}x{height} @ {refresh:.3} Hz");
+                    let preferred = if is_preferred { " (preferred)" } else { "" };
+                    println!("  Current mode: {width}x{height} @ {refresh:.3} Hz{preferred}");
                 } else {
                     println!("  Disabled");
                 }
 
+                if vrr_supported {
+                    let enabled = if vrr_enabled { "enabled" } else { "disabled" };
+                    println!("  Variable refresh rate: supported, {enabled}");
+                } else {
+                    println!("  Variable refresh rate: not supported");
+                }
+
                 if let Some((width, height)) = physical_size {
                     println!("  Physical size: {width}x{height} mm");
                 } else {
                     println!("  Physical size: unknown");
                 }
 
+                if let Some(logical) = logical {
+                    let LogicalOutput {
+                        x,
+                        y,
+                        width,
+                        height,
+                        scale,
+                        transform,
+                    } = logical;
+                    println!("  Logical position: {x}, {y}");
+                    println!("  Logical size: {width}x{height}");
+                    println!("  Scale: {scale}");
+
+                    let transform = match transform {
+                        Transform::Normal => "normal",
+                        Transform::_90 => "90° counter-clockwise",
+                        Transform::_180 => "180°",
+                        Transform::_270 => "270° counter-clockwise",
+                        Transform::Flipped => "flipped horizontally",
+                        Transform::Flipped90 => "90° counter-clockwise, flipped horizontally",
+                        Transform::Flipped180 => "flipped vertically",
+                        Transform::Flipped270 => "270° counter-clockwise, flipped horizontally",
+                    };
+                    println!("  Transform: {transform}");
+                }
+
                 println!("  Available modes:");
-                for mode in modes {
+                for (idx, mode) in modes.into_iter().enumerate() {
                     let Mode {
                         width,
                         height,
                         refresh_rate,
+                        is_preferred,
                     } = mode;
                     let refresh = refresh_rate as f64 / 1000.;
-                    println!("    {width}x{height}@{refresh:.3}");
+
+                    let is_current = Some(idx) == current_mode;
+                    let qualifier = match (is_current, is_preferred) {
+                        (true, true) => " (current, preferred)",
+                        (true, false) => " (current)",
+                        (false, true) => " (preferred)",
+                        (false, false) => "",
+                    };
+
+                    println!("    {width}x{height}@{refresh:.3}{qualifier}");
                 }
                 println!();
             }
         }
+        Msg::FocusedWindow => {
+            let Response::FocusedWindow(window) = response else {
+                bail!("unexpected response: expected FocusedWindow, got {response:?}");
+            };
+
+            if json {
+                let window = serde_json::to_string(&window).context("error formatting response")?;
+                println!("{window}");
+                return Ok(());
+            }
+
+            if let Some(window) = window {
+                println!("Focused window:");
+
+                if let Some(title) = window.title {
+                    println!("  Title: \"{title}\"");
+                } else {
+                    println!("  Title: (unset)");
+                }
+
+                if let Some(app_id) = window.app_id {
+                    println!("  App ID: \"{app_id}\"");
+                } else {
+                    println!("  App ID: (unset)");
+                }
+            } else {
+                println!("No window is focused.");
+            }
+        }
+        Msg::Action { .. } => {
+            let Response::Handled = response else {
+                bail!("unexpected response: expected Handled, got {response:?}");
+            };
+        }
     }
 
     Ok(())

src/ipc/server.rs

@@ -1,8 +1,6 @@
-use std::cell::RefCell;
-use std::collections::HashMap;
 use std::os::unix::net::{UnixListener, UnixStream};
 use std::path::PathBuf;
-use std::rc::Rc;
+use std::sync::{Arc, Mutex};
 use std::{env, io, process};
 
 use anyhow::Context;
@@ -10,19 +8,26 @@ use calloop::io::Async;
 use directories::BaseDirs;
 use futures_util::io::{AsyncReadExt, BufReader};
 use futures_util::{AsyncBufReadExt, AsyncWriteExt};
-use niri_ipc::{Request, Response};
+use niri_ipc::{Reply, Request, Response};
+use smithay::desktop::Window;
 use smithay::reexports::calloop::generic::Generic;
 use smithay::reexports::calloop::{Interest, LoopHandle, Mode, PostAction};
 use smithay::reexports::rustix::fs::unlink;
+use smithay::wayland::compositor::with_states;
+use smithay::wayland::shell::xdg::XdgToplevelSurfaceData;
 
+use crate::backend::IpcOutputMap;
 use crate::niri::State;
+use crate::utils::version;
 
 pub struct IpcServer {
     pub socket_path: PathBuf,
 }
 
 struct ClientCtx {
-    ipc_outputs: Rc<RefCell<HashMap<String, niri_ipc::Output>>>,
+    event_loop: LoopHandle<'static, State>,
+    ipc_outputs: Arc<Mutex<IpcOutputMap>>,
+    ipc_focused_window: Arc<Mutex<Option<Window>>>,
 }
 
 impl IpcServer {
@@ -85,7 +90,9 @@ fn on_new_ipc_client(state: &mut State, stream: UnixStream) {
     };
 
     let ctx = ClientCtx {
+        event_loop: state.niri.event_loop.clone(),
         ipc_outputs: state.backend.ipc_outputs(),
+        ipc_focused_window: state.niri.ipc_focused_window.clone(),
     };
 
     let future = async move {
@@ -108,20 +115,61 @@ async fn handle_client(ctx: ClientCtx, stream: Async<'_, UnixStream>) -> anyhow:
         .await
         .context("error reading request")?;
 
-    let request: Request = serde_json::from_str(&buf).context("error parsing request")?;
+    let request = serde_json::from_str(&buf)
+        .context("error parsing request")
+        .map_err(|err| err.to_string());
+    let requested_error = matches!(request, Ok(Request::ReturnError));
 
-    let response = match request {
+    let reply = request.and_then(|request| process(&ctx, request));
-        Request::Outputs => {
+
-            let ipc_outputs = ctx.ipc_outputs.borrow().clone();
+    if let Err(err) = &reply {
-            Response::Outputs(ipc_outputs)
+        if !requested_error {
+            warn!("error processing IPC request: {err:?}");
         }
-    };
+    }
 
-    let buf = serde_json::to_vec(&response).context("error formatting response")?;
+    let buf = serde_json::to_vec(&reply).context("error formatting reply")?;
-    write
+    write.write_all(&buf).await.context("error writing reply")?;
-        .write_all(&buf)
-        .await
-        .context("error writing response")?;
 
     Ok(())
 }
+
+fn process(ctx: &ClientCtx, request: Request) -> Reply {
+    let response = match request {
+        Request::ReturnError => return Err(String::from("example compositor error")),
+        Request::Version => Response::Version(version()),
+        Request::Outputs => {
+            let ipc_outputs = ctx.ipc_outputs.lock().unwrap().clone();
+            Response::Outputs(ipc_outputs)
+        }
+        Request::FocusedWindow => {
+            let window = ctx.ipc_focused_window.lock().unwrap().clone();
+            let window = window.map(|window| {
+                let wl_surface = window.toplevel().expect("no X11 support").wl_surface();
+                with_states(wl_surface, |states| {
+                    let role = states
+                        .data_map
+                        .get::<XdgToplevelSurfaceData>()
+                        .unwrap()
+                        .lock()
+                        .unwrap();
+
+                    niri_ipc::Window {
+                        title: role.title.clone(),
+                        app_id: role.app_id.clone(),
+                    }
+                })
+            });
+            Response::FocusedWindow(window)
+        }
+        Request::Action(action) => {
+            let action = niri_config::Action::from(action);
+            ctx.event_loop.insert_idle(move |state| {
+                state.do_action(action, false);
+            });
+            Response::Handled
+        }
+    };
+
+    Ok(response)
+}

src/layout/closing_window.rs

@@ -0,0 +1,164 @@
+use std::time::Duration;
+
+use anyhow::Context as _;
+use niri_config::BlockOutFrom;
+use smithay::backend::allocator::Fourcc;
+use smithay::backend::renderer::element::texture::{TextureBuffer, TextureRenderElement};
+use smithay::backend::renderer::element::utils::{
+    Relocate, RelocateRenderElement, RescaleRenderElement,
+};
+use smithay::backend::renderer::element::{Kind, RenderElement};
+use smithay::backend::renderer::gles::{GlesRenderer, GlesTexture};
+use smithay::utils::{Logical, Point, Scale, Transform};
+
+use crate::animation::Animation;
+use crate::niri_render_elements;
+use crate::render_helpers::primary_gpu_texture::PrimaryGpuTextureRenderElement;
+use crate::render_helpers::snapshot::RenderSnapshot;
+use crate::render_helpers::{render_to_encompassing_texture, RenderTarget};
+
+#[derive(Debug)]
+pub struct ClosingWindow {
+    /// Contents of the window.
+    buffer: TextureBuffer<GlesTexture>,
+
+    /// Blocked-out contents of the window.
+    blocked_out_buffer: TextureBuffer<GlesTexture>,
+
+    /// Where the window should be blocked out from.
+    block_out_from: Option<BlockOutFrom>,
+
+    /// Center of the window geometry.
+    center: Point<i32, Logical>,
+
+    /// Position in the workspace.
+    pos: Point<i32, Logical>,
+
+    /// How much the buffer should be offset.
+    buffer_offset: Point<i32, Logical>,
+
+    /// How much the blocked-out buffer should be offset.
+    blocked_out_buffer_offset: Point<i32, Logical>,
+
+    /// The closing animation.
+    anim: Animation,
+
+    /// Alpha the animation should start from.
+    starting_alpha: f32,
+
+    /// Scale the animation should start from.
+    starting_scale: f64,
+}
+
+niri_render_elements! {
+    ClosingWindowRenderElement => {
+        Texture = RelocateRenderElement<RescaleRenderElement<PrimaryGpuTextureRenderElement>>,
+    }
+}
+
+impl ClosingWindow {
+    #[allow(clippy::too_many_arguments)]
+    pub fn new<E: RenderElement<GlesRenderer>>(
+        renderer: &mut GlesRenderer,
+        snapshot: RenderSnapshot<E, E>,
+        scale: i32,
+        center: Point<i32, Logical>,
+        pos: Point<i32, Logical>,
+        anim: Animation,
+        starting_alpha: f32,
+        starting_scale: f64,
+    ) -> anyhow::Result<Self> {
+        let _span = tracy_client::span!("ClosingWindow::new");
+
+        let mut render_to_buffer = |elements: Vec<E>| -> anyhow::Result<_> {
+            let (texture, _sync_point, geo) = render_to_encompassing_texture(
+                renderer,
+                Scale::from(scale as f64),
+                Transform::Normal,
+                Fourcc::Abgr8888,
+                &elements,
+            )
+            .context("error rendering to texture")?;
+
+            let buffer =
+                TextureBuffer::from_texture(renderer, texture, scale, Transform::Normal, None);
+            let offset = geo.loc.to_logical(scale);
+
+            Ok((buffer, offset))
+        };
+
+        let (buffer, buffer_offset) =
+            render_to_buffer(snapshot.contents).context("error rendering contents")?;
+        let (blocked_out_buffer, blocked_out_buffer_offset) =
+            render_to_buffer(snapshot.blocked_out_contents)
+                .context("error rendering blocked-out contents")?;
+
+        Ok(Self {
+            buffer,
+            blocked_out_buffer,
+            block_out_from: snapshot.block_out_from,
+            center,
+            pos,
+            buffer_offset,
+            blocked_out_buffer_offset,
+            anim,
+            starting_alpha,
+            starting_scale,
+        })
+    }
+
+    pub fn advance_animations(&mut self, current_time: Duration) {
+        self.anim.set_current_time(current_time);
+    }
+
+    pub fn are_animations_ongoing(&self) -> bool {
+        !self.anim.is_clamped_done()
+    }
+
+    pub fn render(
+        &self,
+        view_pos: i32,
+        scale: Scale<f64>,
+        target: RenderTarget,
+    ) -> ClosingWindowRenderElement {
+        let val = self.anim.clamped_value();
+
+        let block_out = match self.block_out_from {
+            None => false,
+            Some(BlockOutFrom::Screencast) => target == RenderTarget::Screencast,
+            Some(BlockOutFrom::ScreenCapture) => target != RenderTarget::Output,
+        };
+        let (buffer, offset) = if block_out {
+            (&self.blocked_out_buffer, self.blocked_out_buffer_offset)
+        } else {
+            (&self.buffer, self.buffer_offset)
+        };
+
+        let elem = TextureRenderElement::from_texture_buffer(
+            Point::from((0., 0.)),
+            buffer,
+            Some(val.clamp(0., 1.) as f32 * self.starting_alpha),
+            None,
+            None,
+            Kind::Unspecified,
+        );
+
+        let elem = PrimaryGpuTextureRenderElement(elem);
+
+        let elem = RescaleRenderElement::from_element(
+            elem,
+            (self.center - offset).to_physical_precise_round(scale),
+            ((val / 5. + 0.8) * self.starting_scale).max(0.),
+        );
+
+        let mut location = self.pos + offset;
+        location.x -= view_pos;
+        let elem = RelocateRenderElement::from_element(
+            elem,
+            location.to_physical_precise_round(scale),
+            Relocate::Relative,
+        );
+
+        elem.into()
+    }
+}

src/layout/focus_ring.rs

@@ -1,64 +1,72 @@
 use std::iter::zip;
 
 use arrayvec::ArrayVec;
-use niri_config::{self, Color};
+use niri_config::GradientRelativeTo;
 use smithay::backend::renderer::element::solid::{SolidColorBuffer, SolidColorRenderElement};
 use smithay::backend::renderer::element::Kind;
-use smithay::utils::{Logical, Point, Scale, Size};
+use smithay::utils::{Logical, Point, Rectangle, Scale, Size};
+
+use crate::niri_render_elements;
+use crate::render_helpers::gradient::GradientRenderElement;
+use crate::render_helpers::renderer::NiriRenderer;
 
 #[derive(Debug)]
 pub struct FocusRing {
     buffers: [SolidColorBuffer; 4],
     locations: [Point<i32, Logical>; 4],
-    is_off: bool,
+    sizes: [Size<i32, Logical>; 4],
+    full_size: Size<i32, Logical>,
+    is_active: bool,
     is_border: bool,
-    width: i32,
+    config: niri_config::FocusRing,
-    active_color: Color,
-    inactive_color: Color,
 }
 
-pub type FocusRingRenderElement = SolidColorRenderElement;
+niri_render_elements! {
+    FocusRingRenderElement => {
+        SolidColor = SolidColorRenderElement,
+        Gradient = GradientRenderElement,
+    }
+}
 
 impl FocusRing {
     pub fn new(config: niri_config::FocusRing) -> Self {
         Self {
             buffers: Default::default(),
             locations: Default::default(),
-            is_off: config.off,
+            sizes: Default::default(),
+            full_size: Default::default(),
+            is_active: false,
             is_border: false,
-            width: config.width.into(),
+            config,
-            active_color: config.active_color,
-            inactive_color: config.inactive_color,
         }
     }
 
     pub fn update_config(&mut self, config: niri_config::FocusRing) {
-        self.is_off = config.off;
+        self.config = config;
-        self.width = config.width.into();
-        self.active_color = config.active_color;
-        self.inactive_color = config.inactive_color;
     }
 
-    pub fn update(
+    pub fn update(&mut self, win_size: Size<i32, Logical>, is_border: bool) {
-        &mut self,
+        let width = i32::from(self.config.width);
-        win_pos: Point<i32, Logical>,
+        self.full_size = win_size + Size::from((width * 2, width * 2));
-        win_size: Size<i32, Logical>,
-        is_border: bool,
-    ) {
-        if is_border {
-            self.buffers[0].resize((win_size.w + self.width * 2, self.width));
-            self.buffers[1].resize((win_size.w + self.width * 2, self.width));
-            self.buffers[2].resize((self.width, win_size.h));
-            self.buffers[3].resize((self.width, win_size.h));
 
-            self.locations[0] = win_pos + Point::from((-self.width, -self.width));
+        if is_border {
-            self.locations[1] = win_pos + Point::from((-self.width, win_size.h));
+            self.sizes[0] = Size::from((win_size.w + width * 2, width));
-            self.locations[2] = win_pos + Point::from((-self.width, 0));
+            self.sizes[1] = Size::from((win_size.w + width * 2, width));
-            self.locations[3] = win_pos + Point::from((win_size.w, 0));
+            self.sizes[2] = Size::from((width, win_size.h));
+            self.sizes[3] = Size::from((width, win_size.h));
+
+            for (buf, size) in zip(&mut self.buffers, self.sizes) {
+                buf.resize(size);
+            }
+
+            self.locations[0] = Point::from((-width, -width));
+            self.locations[1] = Point::from((-width, win_size.h));
+            self.locations[2] = Point::from((-width, 0));
+            self.locations[3] = Point::from((win_size.w, 0));
         } else {
-            let size = win_size + Size::from((self.width * 2, self.width * 2));
+            self.sizes[0] = self.full_size;
-            self.buffers[0].resize(size);
+            self.buffers[0].resize(self.sizes[0]);
-            self.locations[0] = win_pos - Point::from((self.width, self.width));
+            self.locations[0] = Point::from((-width, -width));
         }
 
         self.is_border = is_border;
@@ -66,50 +74,91 @@ impl FocusRing {
 
     pub fn set_active(&mut self, is_active: bool) {
         let color = if is_active {
-            self.active_color.into()
+            self.config.active_color.into()
         } else {
-            self.inactive_color.into()
+            self.config.inactive_color.into()
         };
 
         for buf in &mut self.buffers {
             buf.set_color(color);
         }
+
+        self.is_active = is_active;
     }
 
-    pub fn render(&self, scale: Scale<f64>) -> impl Iterator<Item = FocusRingRenderElement> {
+    pub fn render<R: NiriRenderer>(
+        &self,
+        renderer: &mut R,
+        location: Point<i32, Logical>,
+        scale: Scale<f64>,
+        view_size: Size<i32, Logical>,
+    ) -> impl Iterator<Item = FocusRingRenderElement> {
         let mut rv = ArrayVec::<_, 4>::new();
 
-        if self.is_off {
+        if self.config.off {
             return rv.into_iter();
         }
 
-        let mut push = |buffer, location: Point<i32, Logical>| {
+        let gradient = if self.is_active {
-            let elem = SolidColorRenderElement::from_buffer(
+            self.config.active_gradient
-                buffer,
+        } else {
-                location.to_physical_precise_round(scale),
+            self.config.inactive_gradient
-                scale,
+        };
-                1.,
+
-                Kind::Unspecified,
+        let full_rect = Rectangle::from_loc_and_size(location + self.locations[0], self.full_size);
-            );
+        let view_rect = Rectangle::from_loc_and_size((0, 0), view_size);
+
+        let mut push = |buffer, location: Point<i32, Logical>, size: Size<i32, Logical>| {
+            let elem = gradient.and_then(|gradient| {
+                let gradient_area = match gradient.relative_to {
+                    GradientRelativeTo::Window => full_rect,
+                    GradientRelativeTo::WorkspaceView => view_rect,
+                };
+                GradientRenderElement::new(
+                    renderer,
+                    scale,
+                    Rectangle::from_loc_and_size(location, size),
+                    gradient_area,
+                    gradient.from.into(),
+                    gradient.to.into(),
+                    ((gradient.angle as f32) - 90.).to_radians(),
+                )
+                .map(Into::into)
+            });
+
+            let elem = elem.unwrap_or_else(|| {
+                SolidColorRenderElement::from_buffer(
+                    buffer,
+                    location.to_physical_precise_round(scale),
+                    scale,
+                    1.,
+                    Kind::Unspecified,
+                )
+                .into()
+            });
             rv.push(elem);
         };
 
         if self.is_border {
-            for (buf, loc) in zip(&self.buffers, self.locations) {
+            for (buf, (loc, size)) in zip(&self.buffers, zip(self.locations, self.sizes)) {
-                push(buf, loc);
+                push(buf, location + loc, size);
             }
         } else {
-            push(&self.buffers[0], self.locations[0]);
+            push(
+                &self.buffers[0],
+                location + self.locations[0],
+                self.sizes[0],
+            );
         }
 
         rv.into_iter()
     }
 
     pub fn width(&self) -> i32 {
-        self.width
+        self.config.width.into()
     }
 
     pub fn is_off(&self) -> bool {
-        self.is_off
+        self.config.off
     }
 }

src/layout/monitor.rs

@@ -2,22 +2,33 @@ use std::cmp::min;
 use std::rc::Rc;
 use std::time::Duration;
 
-use niri_config::SizeChange;
+use niri_ipc::SizeChange;
 use smithay::backend::renderer::element::utils::{
     CropRenderElement, Relocate, RelocateRenderElement,
 };
-use smithay::backend::renderer::{ImportAll, Renderer};
-use smithay::desktop::Window;
 use smithay::output::Output;
 use smithay::utils::{Logical, Point, Rectangle, Scale};
 
 use super::workspace::{
-    compute_working_area, Column, ColumnWidth, OutputId, Workspace, WorkspaceRenderElement,
+    compute_working_area, Column, ColumnWidth, OutputId, Workspace, WorkspaceId,
+    WorkspaceRenderElement,
 };
 use super::{LayoutElement, Options};
 use crate::animation::Animation;
+use crate::render_helpers::renderer::NiriRenderer;
+use crate::render_helpers::RenderTarget;
+use crate::rubber_band::RubberBand;
+use crate::swipe_tracker::SwipeTracker;
 use crate::utils::output_size;
 
+/// Amount of touchpad movement to scroll the height of one workspace.
+const WORKSPACE_GESTURE_MOVEMENT: f64 = 300.;
+
+const WORKSPACE_GESTURE_RUBBER_BAND: RubberBand = RubberBand {
+    stiffness: 0.5,
+    limit: 0.05,
+};
+
 #[derive(Debug)]
 pub struct Monitor<W: LayoutElement> {
     /// Output for this monitor.
@@ -26,6 +37,8 @@ pub struct Monitor<W: LayoutElement> {
     pub workspaces: Vec<Workspace<W>>,
     /// Index of the currently active workspace.
     pub active_workspace_idx: usize,
+    /// ID of the previously active workspace.
+    pub previous_workspace_id: Option<WorkspaceId>,
     /// In-progress switch between workspaces.
     pub workspace_switch: Option<WorkspaceSwitch>,
     /// Configurable properties of the layout.
@@ -44,6 +57,7 @@ pub struct WorkspaceSwitchGesture {
     pub center_idx: usize,
     /// Current, fractional workspace index.
     pub current_idx: f64,
+    pub tracker: SwipeTracker,
 }
 
 pub type MonitorRenderElement<R> =
@@ -57,6 +71,13 @@ impl WorkspaceSwitch {
         }
     }
 
+    pub fn target_idx(&self) -> f64 {
+        match self {
+            WorkspaceSwitch::Animation(anim) => anim.to(),
+            WorkspaceSwitch::Gesture(gesture) => gesture.current_idx,
+        }
+    }
+
     /// Returns `true` if the workspace switch is [`Animation`].
     ///
     /// [`Animation`]: WorkspaceSwitch::Animation
@@ -72,11 +93,16 @@ impl<W: LayoutElement> Monitor<W> {
             output,
             workspaces,
             active_workspace_idx: 0,
+            previous_workspace_id: None,
             workspace_switch: None,
             options,
         }
     }
 
+    pub fn active_workspace_ref(&self) -> &Workspace<W> {
+        &self.workspaces[self.active_workspace_idx]
+    }
+
     pub fn active_workspace(&mut self) -> &mut Workspace<W> {
         &mut self.workspaces[self.active_workspace_idx]
     }
@@ -86,18 +112,22 @@ impl<W: LayoutElement> Monitor<W> {
             return;
         }
 
+        // FIXME: also compute and use current velocity.
         let current_idx = self
             .workspace_switch
             .as_ref()
             .map(|s| s.current_idx())
             .unwrap_or(self.active_workspace_idx as f64);
 
+        self.previous_workspace_id = Some(self.workspaces[self.active_workspace_idx].id());
+
         self.active_workspace_idx = idx;
 
         self.workspace_switch = Some(WorkspaceSwitch::Animation(Animation::new(
             current_idx,
             idx as f64,
-            Duration::from_millis(250),
+            0.,
+            self.options.animations.workspace_switch.0,
         )));
     }
 
@@ -127,6 +157,26 @@ impl<W: LayoutElement> Monitor<W> {
         }
     }
 
+    pub fn add_window_right_of(
+        &mut self,
+        right_of: &W::Id,
+        window: W,
+        width: ColumnWidth,
+        is_full_width: bool,
+    ) {
+        let workspace_idx = self
+            .workspaces
+            .iter_mut()
+            .position(|ws| ws.has_window(right_of))
+            .unwrap();
+        let workspace = &mut self.workspaces[workspace_idx];
+
+        workspace.add_window_right_of(right_of, window, width, is_full_width);
+
+        // After adding a new window, workspace becomes this output's own.
+        workspace.original_output = OutputId::new(&self.output);
+    }
+
     pub fn add_column(&mut self, workspace_idx: usize, column: Column<W>, activate: bool) {
         let workspace = &mut self.workspaces[workspace_idx];
 
@@ -216,6 +266,14 @@ impl<W: LayoutElement> Monitor<W> {
         }
     }
 
+    pub fn consume_or_expel_window_left(&mut self) {
+        self.active_workspace().consume_or_expel_window_left();
+    }
+
+    pub fn consume_or_expel_window_right(&mut self) {
+        self.active_workspace().consume_or_expel_window_right();
+    }
+
     pub fn focus_left(&mut self) {
         self.active_workspace().focus_left();
     }
@@ -287,8 +345,9 @@ impl<W: LayoutElement> Monitor<W> {
         let column = &workspace.columns[workspace.active_column_idx];
         let width = column.width;
         let is_full_width = column.is_full_width;
-        let window =
+        let window = workspace
-            workspace.remove_window_by_idx(workspace.active_column_idx, column.active_tile_idx);
+            .remove_tile_by_idx(workspace.active_column_idx, column.active_tile_idx, None)
+            .into_window();
 
         self.add_window(new_idx, window, true, width, is_full_width);
     }
@@ -309,8 +368,9 @@ impl<W: LayoutElement> Monitor<W> {
         let column = &workspace.columns[workspace.active_column_idx];
         let width = column.width;
         let is_full_width = column.is_full_width;
-        let window =
+        let window = workspace
-            workspace.remove_window_by_idx(workspace.active_column_idx, column.active_tile_idx);
+            .remove_tile_by_idx(workspace.active_column_idx, column.active_tile_idx, None)
+            .into_window();
 
         self.add_window(new_idx, window, true, width, is_full_width);
     }
@@ -331,8 +391,9 @@ impl<W: LayoutElement> Monitor<W> {
         let column = &workspace.columns[workspace.active_column_idx];
         let width = column.width;
         let is_full_width = column.is_full_width;
-        let window =
+        let window = workspace
-            workspace.remove_window_by_idx(workspace.active_column_idx, column.active_tile_idx);
+            .remove_tile_by_idx(workspace.active_column_idx, column.active_tile_idx, None)
+            .into_window();
 
         self.add_window(new_idx, window, true, width, is_full_width);
 
@@ -409,6 +470,11 @@ impl<W: LayoutElement> Monitor<W> {
         ));
     }
 
+    fn previous_workspace_idx(&self) -> Option<usize> {
+        let id = self.previous_workspace_id?;
+        self.workspaces.iter().position(|w| w.id() == id)
+    }
+
     pub fn switch_workspace(&mut self, idx: usize) {
         self.activate_workspace(min(idx, self.workspaces.len() - 1));
         // Don't animate this action.
@@ -417,6 +483,24 @@ impl<W: LayoutElement> Monitor<W> {
         self.clean_up_workspaces();
     }
 
+    pub fn switch_workspace_auto_back_and_forth(&mut self, idx: usize) {
+        let idx = min(idx, self.workspaces.len() - 1);
+
+        if idx == self.active_workspace_idx {
+            if let Some(prev_idx) = self.previous_workspace_idx() {
+                self.switch_workspace(prev_idx);
+            }
+        } else {
+            self.switch_workspace(idx);
+        }
+    }
+
+    pub fn switch_workspace_previous(&mut self) {
+        if let Some(idx) = self.previous_workspace_idx() {
+            self.switch_workspace(idx);
+        }
+    }
+
     pub fn consume_into_column(&mut self) {
         self.active_workspace().consume_into_column();
     }
@@ -462,7 +546,10 @@ impl<W: LayoutElement> Monitor<W> {
 
     pub fn are_transitions_ongoing(&self) -> bool {
         self.workspace_switch.is_some()
-            || self.workspaces.iter().any(|ws| ws.are_animations_ongoing())
+            || self
+                .workspaces
+                .iter()
+                .any(|ws| ws.are_transitions_ongoing())
     }
 
     pub fn update_config(&mut self, options: Rc<Options>) {
@@ -512,8 +599,10 @@ impl<W: LayoutElement> Monitor<W> {
             self.workspaces.push(ws);
         }
 
+        let previous_workspace_id = self.previous_workspace_id;
         self.activate_workspace(new_idx);
         self.workspace_switch = None;
+        self.previous_workspace_id = previous_workspace_id;
 
         self.clean_up_workspaces();
     }
@@ -532,12 +621,33 @@ impl<W: LayoutElement> Monitor<W> {
             self.workspaces.push(ws);
         }
 
+        let previous_workspace_id = self.previous_workspace_id;
         self.activate_workspace(new_idx);
         self.workspace_switch = None;
+        self.previous_workspace_id = previous_workspace_id;
 
         self.clean_up_workspaces();
     }
 
+    /// Returns the geometry of the active tile relative to and clamped to the output.
+    ///
+    /// During animations, assumes the final view position.
+    pub fn active_tile_visual_rectangle(&self) -> Option<Rectangle<i32, Logical>> {
+        let mut rect = self.active_workspace_ref().active_tile_visual_rectangle()?;
+
+        if let Some(switch) = &self.workspace_switch {
+            let size = output_size(&self.output);
+
+            let offset = switch.target_idx() - self.active_workspace_idx as f64;
+            let offset = (offset * size.h as f64).round() as i32;
+
+            let clip_rect = Rectangle::from_loc_and_size((0, -offset), size);
+            rect = rect.intersection(clip_rect)?;
+        }
+
+        Some(rect)
+    }
+
     pub fn window_under(
         &self,
         pos_within_output: Point<f64, Logical>,
@@ -547,14 +657,28 @@ impl<W: LayoutElement> Monitor<W> {
                 let size = output_size(&self.output);
 
                 let render_idx = switch.current_idx();
-                let before_idx = render_idx.floor() as usize;
+                let before_idx = render_idx.floor();
-                let after_idx = render_idx.ceil() as usize;
+                let after_idx = render_idx.ceil();
 
-                let offset = ((render_idx - before_idx as f64) * size.h as f64).round() as i32;
+                let offset = ((render_idx - before_idx) * size.h as f64).round() as i32;
+
+                if after_idx < 0. || before_idx as usize >= self.workspaces.len() {
+                    return None;
+                }
+
+                let after_idx = after_idx as usize;
 
                 let (idx, ws_offset) = if pos_within_output.y < (size.h - offset) as f64 {
-                    (before_idx, Point::from((0, offset)))
+                    if before_idx < 0. {
+                        return None;
+                    }
+
+                    (before_idx as usize, Point::from((0, offset)))
                 } else {
+                    if after_idx >= self.workspaces.len() {
+                        return None;
+                    }
+
                     (after_idx, Point::from((0, -size.h + offset)))
                 };
 
@@ -578,16 +702,12 @@ impl<W: LayoutElement> Monitor<W> {
         let ws = &self.workspaces[self.active_workspace_idx];
         ws.render_above_top_layer()
     }
-}
 
-impl Monitor<Window> {
+    pub fn render_elements<R: NiriRenderer>(
-    pub fn render_elements<R: Renderer + ImportAll>(
         &self,
         renderer: &mut R,
-    ) -> Vec<MonitorRenderElement<R>>
+        target: RenderTarget,
-    where
+    ) -> Vec<MonitorRenderElement<R>> {
-        <R as Renderer>::TextureId: 'static,
-    {
         let _span = tracy_client::span!("Monitor::render_elements");
 
         let output_scale = Scale::from(self.output.current_scale().fractional_scale());
@@ -598,40 +718,67 @@ impl Monitor<Window> {
         match &self.workspace_switch {
             Some(switch) => {
                 let render_idx = switch.current_idx();
-                let before_idx = render_idx.floor() as usize;
+                let before_idx = render_idx.floor();
-                let after_idx = render_idx.ceil() as usize;
+                let after_idx = render_idx.ceil();
 
-                let offset = ((render_idx - before_idx as f64) * size.h as f64).round() as i32;
+                let offset = ((render_idx - before_idx) * size.h as f64).round() as i32;
 
-                let before = self.workspaces[before_idx].render_elements(renderer);
+                if after_idx < 0. || before_idx as usize >= self.workspaces.len() {
-                let after = self.workspaces[after_idx].render_elements(renderer);
+                    return vec![];
+                }
 
+                let after_idx = after_idx as usize;
+                let after = if after_idx < self.workspaces.len() {
+                    let after = self.workspaces[after_idx].render_elements(renderer, target);
+                    let after = after.into_iter().filter_map(|elem| {
+                        Some(RelocateRenderElement::from_element(
+                            CropRenderElement::from_element(
+                                elem,
+                                output_scale,
+                                // HACK: crop to infinite bounds for all sides except the side
+                                // where the workspaces join,
+                                // otherwise it will cut pixel shaders and mess up
+                                // the coordinate space.
+                                Rectangle::from_extemities(
+                                    (-i32::MAX / 2, 0),
+                                    (i32::MAX / 2, i32::MAX / 2),
+                                ),
+                            )?,
+                            (0, -offset + size.h),
+                            Relocate::Relative,
+                        ))
+                    });
+
+                    if before_idx < 0. {
+                        return after.collect();
+                    }
+
+                    Some(after)
+                } else {
+                    None
+                };
+
+                let before_idx = before_idx as usize;
+                let before = self.workspaces[before_idx].render_elements(renderer, target);
                 let before = before.into_iter().filter_map(|elem| {
                     Some(RelocateRenderElement::from_element(
                         CropRenderElement::from_element(
                             elem,
                             output_scale,
-                            Rectangle::from_extemities((0, offset), (size.w, size.h)),
+                            Rectangle::from_extemities(
+                                (-i32::MAX / 2, -i32::MAX / 2),
+                                (i32::MAX / 2, size.h),
+                            ),
                         )?,
                         (0, -offset),
                         Relocate::Relative,
                     ))
                 });
-                let after = after.into_iter().filter_map(|elem| {
+                before.chain(after.into_iter().flatten()).collect()
-                    Some(RelocateRenderElement::from_element(
-                        CropRenderElement::from_element(
-                            elem,
-                            output_scale,
-                            Rectangle::from_extemities((0, 0), (size.w, offset)),
-                        )?,
-                        (0, -offset + size.h),
-                        Relocate::Relative,
-                    ))
-                });
-                before.chain(after).collect()
             }
             None => {
-                let elements = self.workspaces[self.active_workspace_idx].render_elements(renderer);
+                let elements =
+                    self.workspaces[self.active_workspace_idx].render_elements(renderer, target);
                 elements
                     .into_iter()
                     .filter_map(|elem| {
@@ -656,4 +803,87 @@ impl Monitor<Window> {
             }
         }
     }
+
+    pub fn workspace_switch_gesture_begin(&mut self) {
+        let center_idx = self.active_workspace_idx;
+        let current_idx = self
+            .workspace_switch
+            .as_ref()
+            .map(|s| s.current_idx())
+            .unwrap_or(center_idx as f64);
+
+        let gesture = WorkspaceSwitchGesture {
+            center_idx,
+            current_idx,
+            tracker: SwipeTracker::new(),
+        };
+        self.workspace_switch = Some(WorkspaceSwitch::Gesture(gesture));
+    }
+
+    pub fn workspace_switch_gesture_update(
+        &mut self,
+        delta_y: f64,
+        timestamp: Duration,
+    ) -> Option<bool> {
+        let Some(WorkspaceSwitch::Gesture(gesture)) = &mut self.workspace_switch else {
+            return None;
+        };
+
+        gesture.tracker.push(delta_y, timestamp);
+
+        let pos = gesture.tracker.pos() / WORKSPACE_GESTURE_MOVEMENT;
+
+        let min = gesture.center_idx.saturating_sub(1) as f64;
+        let max = (gesture.center_idx + 1).min(self.workspaces.len() - 1) as f64;
+        let new_idx = gesture.center_idx as f64 + pos;
+        let new_idx = WORKSPACE_GESTURE_RUBBER_BAND.clamp(min, max, new_idx);
+
+        if gesture.current_idx == new_idx {
+            return Some(false);
+        }
+
+        gesture.current_idx = new_idx;
+        Some(true)
+    }
+
+    pub fn workspace_switch_gesture_end(&mut self, cancelled: bool) -> bool {
+        let Some(WorkspaceSwitch::Gesture(gesture)) = &mut self.workspace_switch else {
+            return false;
+        };
+
+        if cancelled {
+            self.workspace_switch = None;
+            self.clean_up_workspaces();
+            return true;
+        }
+
+        let mut velocity = gesture.tracker.velocity() / WORKSPACE_GESTURE_MOVEMENT;
+        let current_pos = gesture.tracker.pos() / WORKSPACE_GESTURE_MOVEMENT;
+        let pos = gesture.tracker.projected_end_pos() / WORKSPACE_GESTURE_MOVEMENT;
+
+        let min = gesture.center_idx.saturating_sub(1) as f64;
+        let max = (gesture.center_idx + 1).min(self.workspaces.len() - 1) as f64;
+        let new_idx = gesture.center_idx as f64 + pos;
+
+        let new_idx = WORKSPACE_GESTURE_RUBBER_BAND.clamp(min, max, new_idx);
+        let new_idx = new_idx.round() as usize;
+
+        velocity *= WORKSPACE_GESTURE_RUBBER_BAND.clamp_derivative(
+            min,
+            max,
+            gesture.center_idx as f64 + current_pos,
+        );
+
+        self.previous_workspace_id = Some(self.workspaces[self.active_workspace_idx].id());
+
+        self.active_workspace_idx = new_idx;
+        self.workspace_switch = Some(WorkspaceSwitch::Animation(Animation::new(
+            gesture.current_idx,
+            new_idx as f64,
+            velocity,
+            self.options.animations.workspace_switch.0,
+        )));
+
+        true
+    }
 }

src/layout/tile.rs

@@ -2,15 +2,27 @@ use std::cmp::max;
 use std::rc::Rc;
 use std::time::Duration;
 
+use smithay::backend::allocator::Fourcc;
 use smithay::backend::renderer::element::solid::{SolidColorBuffer, SolidColorRenderElement};
-use smithay::backend::renderer::element::utils::{Relocate, RelocateRenderElement};
+use smithay::backend::renderer::element::utils::RescaleRenderElement;
-use smithay::backend::renderer::element::Kind;
+use smithay::backend::renderer::element::{Element, Kind};
-use smithay::backend::renderer::{ImportAll, Renderer};
+use smithay::backend::renderer::gles::GlesRenderer;
-use smithay::utils::{Logical, Point, Rectangle, Scale, Size};
+use smithay::utils::{Logical, Point, Rectangle, Scale, Size, Transform};
 
-use super::focus_ring::FocusRing;
+use super::focus_ring::{FocusRing, FocusRingRenderElement};
-use super::workspace::WorkspaceRenderElement;
+use super::{
-use super::{LayoutElement, Options};
+    LayoutElement, LayoutElementRenderElement, LayoutElementRenderSnapshot, Options,
+    RESIZE_ANIMATION_THRESHOLD,
+};
+use crate::animation::Animation;
+use crate::niri_render_elements;
+use crate::render_helpers::crossfade::CrossfadeRenderElement;
+use crate::render_helpers::offscreen::OffscreenRenderElement;
+use crate::render_helpers::primary_gpu_texture::PrimaryGpuTextureRenderElement;
+use crate::render_helpers::renderer::NiriRenderer;
+use crate::render_helpers::shaders::Shaders;
+use crate::render_helpers::snapshot::RenderSnapshot;
+use crate::render_helpers::{render_to_encompassing_texture, RenderTarget, ToRenderElement};
 
 /// Toplevel window with decorations.
 #[derive(Debug)]
@@ -21,6 +33,12 @@ pub struct Tile<W: LayoutElement> {
     /// The border around the window.
     border: FocusRing,
 
+    /// The focus ring around the window.
+    ///
+    /// It's supposed to be on the Workspace, but for the sake of a nicer open animation it's
+    /// currently here.
+    focus_ring: FocusRing,
+
     /// Whether this tile is fullscreen.
     ///
     /// This will update only when the `window` actually goes fullscreen, rather than right away,
@@ -33,24 +51,80 @@ pub struct Tile<W: LayoutElement> {
     /// The size we were requested to fullscreen into.
     fullscreen_size: Size<i32, Logical>,
 
+    /// The animation upon opening a window.
+    open_animation: Option<Animation>,
+
+    /// The animation of the window resizing.
+    resize_animation: Option<ResizeAnimation>,
+
+    /// The animation of a tile visually moving horizontally.
+    move_x_animation: Option<MoveAnimation>,
+
+    /// The animation of a tile visually moving vertically.
+    move_y_animation: Option<MoveAnimation>,
+
     /// Configurable properties of the layout.
-    options: Rc<Options>,
+    pub options: Rc<Options>,
+}
+
+niri_render_elements! {
+    TileRenderElement<R> => {
+        LayoutElement = LayoutElementRenderElement<R>,
+        FocusRing = FocusRingRenderElement,
+        SolidColor = SolidColorRenderElement,
+        Offscreen = RescaleRenderElement<OffscreenRenderElement>,
+        Crossfade = CrossfadeRenderElement,
+    }
+}
+
+niri_render_elements! {
+    TileSnapshotContentsRenderElement => {
+        Texture = PrimaryGpuTextureRenderElement,
+        SolidColor = SolidColorRenderElement,
+    }
+}
+
+niri_render_elements! {
+    TileSnapshotRenderElement => {
+        Contents = RescaleRenderElement<TileSnapshotContentsRenderElement>,
+        FocusRing = FocusRingRenderElement,
+        SolidColor = SolidColorRenderElement,
+    }
+}
+
+#[derive(Debug)]
+struct ResizeAnimation {
+    anim: Animation,
+    size_from: Size<i32, Logical>,
+    snapshot: LayoutElementRenderSnapshot,
+}
+
+#[derive(Debug)]
+struct MoveAnimation {
+    anim: Animation,
+    from: i32,
 }
 
 impl<W: LayoutElement> Tile<W> {
     pub fn new(window: W, options: Rc<Options>) -> Self {
         Self {
             window,
-            border: FocusRing::new(options.border),
+            border: FocusRing::new(options.border.into()),
+            focus_ring: FocusRing::new(options.focus_ring),
             is_fullscreen: false, // FIXME: up-to-date fullscreen right away, but we need size.
             fullscreen_backdrop: SolidColorBuffer::new((0, 0), [0., 0., 0., 1.]),
             fullscreen_size: Default::default(),
+            open_animation: None,
+            resize_animation: None,
+            move_x_animation: None,
+            move_y_animation: None,
             options,
         }
     }
 
     pub fn update_config(&mut self, options: Rc<Options>) {
-        self.border.update_config(options.border);
+        self.border.update_config(options.border.into());
+        self.focus_ring.update_config(options.focus_ring);
         self.options = options;
     }
 
@@ -59,26 +133,182 @@ impl<W: LayoutElement> Tile<W> {
         if self.fullscreen_size != Size::from((0, 0)) {
             self.is_fullscreen = self.window.is_fullscreen();
         }
+
+        if let Some(animate_from) = self.window.take_animation_snapshot() {
+            let size_from = if let Some(resize) = self.resize_animation.take() {
+                // Compute like in animated_window_size(), but using the snapshot geometry (since
+                // the current one is already overwritten).
+                let mut size = animate_from.size;
+
+                let val = resize.anim.value();
+                let size_from = resize.size_from;
+
+                size.w = (size_from.w as f64 + (size.w - size_from.w) as f64 * val).round() as i32;
+                size.h = (size_from.h as f64 + (size.h - size_from.h) as f64 * val).round() as i32;
+
+                size
+            } else {
+                animate_from.size
+            };
+
+            let change = self.window.size().to_point() - size_from.to_point();
+            let change = max(change.x.abs(), change.y.abs());
+            if change > RESIZE_ANIMATION_THRESHOLD {
+                let anim = Animation::new(0., 1., 0., self.options.animations.window_resize.0);
+                self.resize_animation = Some(ResizeAnimation {
+                    anim,
+                    size_from,
+                    snapshot: animate_from,
+                });
+            } else {
+                self.resize_animation = None;
+            }
+        }
     }
 
-    pub fn advance_animations(&mut self, _current_time: Duration, is_active: bool) {
+    pub fn advance_animations(&mut self, current_time: Duration, is_active: bool) {
-        let width = self.border.width();
+        if let Some(anim) = &mut self.open_animation {
-        self.border.update(
+            anim.set_current_time(current_time);
-            (width, width).into(),
+            if anim.is_done() {
-            self.window.size(),
+                self.open_animation = None;
-            self.window.has_ssd(),
+            }
-        );
+        }
+
+        if let Some(resize) = &mut self.resize_animation {
+            resize.anim.set_current_time(current_time);
+            if resize.anim.is_done() {
+                self.resize_animation = None;
+            }
+        }
+
+        if let Some(move_) = &mut self.move_x_animation {
+            move_.anim.set_current_time(current_time);
+            if move_.anim.is_done() {
+                self.move_x_animation = None;
+            }
+        }
+        if let Some(move_) = &mut self.move_y_animation {
+            move_.anim.set_current_time(current_time);
+            if move_.anim.is_done() {
+                self.move_y_animation = None;
+            }
+        }
+
+        let draw_border_with_background = self
+            .window
+            .rules()
+            .draw_border_with_background
+            .unwrap_or_else(|| !self.window.has_ssd());
+        self.border
+            .update(self.animated_window_size(), !draw_border_with_background);
         self.border.set_active(is_active);
+
+        let draw_focus_ring_with_background = if self.effective_border_width().is_some() {
+            false
+        } else {
+            draw_border_with_background
+        };
+        self.focus_ring
+            .update(self.animated_tile_size(), !draw_focus_ring_with_background);
+        self.focus_ring.set_active(is_active);
+    }
+
+    pub fn are_animations_ongoing(&self) -> bool {
+        self.open_animation.is_some()
+            || self.resize_animation.is_some()
+            || self.move_x_animation.is_some()
+            || self.move_y_animation.is_some()
+    }
+
+    pub fn render_offset(&self) -> Point<i32, Logical> {
+        let mut offset = Point::from((0., 0.));
+
+        if let Some(move_) = &self.move_x_animation {
+            offset.x += f64::from(move_.from) * move_.anim.value();
+        }
+        if let Some(move_) = &self.move_y_animation {
+            offset.y += f64::from(move_.from) * move_.anim.value();
+        }
+
+        offset.to_i32_round()
+    }
+
+    pub fn start_open_animation(&mut self) {
+        self.open_animation = Some(Animation::new(
+            0.,
+            1.,
+            0.,
+            self.options.animations.window_open.0,
+        ));
+    }
+
+    pub fn open_animation(&self) -> &Option<Animation> {
+        &self.open_animation
+    }
+
+    pub fn resize_animation(&self) -> Option<&Animation> {
+        self.resize_animation.as_ref().map(|resize| &resize.anim)
+    }
+
+    pub fn animate_move_from(&mut self, from: Point<i32, Logical>) {
+        self.animate_move_x_from(from.x);
+        self.animate_move_y_from(from.y);
+    }
+
+    pub fn animate_move_x_from(&mut self, from: i32) {
+        self.animate_move_x_from_with_config(from, self.options.animations.window_movement.0);
+    }
+
+    pub fn animate_move_x_from_with_config(&mut self, from: i32, config: niri_config::Animation) {
+        let current_offset = self.render_offset().x;
+
+        // Preserve the previous config if ongoing.
+        let anim = self.move_x_animation.take().map(|move_| move_.anim);
+        let anim = anim
+            .map(|anim| anim.restarted(1., 0., 0.))
+            .unwrap_or_else(|| Animation::new(1., 0., 0., config));
+
+        self.move_x_animation = Some(MoveAnimation {
+            anim,
+            from: from + current_offset,
+        });
+    }
+
+    pub fn animate_move_y_from(&mut self, from: i32) {
+        self.animate_move_y_from_with_config(from, self.options.animations.window_movement.0);
+    }
+
+    pub fn animate_move_y_from_with_config(&mut self, from: i32, config: niri_config::Animation) {
+        let current_offset = self.render_offset().y;
+
+        // Preserve the previous config if ongoing.
+        let anim = self.move_y_animation.take().map(|move_| move_.anim);
+        let anim = anim
+            .map(|anim| anim.restarted(1., 0., 0.))
+            .unwrap_or_else(|| Animation::new(1., 0., 0., config));
+
+        self.move_y_animation = Some(MoveAnimation {
+            anim,
+            from: from + current_offset,
+        });
     }
 
     pub fn window(&self) -> &W {
         &self.window
     }
 
+    pub fn window_mut(&mut self) -> &mut W {
+        &mut self.window
+    }
+
     pub fn into_window(self) -> W {
         self.window
     }
 
+    pub fn is_fullscreen(&self) -> bool {
+        self.is_fullscreen
+    }
+
     /// Returns `None` if the border is hidden and `Some(width)` if it should be shown.
     fn effective_border_width(&self) -> Option<i32> {
         if self.is_fullscreen {
@@ -141,6 +371,41 @@ impl<W: LayoutElement> Tile<W> {
         self.window.size()
     }
 
+    fn animated_window_size(&self) -> Size<i32, Logical> {
+        let mut size = self.window.size();
+
+        if let Some(resize) = &self.resize_animation {
+            let val = resize.anim.value();
+            let size_from = resize.size_from;
+
+            size.w = (size_from.w as f64 + (size.w - size_from.w) as f64 * val).round() as i32;
+            size.w = max(1, size.w);
+            size.h = (size_from.h as f64 + (size.h - size_from.h) as f64 * val).round() as i32;
+            size.h = max(1, size.h);
+        }
+
+        size
+    }
+
+    fn animated_tile_size(&self) -> Size<i32, Logical> {
+        let mut size = self.animated_window_size();
+
+        if self.is_fullscreen {
+            // Normally we'd just return the fullscreen size here, but this makes things a bit
+            // nicer if a fullscreen window is bigger than the fullscreen size for some reason.
+            size.w = max(size.w, self.fullscreen_size.w);
+            size.h = max(size.h, self.fullscreen_size.h);
+            return size;
+        }
+
+        if let Some(width) = self.effective_border_width() {
+            size.w = size.w.saturating_add(width * 2);
+            size.h = size.h.saturating_add(width * 2);
+        }
+
+        size
+    }
+
     pub fn buf_loc(&self) -> Point<i32, Logical> {
         let mut loc = Point::from((0, 0));
         loc += self.window_loc();
@@ -158,7 +423,7 @@ impl<W: LayoutElement> Tile<W> {
         activation_region.to_f64().contains(point)
     }
 
-    pub fn request_tile_size(&mut self, mut size: Size<i32, Logical>) {
+    pub fn request_tile_size(&mut self, mut size: Size<i32, Logical>, animate: bool) {
         // Can't go through effective_border_width() because we might be fullscreen.
         if !self.border.is_off() {
             let width = self.border.width();
@@ -166,7 +431,7 @@ impl<W: LayoutElement> Tile<W> {
             size.h = max(1, size.h - width * 2);
         }
 
-        self.window.request_size(size);
+        self.window.request_size(size, animate);
     }
 
     pub fn tile_width_for_window_width(&self, size: i32) -> i32 {
@@ -228,35 +493,226 @@ impl<W: LayoutElement> Tile<W> {
         size
     }
 
-    pub fn has_ssd(&self) -> bool {
+    pub fn draw_border_with_background(&self) -> bool {
-        self.effective_border_width().is_some() || self.window.has_ssd()
+        if self.effective_border_width().is_some() {
+            return false;
+        }
+
+        self.window
+            .rules()
+            .draw_border_with_background
+            .unwrap_or_else(|| !self.window.has_ssd())
     }
 
-    pub fn render<R: Renderer + ImportAll>(
+    fn render_inner<R: NiriRenderer>(
         &self,
         renderer: &mut R,
         location: Point<i32, Logical>,
         scale: Scale<f64>,
-    ) -> Vec<WorkspaceRenderElement<R>>
+        view_size: Size<i32, Logical>,
+        focus_ring: bool,
+        target: RenderTarget,
+    ) -> impl Iterator<Item = TileRenderElement<R>> {
+        let alpha = if self.is_fullscreen {
+            1.
+        } else {
+            self.window.rules().opacity.unwrap_or(1.).clamp(0., 1.)
+        };
+
+        let window_loc = self.window_loc();
+        let window_size = self.window_size();
+        let animated_window_size = self.animated_window_size();
+        let window_render_loc = location + window_loc;
+        let area = Rectangle::from_loc_and_size(window_render_loc, animated_window_size);
+
+        let gles_renderer = renderer.as_gles_renderer();
+
+        // If we're resizing, try to render a crossfade, or a fallback.
+        let mut crossfade = None;
+        let mut crossfade_fallback = None;
+
+        if let Some(resize) = &self.resize_animation {
+            if Shaders::get(gles_renderer).crossfade.is_some() {
+                if let Some(texture_from) = resize.snapshot.texture(gles_renderer, scale, target) {
+                    let window_elements =
+                        self.window
+                            .render(gles_renderer, Point::from((0, 0)), scale, 1., target);
+                    let current = render_to_encompassing_texture(
+                        gles_renderer,
+                        scale,
+                        Transform::Normal,
+                        Fourcc::Abgr8888,
+                        &window_elements,
+                    )
+                    .map_err(|err| warn!("error rendering window to texture: {err:?}"))
+                    .ok();
+
+                    if let Some((texture_current, _sync_point, texture_current_geo)) = current {
+                        let elem = CrossfadeRenderElement::new(
+                            gles_renderer,
+                            area,
+                            scale,
+                            texture_from.clone(),
+                            resize.snapshot.size,
+                            (texture_current, texture_current_geo),
+                            window_size,
+                            resize.anim.clamped_value().clamp(0., 1.) as f32,
+                            alpha,
+                        )
+                        .expect("we checked the crossfade shader above");
+                        self.window
+                            .set_offscreen_element_id(Some(elem.id().clone()));
+                        crossfade = Some(elem.into());
+                    }
+                }
+            }
+
+            if crossfade.is_none() {
+                let fallback_buffer = SolidColorBuffer::new(area.size, [1., 0., 0., 1.]);
+                crossfade_fallback = Some(
+                    SolidColorRenderElement::from_buffer(
+                        &fallback_buffer,
+                        area.loc.to_physical_precise_round(scale),
+                        scale,
+                        alpha,
+                        Kind::Unspecified,
+                    )
+                    .into(),
+                );
+                self.window.set_offscreen_element_id(None);
+            }
+        }
+
+        // If we're not resizing, render the window itself.
+        let mut window = None;
+        if crossfade.is_none() && crossfade_fallback.is_none() {
+            window = Some(
+                self.window
+                    .render(renderer, window_render_loc, scale, alpha, target)
+                    .into_iter()
+                    .map(Into::into),
+            );
+        }
+
+        let rv = crossfade
+            .into_iter()
+            .chain(crossfade_fallback)
+            .chain(window.into_iter().flatten());
+
+        let elem = self.effective_border_width().map(|width| {
+            self.border
+                .render(
+                    renderer,
+                    location + Point::from((width, width)),
+                    scale,
+                    view_size,
+                )
+                .map(Into::into)
+        });
+        let rv = rv.chain(elem.into_iter().flatten());
+
+        let elem = focus_ring.then(|| {
+            self.focus_ring
+                .render(renderer, location, scale, view_size)
+                .map(Into::into)
+        });
+        let rv = rv.chain(elem.into_iter().flatten());
+
+        let elem = self.is_fullscreen.then(|| {
+            SolidColorRenderElement::from_buffer(
+                &self.fullscreen_backdrop,
+                location.to_physical_precise_round(scale),
+                scale,
+                1.,
+                Kind::Unspecified,
+            )
+            .into()
+        });
+        rv.chain(elem)
+    }
+
+    pub fn render<R: NiriRenderer>(
+        &self,
+        renderer: &mut R,
+        location: Point<i32, Logical>,
+        scale: Scale<f64>,
+        view_size: Size<i32, Logical>,
+        focus_ring: bool,
+        target: RenderTarget,
+    ) -> impl Iterator<Item = TileRenderElement<R>> {
+        if let Some(anim) = &self.open_animation {
+            let renderer = renderer.as_gles_renderer();
+            let elements =
+                self.render_inner(renderer, location, scale, view_size, focus_ring, target);
+            let elements = elements.collect::<Vec<TileRenderElement<_>>>();
+
+            let elem = OffscreenRenderElement::new(
+                renderer,
+                scale.x as i32,
+                &elements,
+                anim.clamped_value().clamp(0., 1.) as f32,
+            );
+            self.window()
+                .set_offscreen_element_id(Some(elem.id().clone()));
+
+            let mut center = location;
+            center.x += self.tile_size().w / 2;
+            center.y += self.tile_size().h / 2;
+
+            Some(TileRenderElement::Offscreen(
+                RescaleRenderElement::from_element(
+                    elem,
+                    center.to_physical_precise_round(scale),
+                    (anim.value() / 2. + 0.5).max(0.),
+                ),
+            ))
+            .into_iter()
+            .chain(None.into_iter().flatten())
+        } else {
+            self.window().set_offscreen_element_id(None);
+
+            let elements =
+                self.render_inner(renderer, location, scale, view_size, focus_ring, target);
+            None.into_iter().chain(Some(elements).into_iter().flatten())
+        }
+    }
+
+    fn render_snapshot<E, C>(
+        &self,
+        renderer: &mut GlesRenderer,
+        scale: Scale<f64>,
+        view_size: Size<i32, Logical>,
+        contents: Vec<C>,
+    ) -> Vec<TileSnapshotRenderElement>
     where
-        <R as Renderer>::TextureId: 'static,
+        E: Into<TileSnapshotContentsRenderElement>,
+        C: ToRenderElement<RenderElement = E>,
     {
-        let mut rv = Vec::new();
+        let alpha = if self.is_fullscreen {
+            1.
+        } else {
+            self.window.rules().opacity.unwrap_or(1.).clamp(0., 1.)
+        };
 
-        let window_pos = location + self.window_loc();
+        let window_size = self.window_size();
-        rv.extend(self.window.render(renderer, window_pos, scale));
+        let animated_window_size = self.animated_window_size();
+        let animated_scale = animated_window_size.to_f64() / window_size.to_f64();
 
-        if self.effective_border_width().is_some() {
+        let mut rv = vec![];
+
+        for baked in contents {
+            let elem = baked.to_render_element(self.window_loc(), scale, alpha, Kind::Unspecified);
+            let elem: TileSnapshotContentsRenderElement = elem.into();
+
+            let origin = self.window_loc().to_physical_precise_round(scale);
+            let elem = RescaleRenderElement::from_element(elem, origin, animated_scale);
+            rv.push(elem.into());
+        }
+
+        if let Some(width) = self.effective_border_width() {
             rv.extend(
                 self.border
-                    .render(scale)
+                    .render(renderer, Point::from((width, width)), scale, view_size)
-                    .map(|elem| {
-                        RelocateRenderElement::from_element(
-                            elem,
-                            location.to_physical_precise_round(scale),
-                            Relocate::Relative,
-                        )
-                    })
                     .map(Into::into),
             );
         }
@@ -264,7 +720,7 @@ impl<W: LayoutElement> Tile<W> {
         if self.is_fullscreen {
             let elem = SolidColorRenderElement::from_buffer(
                 &self.fullscreen_backdrop,
-                location.to_physical_precise_round(scale),
+                Point::from((0, 0)),
                 scale,
                 1.,
                 Kind::Unspecified,
@@ -274,4 +730,27 @@ impl<W: LayoutElement> Tile<W> {
 
         rv
     }
+
+    pub fn take_snapshot_for_close_anim(
+        &self,
+        renderer: &mut GlesRenderer,
+        scale: Scale<f64>,
+        view_size: Size<i32, Logical>,
+    ) -> Option<RenderSnapshot<TileSnapshotRenderElement, TileSnapshotRenderElement>> {
+        let snapshot = self.window.take_unmap_snapshot()?;
+
+        Some(RenderSnapshot {
+            contents: self.render_snapshot(renderer, scale, view_size, snapshot.contents),
+            blocked_out_contents: self.render_snapshot(
+                renderer,
+                scale,
+                view_size,
+                snapshot.blocked_out_contents,
+            ),
+            block_out_from: snapshot.block_out_from,
+            size: self.animated_tile_size(),
+            texture: Default::default(),
+            blocked_out_texture: Default::default(),
+        })
+    }
 }

src/lib.rs

@@ -0,0 +1,31 @@
+#[macro_use]
+extern crate tracing;
+
+pub mod animation;
+pub mod backend;
+pub mod cli;
+pub mod cursor;
+#[cfg(feature = "dbus")]
+pub mod dbus;
+pub mod frame_clock;
+pub mod handlers;
+pub mod input;
+pub mod ipc;
+pub mod layout;
+pub mod niri;
+pub mod protocols;
+pub mod render_helpers;
+pub mod rubber_band;
+pub mod scroll_tracker;
+pub mod swipe_tracker;
+pub mod ui;
+pub mod utils;
+pub mod window;
+
+#[cfg(not(feature = "xdp-gnome-screencast"))]
+pub mod dummy_pw_utils;
+#[cfg(feature = "xdp-gnome-screencast")]
+pub mod pw_utils;
+
+#[cfg(not(feature = "xdp-gnome-screencast"))]
+pub use dummy_pw_utils as pw_utils;

src/main.rs

@@ -1,95 +1,33 @@
 #[macro_use]
 extern crate tracing;
 
-mod animation;
+use std::fmt::Write as _;
-mod backend;
+use std::fs::{self, File};
-mod config_error_notification;
+use std::io::{self, Write};
-mod cursor;
+use std::os::fd::FromRawFd;
-#[cfg(feature = "dbus")]
-mod dbus;
-mod exit_confirm_dialog;
-mod frame_clock;
-mod handlers;
-mod hotkey_overlay;
-mod input;
-mod ipc;
-mod layout;
-mod niri;
-mod render_helpers;
-mod screenshot_ui;
-mod utils;
-mod watcher;
-
-#[cfg(not(feature = "xdp-gnome-screencast"))]
-mod dummy_pw_utils;
-#[cfg(feature = "xdp-gnome-screencast")]
-mod pw_utils;
-
-use std::ffi::OsString;
 use std::path::PathBuf;
 use std::process::Command;
 use std::{env, mem};
 
-use clap::{Parser, Subcommand};
+use clap::Parser;
 use directories::ProjectDirs;
-#[cfg(not(feature = "xdp-gnome-screencast"))]
+use niri::animation;
-use dummy_pw_utils as pw_utils;
+use niri::cli::{Cli, Sub};
-use git_version::git_version;
+#[cfg(feature = "dbus")]
-use niri::{Niri, State};
+use niri::dbus;
+use niri::ipc::client::handle_msg;
+use niri::niri::State;
+use niri::utils::spawning::{
+    spawn, CHILD_ENV, REMOVE_ENV_RUST_BACKTRACE, REMOVE_ENV_RUST_LIB_BACKTRACE,
+};
+use niri::utils::watcher::Watcher;
+use niri::utils::{cause_panic, version, IS_SYSTEMD_SERVICE};
 use niri_config::Config;
 use portable_atomic::Ordering;
 use sd_notify::NotifyState;
-use smithay::reexports::calloop::{self, EventLoop};
+use smithay::reexports::calloop::EventLoop;
 use smithay::reexports::wayland_server::Display;
 use tracing_subscriber::EnvFilter;
-use utils::spawn;
-use watcher::Watcher;
-
-use crate::ipc::client::handle_msg;
-use crate::utils::{cause_panic, REMOVE_ENV_RUST_BACKTRACE, REMOVE_ENV_RUST_LIB_BACKTRACE};
-
-#[derive(Parser)]
-#[command(author, version = version(), about, long_about = None)]
-#[command(args_conflicts_with_subcommands = true)]
-#[command(subcommand_value_name = "SUBCOMMAND")]
-#[command(subcommand_help_heading = "Subcommands")]
-struct Cli {
-    /// Path to config file (default: `$XDG_CONFIG_HOME/niri/config.kdl`).
-    #[arg(short, long)]
-    config: Option<PathBuf>,
-    /// Command to run upon compositor startup.
-    #[arg(last = true)]
-    command: Vec<OsString>,
-
-    #[command(subcommand)]
-    subcommand: Option<Sub>,
-}
-
-#[derive(Subcommand)]
-enum Sub {
-    /// Validate the config file.
-    Validate {
-        /// Path to config file (default: `$XDG_CONFIG_HOME/niri/config.kdl`).
-        #[arg(short, long)]
-        config: Option<PathBuf>,
-    },
-    /// Communicate with the running niri instance.
-    Msg {
-        #[command(subcommand)]
-        msg: Msg,
-        /// Format output as JSON.
-        #[arg(short, long)]
-        json: bool,
-    },
-    /// Cause a panic to check if the backtraces are good.
-    Panic,
-}
-
-#[derive(Subcommand)]
-enum Msg {
-    /// List connected outputs.
-    Outputs,
-}
 
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     // Set backtrace defaults if not set.
@@ -102,7 +40,15 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         REMOVE_ENV_RUST_LIB_BACKTRACE.store(true, Ordering::Relaxed);
     }
 
-    let is_systemd_service = env::var_os("NOTIFY_SOCKET").is_some();
+    if env::var_os("NOTIFY_SOCKET").is_some() {
+        IS_SYSTEMD_SERVICE.store(true, Ordering::Relaxed);
+
+        #[cfg(not(feature = "systemd"))]
+        warn!(
+            "running as a systemd service, but systemd support is compiled out. \
+             Are you sure you did not forget to set `--features systemd`?"
+        );
+    }
 
     let directives = env::var("RUST_LOG").unwrap_or_else(|_| "niri=debug".to_owned());
     let env_filter = EnvFilter::builder().parse_lossy(directives);
@@ -111,21 +57,26 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         .with_env_filter(env_filter)
         .init();
 
-    if is_systemd_service {
+    let cli = Cli::parse();
-        // If we're starting as a systemd service, assume that the intention is to start on a TTY.
+
-        // Remove DISPLAY or WAYLAND_DISPLAY from our environment if they are set, since they will
+    if cli.session {
-        // cause the winit backend to be selected instead.
+        // If we're starting as a session, assume that the intention is to start on a TTY. Remove
+        // DISPLAY or WAYLAND_DISPLAY from our environment if they are set, since they will cause
+        // the winit backend to be selected instead.
         if env::var_os("DISPLAY").is_some() {
-            debug!("we're running as a systemd service but DISPLAY is set, removing it");
+            warn!("running as a session but DISPLAY is set, removing it");
             env::remove_var("DISPLAY");
         }
         if env::var_os("WAYLAND_DISPLAY").is_some() {
-            debug!("we're running as a systemd service but WAYLAND_DISPLAY is set, removing it");
+            warn!("running as a session but WAYLAND_DISPLAY is set, removing it");
             env::remove_var("WAYLAND_DISPLAY");
         }
-    }
 
-    let cli = Cli::parse();
+        // Set the current desktop for xdg-desktop-portal.
+        env::set_var("XDG_CURRENT_DESKTOP", "niri");
+        // Ensure the session type is set to Wayland for xdg-autostart and Qt apps.
+        env::set_var("XDG_SESSION_TYPE", "wayland");
+    }
 
     let _client = tracy_client::Client::start();
 
@@ -154,7 +105,44 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     info!("starting version {}", &version());
 
     // Load the config.
-    let path = cli.config.or_else(default_config_path);
+    let mut config_created = false;
+    let path = cli.config.or_else(|| {
+        let default_path = default_config_path()?;
+        let default_parent = default_path.parent().unwrap();
+
+        if let Err(err) = fs::create_dir_all(default_parent) {
+            warn!(
+                "error creating config directories {:?}: {err:?}",
+                default_parent
+            );
+            return Some(default_path);
+        }
+
+        // Create the config and fill it with the default config if it doesn't exist.
+        let new_file = File::options()
+            .read(true)
+            .write(true)
+            .create_new(true)
+            .open(&default_path);
+        match new_file {
+            Ok(mut new_file) => {
+                let default = include_bytes!("../resources/default-config.kdl");
+                match new_file.write_all(default) {
+                    Ok(()) => {
+                        config_created = true;
+                        info!("wrote default config to {:?}", &default_path);
+                    }
+                    Err(err) => {
+                        warn!("error writing config file at {:?}: {err:?}", &default_path)
+                    }
+                }
+            }
+            Err(err) if err.kind() == io::ErrorKind::AlreadyExists => {}
+            Err(err) => warn!("error creating config file at {:?}: {err:?}", &default_path),
+        }
+
+        Some(default_path)
+    });
 
     let mut config_errored = false;
     let mut config = path
@@ -169,8 +157,15 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         })
         .unwrap_or_default();
 
-    animation::ANIMATION_SLOWDOWN.store(config.debug.animation_slowdown, Ordering::Relaxed);
+    let slowdown = if config.animations.off {
+        0.
+    } else {
+        config.animations.slowdown.clamp(0., 100.)
+    };
+    animation::ANIMATION_SLOWDOWN.store(slowdown, Ordering::Relaxed);
+
     let spawn_at_startup = mem::take(&mut config.spawn_at_startup);
+    *CHILD_ENV.write().unwrap() = mem::take(&mut config.environment);
 
     // Create the compositor.
     let mut event_loop = EventLoop::try_new().unwrap();
@@ -180,7 +175,8 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         event_loop.handle(),
         event_loop.get_signal(),
         display,
-    );
+    )
+    .unwrap();
 
     // Set WAYLAND_DISPLAY for children.
     let socket_name = &state.niri.socket_name;
@@ -196,9 +192,9 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         info!("IPC listening on: {}", ipc.socket_path.to_string_lossy());
     }
 
-    if is_systemd_service {
+    if cli.session {
-        // We're starting as a systemd service. Export our variables.
+        // We're starting as a session. Import our variables.
-        import_env_to_systemd();
+        import_environment();
 
         // Inhibit power key handling so we can suspend on it.
         #[cfg(feature = "dbus")]
@@ -210,15 +206,20 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     }
 
     #[cfg(feature = "dbus")]
-    dbus::DBusServers::start(&mut state, is_systemd_service);
+    dbus::DBusServers::start(&mut state, cli.session);
 
     // Notify systemd we're ready.
     if let Err(err) = sd_notify::notify(true, &[NotifyState::Ready]) {
         warn!("error notifying systemd: {err:?}");
     };
 
+    // Send ready notification to the NOTIFY_FD file descriptor.
+    if let Err(err) = notify_fd() {
+        warn!("error notifying fd: {err:?}");
+    }
+
     // Set up config file watcher.
-    let _watcher = if let Some(path) = path {
+    let _watcher = if let Some(path) = path.clone() {
         let (tx, rx) = calloop::channel::sync_channel(1);
         let watcher = Watcher::new(path.clone(), tx);
         event_loop
@@ -243,6 +244,8 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     // Show the config error notification right away if needed.
     if config_errored {
         state.niri.config_error_notification.show();
+    } else if config_created {
+        state.niri.config_error_notification.show_created(path);
     }
 
     // Run the compositor.
@@ -253,21 +256,35 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     Ok(())
 }
 
-fn version() -> String {
+fn import_environment() {
-    format!(
+    let variables = [
-        "{} ({})",
+        "WAYLAND_DISPLAY",
-        env!("CARGO_PKG_VERSION"),
+        "XDG_CURRENT_DESKTOP",
-        git_version!(fallback = "unknown commit"),
+        "XDG_SESSION_TYPE",
-    )
+        niri_ipc::SOCKET_PATH_ENV,
-}
+    ]
+    .join(" ");
+
+    let mut init_system_import = String::new();
+    if cfg!(feature = "systemd") {
+        write!(
+            init_system_import,
+            "systemctl --user import-environment {variables};"
+        )
+        .unwrap();
+    }
+    if cfg!(feature = "dinit") {
+        write!(init_system_import, "dinitctl setenv {variables};").unwrap();
+    }
 
-fn import_env_to_systemd() {
     let rv = Command::new("/bin/sh")
         .args([
             "-c",
-            "systemctl --user import-environment WAYLAND_DISPLAY && \
+            &format!(
-             hash dbus-update-activation-environment 2>/dev/null && \
+                "{init_system_import}\
-             dbus-update-activation-environment WAYLAND_DISPLAY",
+                 hash dbus-update-activation-environment 2>/dev/null && \
+                 dbus-update-activation-environment {variables}"
+            ),
         ])
         .spawn();
     // Wait for the import process to complete, otherwise services will start too fast without
@@ -284,7 +301,7 @@ fn import_env_to_systemd() {
             }
         },
         Err(err) => {
-            warn!("error spawning shell to import environment into systemd: {err:?}");
+            warn!("error spawning shell to import environment: {err:?}");
         }
     }
 }
@@ -299,3 +316,15 @@ fn default_config_path() -> Option<PathBuf> {
     path.push("config.kdl");
     Some(path)
 }
+
+fn notify_fd() -> anyhow::Result<()> {
+    let fd = match env::var("NOTIFY_FD") {
+        Ok(notify_fd) => notify_fd.parse()?,
+        Err(env::VarError::NotPresent) => return Ok(()),
+        Err(err) => return Err(err.into()),
+    };
+    env::remove_var("NOTIFY_FD");
+    let mut notif = unsafe { File::from_raw_fd(fd) };
+    notif.write_all(b"READY=1\n")?;
+    Ok(())
+}

src/protocols/foreign_toplevel.rs

@@ -0,0 +1,466 @@
+use std::collections::hash_map::Entry;
+use std::collections::HashMap;
+
+use arrayvec::ArrayVec;
+use smithay::output::Output;
+use smithay::reexports::wayland_protocols::xdg::shell::server::xdg_toplevel;
+use smithay::reexports::wayland_protocols_wlr;
+use smithay::reexports::wayland_server::backend::ClientId;
+use smithay::reexports::wayland_server::protocol::wl_output::WlOutput;
+use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
+use smithay::reexports::wayland_server::{
+    Client, DataInit, Dispatch, DisplayHandle, GlobalDispatch, New, Resource,
+};
+use smithay::wayland::compositor::with_states;
+use smithay::wayland::shell::xdg::{
+    ToplevelStateSet, XdgToplevelSurfaceData, XdgToplevelSurfaceRoleAttributes,
+};
+use wayland_protocols_wlr::foreign_toplevel::v1::server::{
+    zwlr_foreign_toplevel_handle_v1, zwlr_foreign_toplevel_manager_v1,
+};
+use zwlr_foreign_toplevel_handle_v1::ZwlrForeignToplevelHandleV1;
+use zwlr_foreign_toplevel_manager_v1::ZwlrForeignToplevelManagerV1;
+
+use crate::niri::State;
+
+const VERSION: u32 = 3;
+
+pub struct ForeignToplevelManagerState {
+    display: DisplayHandle,
+    instances: Vec<ZwlrForeignToplevelManagerV1>,
+    toplevels: HashMap<WlSurface, ToplevelData>,
+}
+
+pub trait ForeignToplevelHandler {
+    fn foreign_toplevel_manager_state(&mut self) -> &mut ForeignToplevelManagerState;
+    fn activate(&mut self, wl_surface: WlSurface);
+    fn close(&mut self, wl_surface: WlSurface);
+    fn set_fullscreen(&mut self, wl_surface: WlSurface, wl_output: Option<WlOutput>);
+    fn unset_fullscreen(&mut self, wl_surface: WlSurface);
+}
+
+struct ToplevelData {
+    title: Option<String>,
+    app_id: Option<String>,
+    states: ArrayVec<u32, 3>,
+    output: Option<Output>,
+    instances: HashMap<ZwlrForeignToplevelHandleV1, Vec<WlOutput>>,
+    // FIXME: parent.
+}
+
+pub struct ForeignToplevelGlobalData {
+    filter: Box<dyn for<'c> Fn(&'c Client) -> bool + Send + Sync>,
+}
+
+impl ForeignToplevelManagerState {
+    pub fn new<D, F>(display: &DisplayHandle, filter: F) -> Self
+    where
+        D: GlobalDispatch<ZwlrForeignToplevelManagerV1, ForeignToplevelGlobalData>,
+        D: Dispatch<ZwlrForeignToplevelManagerV1, ()>,
+        D: 'static,
+        F: for<'c> Fn(&'c Client) -> bool + Send + Sync + 'static,
+    {
+        let global_data = ForeignToplevelGlobalData {
+            filter: Box::new(filter),
+        };
+        display.create_global::<D, ZwlrForeignToplevelManagerV1, _>(VERSION, global_data);
+        Self {
+            display: display.clone(),
+            instances: Vec::new(),
+            toplevels: HashMap::new(),
+        }
+    }
+}
+
+pub fn refresh(state: &mut State) {
+    let _span = tracy_client::span!("foreign_toplevel::refresh");
+
+    let protocol_state = &mut state.niri.foreign_toplevel_state;
+
+    // Handle closed windows.
+    protocol_state.toplevels.retain(|surface, data| {
+        if state.niri.layout.find_window_and_output(surface).is_some() {
+            return true;
+        }
+
+        for instance in data.instances.keys() {
+            instance.closed();
+        }
+
+        false
+    });
+
+    // Handle new and existing windows.
+    //
+    // Save the focused window for last, this way when the focus changes, we will first deactivate
+    // the previous window and only then activate the newly focused window.
+    let mut focused = None;
+    state.niri.layout.with_windows(|mapped, output| {
+        let wl_surface = mapped.toplevel().wl_surface();
+
+        with_states(wl_surface, |states| {
+            let role = states
+                .data_map
+                .get::<XdgToplevelSurfaceData>()
+                .unwrap()
+                .lock()
+                .unwrap();
+
+            if state.niri.keyboard_focus.surface() == Some(wl_surface) {
+                focused = Some((mapped.window.clone(), output.cloned()));
+            } else {
+                refresh_toplevel(protocol_state, wl_surface, &role, output, false);
+            }
+        });
+    });
+
+    // Finally, refresh the focused window.
+    if let Some((window, output)) = focused {
+        let wl_surface = window.toplevel().expect("no x11 support").wl_surface();
+
+        with_states(wl_surface, |states| {
+            let role = states
+                .data_map
+                .get::<XdgToplevelSurfaceData>()
+                .unwrap()
+                .lock()
+                .unwrap();
+
+            refresh_toplevel(protocol_state, wl_surface, &role, output.as_ref(), true);
+        });
+    }
+}
+
+pub fn on_output_bound(state: &mut State, output: &Output, wl_output: &WlOutput) {
+    let _span = tracy_client::span!("foreign_toplevel::on_output_bound");
+
+    let Some(client) = wl_output.client() else {
+        return;
+    };
+
+    let protocol_state = &mut state.niri.foreign_toplevel_state;
+    for data in protocol_state.toplevels.values_mut() {
+        if data.output.as_ref() != Some(output) {
+            continue;
+        }
+
+        for (instance, outputs) in &mut data.instances {
+            if instance.client().as_ref() != Some(&client) {
+                continue;
+            }
+
+            instance.output_enter(wl_output);
+            instance.done();
+            outputs.push(wl_output.clone());
+        }
+    }
+}
+
+fn refresh_toplevel(
+    protocol_state: &mut ForeignToplevelManagerState,
+    wl_surface: &WlSurface,
+    role: &XdgToplevelSurfaceRoleAttributes,
+    output: Option<&Output>,
+    has_focus: bool,
+) {
+    let states = to_state_vec(&role.current.states, has_focus);
+
+    match protocol_state.toplevels.entry(wl_surface.clone()) {
+        Entry::Occupied(entry) => {
+            // Existing window, check if anything changed.
+            let data = entry.into_mut();
+
+            let mut new_title = None;
+            if data.title != role.title {
+                data.title.clone_from(&role.title);
+                new_title = role.title.as_deref();
+
+                if new_title.is_none() {
+                    error!("toplevel title changed to None");
+                }
+            }
+
+            let mut new_app_id = None;
+            if data.app_id != role.app_id {
+                data.app_id.clone_from(&role.app_id);
+                new_app_id = role.app_id.as_deref();
+
+                if new_app_id.is_none() {
+                    error!("toplevel app_id changed to None");
+                }
+            }
+
+            let mut states_changed = false;
+            if data.states != states {
+                data.states = states;
+                states_changed = true;
+            }
+
+            let mut output_changed = false;
+            if data.output.as_ref() != output {
+                data.output = output.cloned();
+                output_changed = true;
+            }
+
+            let something_changed =
+                new_title.is_some() || new_app_id.is_some() || states_changed || output_changed;
+
+            if something_changed {
+                for (instance, outputs) in &mut data.instances {
+                    if let Some(new_title) = new_title {
+                        instance.title(new_title.to_owned());
+                    }
+                    if let Some(new_app_id) = new_app_id {
+                        instance.app_id(new_app_id.to_owned());
+                    }
+                    if states_changed {
+                        instance.state(data.states.iter().flat_map(|x| x.to_ne_bytes()).collect());
+                    }
+                    if output_changed {
+                        for wl_output in outputs.drain(..) {
+                            instance.output_leave(&wl_output);
+                        }
+                        if let Some(output) = &data.output {
+                            if let Some(client) = instance.client() {
+                                for wl_output in output.client_outputs(&client) {
+                                    instance.output_enter(&wl_output);
+                                    outputs.push(wl_output);
+                                }
+                            }
+                        }
+                    }
+                    instance.done();
+                }
+            }
+
+            for outputs in data.instances.values_mut() {
+                // Clean up dead wl_outputs.
+                outputs.retain(|x| x.is_alive());
+            }
+        }
+        Entry::Vacant(entry) => {
+            // New window, start tracking it.
+            let mut data = ToplevelData {
+                title: role.title.clone(),
+                app_id: role.app_id.clone(),
+                states,
+                output: output.cloned(),
+                instances: HashMap::new(),
+            };
+
+            for manager in &protocol_state.instances {
+                if let Some(client) = manager.client() {
+                    data.add_instance::<State>(&protocol_state.display, &client, manager);
+                }
+            }
+
+            entry.insert(data);
+        }
+    }
+}
+
+impl ToplevelData {
+    fn add_instance<D>(
+        &mut self,
+        handle: &DisplayHandle,
+        client: &Client,
+        manager: &ZwlrForeignToplevelManagerV1,
+    ) where
+        D: Dispatch<ZwlrForeignToplevelHandleV1, ()>,
+        D: 'static,
+    {
+        let toplevel = client
+            .create_resource::<ZwlrForeignToplevelHandleV1, _, D>(handle, manager.version(), ())
+            .unwrap();
+        manager.toplevel(&toplevel);
+
+        if let Some(title) = &self.title {
+            toplevel.title(title.clone());
+        }
+        if let Some(app_id) = &self.app_id {
+            toplevel.app_id(app_id.clone());
+        }
+
+        toplevel.state(self.states.iter().flat_map(|x| x.to_ne_bytes()).collect());
+
+        let mut outputs = Vec::new();
+        if let Some(output) = &self.output {
+            for wl_output in output.client_outputs(client) {
+                toplevel.output_enter(&wl_output);
+                outputs.push(wl_output);
+            }
+        }
+
+        toplevel.done();
+
+        self.instances.insert(toplevel, outputs);
+    }
+}
+
+impl<D> GlobalDispatch<ZwlrForeignToplevelManagerV1, ForeignToplevelGlobalData, D>
+    for ForeignToplevelManagerState
+where
+    D: GlobalDispatch<ZwlrForeignToplevelManagerV1, ForeignToplevelGlobalData>,
+    D: Dispatch<ZwlrForeignToplevelManagerV1, ()>,
+    D: Dispatch<ZwlrForeignToplevelHandleV1, ()>,
+    D: ForeignToplevelHandler,
+{
+    fn bind(
+        state: &mut D,
+        handle: &DisplayHandle,
+        client: &Client,
+        resource: New<ZwlrForeignToplevelManagerV1>,
+        _global_data: &ForeignToplevelGlobalData,
+        data_init: &mut DataInit<'_, D>,
+    ) {
+        let manager = data_init.init(resource, ());
+
+        let state = state.foreign_toplevel_manager_state();
+
+        for data in state.toplevels.values_mut() {
+            data.add_instance::<D>(handle, client, &manager);
+        }
+
+        state.instances.push(manager);
+    }
+
+    fn can_view(client: Client, global_data: &ForeignToplevelGlobalData) -> bool {
+        (global_data.filter)(&client)
+    }
+}
+
+impl<D> Dispatch<ZwlrForeignToplevelManagerV1, (), D> for ForeignToplevelManagerState
+where
+    D: Dispatch<ZwlrForeignToplevelManagerV1, ()>,
+    D: ForeignToplevelHandler,
+{
+    fn request(
+        state: &mut D,
+        _client: &Client,
+        resource: &ZwlrForeignToplevelManagerV1,
+        request: <ZwlrForeignToplevelManagerV1 as Resource>::Request,
+        _data: &(),
+        _dhandle: &DisplayHandle,
+        _data_init: &mut DataInit<'_, D>,
+    ) {
+        match request {
+            zwlr_foreign_toplevel_manager_v1::Request::Stop => {
+                resource.finished();
+
+                let state = state.foreign_toplevel_manager_state();
+                state.instances.retain(|x| x != resource);
+            }
+            _ => unreachable!(),
+        }
+    }
+
+    fn destroyed(
+        state: &mut D,
+        _client: ClientId,
+        resource: &ZwlrForeignToplevelManagerV1,
+        _data: &(),
+    ) {
+        let state = state.foreign_toplevel_manager_state();
+        state.instances.retain(|x| x != resource);
+    }
+}
+
+impl<D> Dispatch<ZwlrForeignToplevelHandleV1, (), D> for ForeignToplevelManagerState
+where
+    D: Dispatch<ZwlrForeignToplevelHandleV1, ()>,
+    D: ForeignToplevelHandler,
+{
+    fn request(
+        state: &mut D,
+        _client: &Client,
+        resource: &ZwlrForeignToplevelHandleV1,
+        request: <ZwlrForeignToplevelHandleV1 as Resource>::Request,
+        _data: &(),
+        _dhandle: &DisplayHandle,
+        _data_init: &mut DataInit<'_, D>,
+    ) {
+        let protocol_state = state.foreign_toplevel_manager_state();
+
+        let Some((surface, _)) = protocol_state
+            .toplevels
+            .iter()
+            .find(|(_, data)| data.instances.contains_key(resource))
+        else {
+            return;
+        };
+        let surface = surface.clone();
+
+        match request {
+            zwlr_foreign_toplevel_handle_v1::Request::SetMaximized => (),
+            zwlr_foreign_toplevel_handle_v1::Request::UnsetMaximized => (),
+            zwlr_foreign_toplevel_handle_v1::Request::SetMinimized => (),
+            zwlr_foreign_toplevel_handle_v1::Request::UnsetMinimized => (),
+            zwlr_foreign_toplevel_handle_v1::Request::Activate { .. } => {
+                state.activate(surface);
+            }
+            zwlr_foreign_toplevel_handle_v1::Request::Close => {
+                state.close(surface);
+            }
+            zwlr_foreign_toplevel_handle_v1::Request::SetRectangle { .. } => (),
+            zwlr_foreign_toplevel_handle_v1::Request::Destroy => (),
+            zwlr_foreign_toplevel_handle_v1::Request::SetFullscreen { output } => {
+                state.set_fullscreen(surface, output);
+            }
+            zwlr_foreign_toplevel_handle_v1::Request::UnsetFullscreen => {
+                state.unset_fullscreen(surface);
+            }
+            _ => unreachable!(),
+        }
+    }
+
+    fn destroyed(
+        state: &mut D,
+        _client: ClientId,
+        resource: &ZwlrForeignToplevelHandleV1,
+        _data: &(),
+    ) {
+        let state = state.foreign_toplevel_manager_state();
+        for data in state.toplevels.values_mut() {
+            data.instances.retain(|instance, _| instance != resource);
+        }
+    }
+}
+
+fn to_state_vec(states: &ToplevelStateSet, has_focus: bool) -> ArrayVec<u32, 3> {
+    let mut rv = ArrayVec::new();
+    if states.contains(xdg_toplevel::State::Maximized) {
+        rv.push(zwlr_foreign_toplevel_handle_v1::State::Maximized as u32);
+    }
+    if states.contains(xdg_toplevel::State::Fullscreen) {
+        rv.push(zwlr_foreign_toplevel_handle_v1::State::Fullscreen as u32);
+    }
+
+    // HACK: wlr-foreign-toplevel-management states:
+    //
+    // These have the same meaning as the states with the same names defined in xdg-toplevel
+    //
+    // However, clients such as sfwbar and fcitx seem to treat the activated state as keyboard
+    // focus, i.e. they don't expect multiple windows to have it set at once. Even Waybar which
+    // handles multiple activated windows correctly uses it in its design in such a way that
+    // keyboard focus would make more sense. Let's do what the clients expect.
+    if has_focus {
+        rv.push(zwlr_foreign_toplevel_handle_v1::State::Activated as u32);
+    }
+
+    rv
+}
+
+#[macro_export]
+macro_rules! delegate_foreign_toplevel {
+    ($(@<$( $lt:tt $( : $clt:tt $(+ $dlt:tt )* )? ),+>)? $ty: ty) => {
+        smithay::reexports::wayland_server::delegate_global_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            smithay::reexports::wayland_protocols_wlr::foreign_toplevel::v1::server::zwlr_foreign_toplevel_manager_v1::ZwlrForeignToplevelManagerV1: $crate::protocols::foreign_toplevel::ForeignToplevelGlobalData
+        ] => $crate::protocols::foreign_toplevel::ForeignToplevelManagerState);
+        smithay::reexports::wayland_server::delegate_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            smithay::reexports::wayland_protocols_wlr::foreign_toplevel::v1::server::zwlr_foreign_toplevel_manager_v1::ZwlrForeignToplevelManagerV1: ()
+        ] => $crate::protocols::foreign_toplevel::ForeignToplevelManagerState);
+        smithay::reexports::wayland_server::delegate_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            smithay::reexports::wayland_protocols_wlr::foreign_toplevel::v1::server::zwlr_foreign_toplevel_handle_v1::ZwlrForeignToplevelHandleV1: ()
+        ] => $crate::protocols::foreign_toplevel::ForeignToplevelManagerState);
+    };
+}

src/protocols/gamma_control.rs

@@ -0,0 +1,246 @@
+use std::collections::HashMap;
+use std::fs::File;
+use std::io::Read;
+
+use smithay::output::Output;
+use smithay::reexports::wayland_protocols_wlr;
+use smithay::reexports::wayland_server::backend::ClientId;
+use smithay::reexports::wayland_server::{
+    Client, DataInit, Dispatch, DisplayHandle, GlobalDispatch, New, Resource,
+};
+use wayland_protocols_wlr::gamma_control::v1::server::{
+    zwlr_gamma_control_manager_v1, zwlr_gamma_control_v1,
+};
+use zwlr_gamma_control_manager_v1::ZwlrGammaControlManagerV1;
+use zwlr_gamma_control_v1::ZwlrGammaControlV1;
+
+const VERSION: u32 = 1;
+
+pub struct GammaControlManagerState {
+    // Active gamma controls only. Failed ones are removed.
+    gamma_controls: HashMap<Output, ZwlrGammaControlV1>,
+}
+
+pub struct GammaControlManagerGlobalData {
+    filter: Box<dyn for<'c> Fn(&'c Client) -> bool + Send + Sync>,
+}
+
+pub trait GammaControlHandler {
+    fn gamma_control_manager_state(&mut self) -> &mut GammaControlManagerState;
+    fn get_gamma_size(&mut self, output: &Output) -> Option<u32>;
+    fn set_gamma(&mut self, output: &Output, ramp: Option<Vec<u16>>) -> Option<()>;
+}
+
+pub struct GammaControlState {
+    gamma_size: u32,
+}
+
+impl GammaControlManagerState {
+    pub fn new<D, F>(display: &DisplayHandle, filter: F) -> Self
+    where
+        D: GlobalDispatch<ZwlrGammaControlManagerV1, GammaControlManagerGlobalData>,
+        D: Dispatch<ZwlrGammaControlManagerV1, ()>,
+        D: Dispatch<ZwlrGammaControlV1, GammaControlState>,
+        D: GammaControlHandler,
+        D: 'static,
+        F: for<'c> Fn(&'c Client) -> bool + Send + Sync + 'static,
+    {
+        let global_data = GammaControlManagerGlobalData {
+            filter: Box::new(filter),
+        };
+        display.create_global::<D, ZwlrGammaControlManagerV1, _>(VERSION, global_data);
+
+        Self {
+            gamma_controls: HashMap::new(),
+        }
+    }
+
+    pub fn output_removed(&mut self, output: &Output) {
+        if let Some(gamma_control) = self.gamma_controls.remove(output) {
+            gamma_control.failed();
+        }
+    }
+}
+
+impl<D> GlobalDispatch<ZwlrGammaControlManagerV1, GammaControlManagerGlobalData, D>
+    for GammaControlManagerState
+where
+    D: GlobalDispatch<ZwlrGammaControlManagerV1, GammaControlManagerGlobalData>,
+    D: Dispatch<ZwlrGammaControlManagerV1, ()>,
+    D: Dispatch<ZwlrGammaControlV1, GammaControlState>,
+    D: GammaControlHandler,
+    D: 'static,
+{
+    fn bind(
+        _state: &mut D,
+        _handle: &DisplayHandle,
+        _client: &Client,
+        manager: New<ZwlrGammaControlManagerV1>,
+        _manager_state: &GammaControlManagerGlobalData,
+        data_init: &mut DataInit<'_, D>,
+    ) {
+        data_init.init(manager, ());
+    }
+
+    fn can_view(client: Client, global_data: &GammaControlManagerGlobalData) -> bool {
+        (global_data.filter)(&client)
+    }
+}
+
+impl<D> Dispatch<ZwlrGammaControlManagerV1, (), D> for GammaControlManagerState
+where
+    D: Dispatch<ZwlrGammaControlManagerV1, ()>,
+    D: Dispatch<ZwlrGammaControlV1, GammaControlState>,
+    D: GammaControlHandler,
+    D: 'static,
+{
+    fn request(
+        state: &mut D,
+        _client: &Client,
+        _resource: &ZwlrGammaControlManagerV1,
+        request: <ZwlrGammaControlManagerV1 as Resource>::Request,
+        _data: &(),
+        _dhandle: &DisplayHandle,
+        data_init: &mut DataInit<'_, D>,
+    ) {
+        match request {
+            zwlr_gamma_control_manager_v1::Request::GetGammaControl { id, output } => {
+                if let Some(output) = Output::from_resource(&output) {
+                    // We borrow state in the middle.
+                    #[allow(clippy::map_entry)]
+                    if !state
+                        .gamma_control_manager_state()
+                        .gamma_controls
+                        .contains_key(&output)
+                    {
+                        if let Some(gamma_size) = state.get_gamma_size(&output) {
+                            let zwlr_gamma_control =
+                                data_init.init(id, GammaControlState { gamma_size });
+                            zwlr_gamma_control.gamma_size(gamma_size);
+                            state
+                                .gamma_control_manager_state()
+                                .gamma_controls
+                                .insert(output, zwlr_gamma_control);
+                            return;
+                        }
+                    }
+                }
+
+                data_init
+                    .init(id, GammaControlState { gamma_size: 0 })
+                    .failed();
+            }
+            zwlr_gamma_control_manager_v1::Request::Destroy => (),
+            _ => unreachable!(),
+        }
+    }
+}
+
+impl<D> Dispatch<ZwlrGammaControlV1, GammaControlState, D> for GammaControlManagerState
+where
+    D: Dispatch<ZwlrGammaControlV1, GammaControlState>,
+    D: GammaControlHandler,
+    D: 'static,
+{
+    fn request(
+        state: &mut D,
+        _client: &Client,
+        resource: &ZwlrGammaControlV1,
+        request: <ZwlrGammaControlV1 as Resource>::Request,
+        data: &GammaControlState,
+        _dhandle: &DisplayHandle,
+        _data_init: &mut DataInit<'_, D>,
+    ) {
+        match request {
+            zwlr_gamma_control_v1::Request::SetGamma { fd } => {
+                let gamma_controls = &mut state.gamma_control_manager_state().gamma_controls;
+                let Some((output, _)) = gamma_controls.iter().find(|(_, x)| *x == resource) else {
+                    return;
+                };
+                let output = output.clone();
+
+                trace!("setting gamma for output {}", output.name());
+
+                // Start with a u16 slice so it's aligned correctly.
+                let mut gamma = vec![0u16; data.gamma_size as usize * 3];
+                let buf = bytemuck::cast_slice_mut(&mut gamma);
+                let mut file = File::from(fd);
+                {
+                    let _span = tracy_client::span!("read gamma from fd");
+
+                    if let Err(err) = file.read_exact(buf) {
+                        warn!("failed to read gamma data: {err:?}");
+                        resource.failed();
+                        gamma_controls.remove(&output);
+                        let _ = state.set_gamma(&output, None);
+                        return;
+                    }
+
+                    // Verify that there's no more data.
+                    #[allow(clippy::unused_io_amount)] // False positive on 1.77.0
+                    {
+                        match file.read(&mut [0]) {
+                            Ok(0) => (),
+                            Ok(_) => {
+                                warn!("gamma data is too large");
+                                resource.failed();
+                                gamma_controls.remove(&output);
+                                let _ = state.set_gamma(&output, None);
+                                return;
+                            }
+                            Err(err) => {
+                                warn!("error reading gamma data: {err:?}");
+                                resource.failed();
+                                gamma_controls.remove(&output);
+                                let _ = state.set_gamma(&output, None);
+                                return;
+                            }
+                        }
+                    }
+                }
+
+                if state.set_gamma(&output, Some(gamma)).is_none() {
+                    resource.failed();
+                    let gamma_controls = &mut state.gamma_control_manager_state().gamma_controls;
+                    gamma_controls.remove(&output);
+                    let _ = state.set_gamma(&output, None);
+                }
+            }
+            zwlr_gamma_control_v1::Request::Destroy => (),
+            _ => unreachable!(),
+        }
+    }
+
+    fn destroyed(
+        state: &mut D,
+        _client: ClientId,
+        resource: &ZwlrGammaControlV1,
+        _data: &GammaControlState,
+    ) {
+        let gamma_controls = &mut state.gamma_control_manager_state().gamma_controls;
+        let Some((output, _)) = gamma_controls.iter().find(|(_, x)| *x == resource) else {
+            return;
+        };
+        let output = output.clone();
+        gamma_controls.remove(&output);
+
+        let _ = state.set_gamma(&output, None);
+    }
+}
+
+#[macro_export]
+macro_rules! delegate_gamma_control {
+    ($(@<$( $lt:tt $( : $clt:tt $(+ $dlt:tt )* )? ),+>)? $ty: ty) => {
+        smithay::reexports::wayland_server::delegate_global_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            smithay::reexports::wayland_protocols_wlr::gamma_control::v1::server::zwlr_gamma_control_manager_v1::ZwlrGammaControlManagerV1: $crate::protocols::gamma_control::GammaControlManagerGlobalData
+        ] => $crate::protocols::gamma_control::GammaControlManagerState);
+
+        smithay::reexports::wayland_server::delegate_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            smithay::reexports::wayland_protocols_wlr::gamma_control::v1::server::zwlr_gamma_control_manager_v1::ZwlrGammaControlManagerV1: ()
+        ] => $crate::protocols::gamma_control::GammaControlManagerState);
+
+        smithay::reexports::wayland_server::delegate_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            smithay::reexports::wayland_protocols_wlr::gamma_control::v1::server::zwlr_gamma_control_v1::ZwlrGammaControlV1:  $crate::protocols::gamma_control::GammaControlState
+        ] => $crate::protocols::gamma_control::GammaControlManagerState);
+    };
+}

src/protocols/mod.rs

@@ -0,0 +1,3 @@
+pub mod foreign_toplevel;
+pub mod gamma_control;
+pub mod screencopy;

src/protocols/screencopy.rs

@@ -0,0 +1,386 @@
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::Arc;
+use std::time::UNIX_EPOCH;
+
+use smithay::output::Output;
+use smithay::reexports::wayland_protocols_wlr::screencopy::v1::server::zwlr_screencopy_frame_v1::{
+    Flags, ZwlrScreencopyFrameV1,
+};
+use smithay::reexports::wayland_protocols_wlr::screencopy::v1::server::zwlr_screencopy_manager_v1::ZwlrScreencopyManagerV1;
+use smithay::reexports::wayland_protocols_wlr::screencopy::v1::server::{
+    zwlr_screencopy_frame_v1, zwlr_screencopy_manager_v1,
+};
+use smithay::reexports::wayland_server::protocol::wl_buffer::WlBuffer;
+use smithay::reexports::wayland_server::protocol::wl_shm;
+use smithay::reexports::wayland_server::{
+    Client, DataInit, Dispatch, DisplayHandle, GlobalDispatch, New, Resource,
+};
+use smithay::utils::{Physical, Point, Rectangle, Size};
+use smithay::wayland::shm;
+
+// We do not support copy_with_damage() semantics yet.
+const VERSION: u32 = 1;
+
+pub struct ScreencopyManagerState;
+
+pub struct ScreencopyManagerGlobalData {
+    filter: Box<dyn for<'c> Fn(&'c Client) -> bool + Send + Sync>,
+}
+
+impl ScreencopyManagerState {
+    pub fn new<D, F>(display: &DisplayHandle, filter: F) -> Self
+    where
+        D: GlobalDispatch<ZwlrScreencopyManagerV1, ScreencopyManagerGlobalData>,
+        D: Dispatch<ZwlrScreencopyManagerV1, ()>,
+        D: Dispatch<ZwlrScreencopyFrameV1, ScreencopyFrameState>,
+        D: ScreencopyHandler,
+        D: 'static,
+        F: for<'c> Fn(&'c Client) -> bool + Send + Sync + 'static,
+    {
+        let global_data = ScreencopyManagerGlobalData {
+            filter: Box::new(filter),
+        };
+        display.create_global::<D, ZwlrScreencopyManagerV1, _>(VERSION, global_data);
+
+        Self
+    }
+}
+
+impl<D> GlobalDispatch<ZwlrScreencopyManagerV1, ScreencopyManagerGlobalData, D>
+    for ScreencopyManagerState
+where
+    D: GlobalDispatch<ZwlrScreencopyManagerV1, ScreencopyManagerGlobalData>,
+    D: Dispatch<ZwlrScreencopyManagerV1, ()>,
+    D: Dispatch<ZwlrScreencopyFrameV1, ScreencopyFrameState>,
+    D: ScreencopyHandler,
+    D: 'static,
+{
+    fn bind(
+        _state: &mut D,
+        _display: &DisplayHandle,
+        _client: &Client,
+        manager: New<ZwlrScreencopyManagerV1>,
+        _manager_state: &ScreencopyManagerGlobalData,
+        data_init: &mut DataInit<'_, D>,
+    ) {
+        data_init.init(manager, ());
+    }
+
+    fn can_view(client: Client, global_data: &ScreencopyManagerGlobalData) -> bool {
+        (global_data.filter)(&client)
+    }
+}
+
+impl<D> Dispatch<ZwlrScreencopyManagerV1, (), D> for ScreencopyManagerState
+where
+    D: GlobalDispatch<ZwlrScreencopyManagerV1, ScreencopyManagerGlobalData>,
+    D: Dispatch<ZwlrScreencopyManagerV1, ()>,
+    D: Dispatch<ZwlrScreencopyFrameV1, ScreencopyFrameState>,
+    D: ScreencopyHandler,
+    D: 'static,
+{
+    fn request(
+        _state: &mut D,
+        _client: &Client,
+        _manager: &ZwlrScreencopyManagerV1,
+        request: zwlr_screencopy_manager_v1::Request,
+        _data: &(),
+        _display: &DisplayHandle,
+        data_init: &mut DataInit<'_, D>,
+    ) {
+        let (frame, overlay_cursor, buffer_size, region_loc, output) = match request {
+            zwlr_screencopy_manager_v1::Request::CaptureOutput {
+                frame,
+                overlay_cursor,
+                output,
+            } => {
+                let output = Output::from_resource(&output).unwrap();
+                let buffer_size = output.current_mode().unwrap().size;
+                let region_loc = Point::from((0, 0));
+
+                (frame, overlay_cursor, buffer_size, region_loc, output)
+            }
+            zwlr_screencopy_manager_v1::Request::CaptureOutputRegion {
+                frame,
+                overlay_cursor,
+                x,
+                y,
+                width,
+                height,
+                output,
+            } => {
+                if width <= 0 || height <= 0 {
+                    trace!("screencopy client requested invalid sized region");
+                    let frame = data_init.init(frame, ScreencopyFrameState::Failed);
+                    frame.failed();
+                    return;
+                }
+
+                let output = Output::from_resource(&output).unwrap();
+                let output_transform = output.current_transform();
+                let output_physical_size =
+                    output_transform.transform_size(output.current_mode().unwrap().size);
+                let output_rect = Rectangle::from_loc_and_size((0, 0), output_physical_size);
+
+                let rect = Rectangle::from_loc_and_size((x, y), (width, height));
+
+                let output_scale = output.current_scale().integer_scale();
+                let physical_rect = rect.to_physical(output_scale);
+
+                // Clamp captured region to the output.
+                let Some(clamped_rect) = physical_rect.intersection(output_rect) else {
+                    trace!("screencopy client requested region outside of output");
+                    let frame = data_init.init(frame, ScreencopyFrameState::Failed);
+                    frame.failed();
+                    return;
+                };
+
+                let untransformed_rect = output_transform
+                    .invert()
+                    .transform_rect_in(clamped_rect, &output_physical_size);
+
+                (
+                    frame,
+                    overlay_cursor,
+                    untransformed_rect.size,
+                    clamped_rect.loc,
+                    output,
+                )
+            }
+            zwlr_screencopy_manager_v1::Request::Destroy => return,
+            _ => unreachable!(),
+        };
+
+        // Create the frame.
+        let overlay_cursor = overlay_cursor != 0;
+        let info = ScreencopyFrameInfo {
+            output,
+            overlay_cursor,
+            buffer_size,
+            region_loc,
+        };
+        let frame = data_init.init(
+            frame,
+            ScreencopyFrameState::Pending {
+                info,
+                copied: Arc::new(AtomicBool::new(false)),
+            },
+        );
+
+        // Send desired SHM buffer parameters.
+        frame.buffer(
+            wl_shm::Format::Argb8888,
+            buffer_size.w as u32,
+            buffer_size.h as u32,
+            buffer_size.w as u32 * 4,
+        );
+
+        // if manager.version() >= 3 {
+        //     // Send desired DMA buffer parameters.
+        //     frame.linux_dmabuf(
+        //         Fourcc::Argb8888 as u32,
+        //         buffer_size.w as u32,
+        //         buffer_size.h as u32,
+        //     );
+        //
+        //     // Notify client that all supported buffers were enumerated.
+        //     frame.buffer_done();
+        // }
+    }
+}
+
+/// Handler trait for wlr-screencopy.
+pub trait ScreencopyHandler {
+    /// Handle new screencopy request.
+    fn frame(&mut self, frame: Screencopy);
+}
+
+#[allow(missing_docs)]
+#[macro_export]
+macro_rules! delegate_screencopy {
+    ($(@<$( $lt:tt $( : $clt:tt $(+ $dlt:tt )* )? ),+>)? $ty: ty) => {
+        smithay::reexports::wayland_server::delegate_global_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            smithay::reexports::wayland_protocols_wlr::screencopy::v1::server::zwlr_screencopy_manager_v1::ZwlrScreencopyManagerV1: $crate::protocols::screencopy::ScreencopyManagerGlobalData
+        ] => $crate::protocols::screencopy::ScreencopyManagerState);
+
+        smithay::reexports::wayland_server::delegate_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            smithay::reexports::wayland_protocols_wlr::screencopy::v1::server::zwlr_screencopy_manager_v1::ZwlrScreencopyManagerV1: ()
+        ] => $crate::protocols::screencopy::ScreencopyManagerState);
+
+        smithay::reexports::wayland_server::delegate_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            smithay::reexports::wayland_protocols_wlr::screencopy::v1::server::zwlr_screencopy_frame_v1::ZwlrScreencopyFrameV1: $crate::protocols::screencopy::ScreencopyFrameState
+        ] => $crate::protocols::screencopy::ScreencopyManagerState);
+    };
+}
+
+#[derive(Clone)]
+pub struct ScreencopyFrameInfo {
+    output: Output,
+    buffer_size: Size<i32, Physical>,
+    region_loc: Point<i32, Physical>,
+    overlay_cursor: bool,
+}
+
+pub enum ScreencopyFrameState {
+    Failed,
+    Pending {
+        info: ScreencopyFrameInfo,
+        copied: Arc<AtomicBool>,
+    },
+}
+
+impl<D> Dispatch<ZwlrScreencopyFrameV1, ScreencopyFrameState, D> for ScreencopyManagerState
+where
+    D: Dispatch<ZwlrScreencopyFrameV1, ScreencopyFrameState>,
+    D: ScreencopyHandler,
+    D: 'static,
+{
+    fn request(
+        state: &mut D,
+        _client: &Client,
+        frame: &ZwlrScreencopyFrameV1,
+        request: zwlr_screencopy_frame_v1::Request,
+        data: &ScreencopyFrameState,
+        _display: &DisplayHandle,
+        _data_init: &mut DataInit<'_, D>,
+    ) {
+        if matches!(request, zwlr_screencopy_frame_v1::Request::Destroy) {
+            return;
+        }
+
+        let (info, copied) = match data {
+            ScreencopyFrameState::Failed => return,
+            ScreencopyFrameState::Pending { info, copied } => (info, copied),
+        };
+
+        if copied.load(Ordering::SeqCst) {
+            frame.post_error(
+                zwlr_screencopy_frame_v1::Error::AlreadyUsed,
+                "copy was already requested",
+            );
+            return;
+        }
+
+        let (buffer, with_damage) = match request {
+            zwlr_screencopy_frame_v1::Request::Copy { buffer } => (buffer, false),
+            // zwlr_screencopy_frame_v1::Request::CopyWithDamage { buffer } => (buffer, true),
+            _ => unreachable!(),
+        };
+
+        if !shm::with_buffer_contents(&buffer, |_buf, shm_len, buffer_data| {
+            buffer_data.format == wl_shm::Format::Argb8888
+                && buffer_data.stride == info.buffer_size.w * 4
+                && buffer_data.height == info.buffer_size.h
+                && shm_len as i32 == buffer_data.stride * buffer_data.height
+        })
+        .unwrap_or(false)
+        {
+            frame.post_error(
+                zwlr_screencopy_frame_v1::Error::InvalidBuffer,
+                "invalid buffer",
+            );
+            return;
+        }
+
+        copied.store(true, Ordering::SeqCst);
+
+        state.frame(Screencopy {
+            with_damage,
+            buffer,
+            frame: frame.clone(),
+            info: info.clone(),
+            submitted: false,
+        });
+    }
+}
+
+/// Screencopy frame.
+pub struct Screencopy {
+    info: ScreencopyFrameInfo,
+    frame: ZwlrScreencopyFrameV1,
+    #[allow(unused)]
+    with_damage: bool,
+    buffer: WlBuffer,
+    submitted: bool,
+}
+
+impl Drop for Screencopy {
+    fn drop(&mut self) {
+        if !self.submitted {
+            self.frame.failed();
+        }
+    }
+}
+
+impl Screencopy {
+    /// Get the target buffer to copy to.
+    pub fn buffer(&self) -> &WlBuffer {
+        &self.buffer
+    }
+
+    pub fn region_loc(&self) -> Point<i32, Physical> {
+        self.info.region_loc
+    }
+
+    pub fn buffer_size(&self) -> Size<i32, Physical> {
+        self.info.buffer_size
+    }
+
+    pub fn output(&self) -> &Output {
+        &self.info.output
+    }
+
+    pub fn overlay_cursor(&self) -> bool {
+        self.info.overlay_cursor
+    }
+
+    // pub fn damage(&mut self, damage: &[Rectangle<i32, Physical>]) {
+    //     assert!(self.with_damage);
+    //
+    //     for Rectangle { loc, size } in damage {
+    //         self.frame
+    //             .damage(loc.x as u32, loc.y as u32, size.w as u32, size.h as u32);
+    //     }
+    // }
+
+    /// Submit the copied content.
+    pub fn submit(mut self, y_invert: bool) {
+        // Notify client that buffer is ordinary.
+        self.frame.flags(if y_invert {
+            Flags::YInvert
+        } else {
+            Flags::empty()
+        });
+
+        // Notify client about successful copy.
+        let time = UNIX_EPOCH.elapsed().unwrap();
+        let tv_sec_hi = (time.as_secs() >> 32) as u32;
+        let tv_sec_lo = (time.as_secs() & 0xFFFFFFFF) as u32;
+        let tv_nsec = time.subsec_nanos();
+        self.frame.ready(tv_sec_hi, tv_sec_lo, tv_nsec);
+
+        // Mark frame as submitted to ensure destructor isn't run.
+        self.submitted = true;
+    }
+
+    // pub fn submit_after_sync<T>(
+    //     self,
+    //     y_invert: bool,
+    //     sync_point: Option<OwnedFd>,
+    //     event_loop: &LoopHandle<'_, T>,
+    // ) {
+    //     match sync_point {
+    //         None => self.submit(y_invert),
+    //         Some(sync_fd) => {
+    //             let source = Generic::new(sync_fd, Interest::READ, Mode::OneShot);
+    //             let mut screencopy = Some(self);
+    //             event_loop
+    //                 .insert_source(source, move |_, _, _| {
+    //                     screencopy.take().unwrap().submit(y_invert);
+    //                     Ok(PostAction::Remove)
+    //                 })
+    //                 .unwrap();
+    //         }
+    //     }
+    // }
+}

src/pw_utils.rs

@@ -7,42 +7,48 @@ use std::rc::Rc;
 use std::time::Duration;
 
 use anyhow::Context as _;
-use pipewire::spa::data::DataType;
+use pipewire::context::Context;
-use pipewire::spa::format::{FormatProperties, MediaSubtype, MediaType};
+use pipewire::core::Core;
+use pipewire::main_loop::MainLoop;
+use pipewire::properties::Properties;
+use pipewire::spa::buffer::DataType;
+use pipewire::spa::param::format::{FormatProperties, MediaSubtype, MediaType};
 use pipewire::spa::param::format_utils::parse_format;
 use pipewire::spa::param::video::{VideoFormat, VideoInfoRaw};
 use pipewire::spa::param::ParamType;
 use pipewire::spa::pod::serialize::PodSerializer;
 use pipewire::spa::pod::{self, ChoiceValue, Pod, Property, PropertyFlags};
 use pipewire::spa::sys::*;
-use pipewire::spa::utils::{Choice, ChoiceEnum, ChoiceFlags, Fraction, Rectangle, SpaTypes};
+use pipewire::spa::utils::{
-use pipewire::spa::Direction;
+    Choice, ChoiceEnum, ChoiceFlags, Direction, Fraction, Rectangle, SpaTypes,
+};
 use pipewire::stream::{Stream, StreamFlags, StreamListener, StreamState};
-use pipewire::{Context, Core, MainLoop, Properties};
 use smithay::backend::allocator::dmabuf::{AsDmabuf, Dmabuf};
 use smithay::backend::allocator::gbm::{GbmBufferFlags, GbmDevice};
 use smithay::backend::allocator::Fourcc;
 use smithay::backend::drm::DrmDeviceFd;
 use smithay::output::Output;
 use smithay::reexports::calloop::generic::Generic;
-use smithay::reexports::calloop::{self, Interest, LoopHandle, Mode, PostAction};
+use smithay::reexports::calloop::{Interest, LoopHandle, Mode, PostAction};
 use smithay::reexports::gbm::Modifier;
+use smithay::utils::{Physical, Size};
 use zbus::SignalContext;
 
 use crate::dbus::mutter_screen_cast::{self, CursorMode, ScreenCastToNiri};
 use crate::niri::State;
 
 pub struct PipeWire {
-    _context: Context<MainLoop>,
+    _context: Context,
     pub core: Core,
 }
 
 pub struct Cast {
     pub session_id: usize,
-    pub stream: Rc<Stream>,
+    pub stream: Stream,
     _listener: StreamListener<()>,
     pub is_active: Rc<Cell<bool>>,
     pub output: Output,
+    pub size: Size<i32, Physical>,
     pub cursor_mode: CursorMode,
     pub last_frame_time: Duration,
     pub min_time_between_frames: Rc<Cell<Duration>>,
@@ -51,7 +57,7 @@ pub struct Cast {
 
 impl PipeWire {
     pub fn new(event_loop: &LoopHandle<'static, State>) -> anyhow::Result<Self> {
-        let main_loop = MainLoop::new().context("error creating MainLoop")?;
+        let main_loop = MainLoop::new(None).context("error creating MainLoop")?;
         let context = Context::new(&main_loop).context("error creating Context")?;
         let core = context.connect(None).context("error creating Core")?;
 
@@ -66,14 +72,14 @@ impl PipeWire {
         struct AsFdWrapper(MainLoop);
         impl AsFd for AsFdWrapper {
             fn as_fd(&self) -> BorrowedFd<'_> {
-                self.0.fd()
+                self.0.loop_().fd()
             }
         }
         let generic = Generic::new(AsFdWrapper(main_loop), Interest::READ, Mode::Level);
         event_loop
             .insert_source(generic, move |_, wrapper, _| {
                 let _span = tracy_client::span!("pipewire iteration");
-                wrapper.0.iterate(Duration::ZERO);
+                wrapper.0.loop_().iterate(Duration::ZERO);
                 Ok(PostAction::Continue)
             })
             .unwrap();
@@ -112,13 +118,14 @@ impl PipeWire {
 
         let mode = output.current_mode().unwrap();
         let size = mode.size;
+        let transform = output.current_transform();
+        let size = transform.transform_size(size);
         let refresh = mode.refresh;
 
         let stream = Stream::new(&self.core, "niri-screen-cast-src", Properties::new())
             .context("error creating Stream")?;
 
         // Like in good old wayland-rs times...
-        let stream = Rc::new(stream);
         let node_id = Rc::new(Cell::new(None));
         let is_active = Rc::new(Cell::new(false));
         let min_time_between_frames = Rc::new(Cell::new(Duration::ZERO));
@@ -127,10 +134,9 @@ impl PipeWire {
         let listener = stream
             .add_local_listener_with_user_data(())
             .state_changed({
-                let stream = stream.clone();
                 let is_active = is_active.clone();
                 let stop_cast = stop_cast.clone();
-                move |old, new| {
+                move |stream, (), old, new| {
                     debug!("pw stream: state changed: {old:?} -> {new:?}");
 
                     match new {
@@ -174,7 +180,7 @@ impl PipeWire {
             })
             .param_changed({
                 let min_time_between_frames = min_time_between_frames.clone();
-                move |stream, id, _data, pod| {
+                move |stream, (), id, pod| {
                     let id = ParamType::from_raw(id);
                     trace!(?id, "pw stream: param_changed");
 
@@ -256,8 +262,7 @@ impl PipeWire {
                     let mut b1 = vec![];
                     // let mut b2 = vec![];
                     let mut params = [
-                        make_pod(&mut b1, o1).as_raw_ptr().cast_const(),
+                        make_pod(&mut b1, o1), // make_pod(&mut b2, o2)
-                        // make_pod(&mut b2, o2).as_raw_ptr().cast_const(),
                     ];
                     stream.update_params(&mut params).unwrap();
                 }
@@ -265,7 +270,7 @@ impl PipeWire {
             .add_buffer({
                 let dmabufs = dmabufs.clone();
                 let stop_cast = stop_cast.clone();
-                move |buffer| {
+                move |_stream, (), buffer| {
                     trace!("pw stream: add_buffer");
 
                     unsafe {
@@ -309,7 +314,7 @@ impl PipeWire {
             })
             .remove_buffer({
                 let dmabufs = dmabufs.clone();
-                move |buffer| {
+                move |_stream, (), buffer| {
                     trace!("pw stream: remove_buffer");
 
                     unsafe {
@@ -383,6 +388,7 @@ impl PipeWire {
             _listener: listener,
             is_active,
             output,
+            size,
             cursor_mode,
             last_frame_time: Duration::ZERO,
             min_time_between_frames,

src/render_helpers/crossfade.rs

@@ -0,0 +1,162 @@
+use std::collections::HashMap;
+
+use smithay::backend::renderer::element::{Element, Id, Kind, RenderElement, UnderlyingStorage};
+use smithay::backend::renderer::gles::{GlesError, GlesFrame, GlesRenderer, GlesTexture, Uniform};
+use smithay::backend::renderer::utils::{CommitCounter, DamageSet};
+use smithay::utils::{Buffer, Logical, Physical, Rectangle, Scale, Size, Transform};
+
+use super::primary_gpu_pixel_shader_with_textures::PrimaryGpuPixelShaderWithTexturesRenderElement;
+use super::renderer::AsGlesFrame;
+use super::shaders::Shaders;
+use crate::backend::tty::{TtyFrame, TtyRenderer, TtyRendererError};
+
+#[derive(Debug)]
+pub struct CrossfadeRenderElement(PrimaryGpuPixelShaderWithTexturesRenderElement);
+
+impl CrossfadeRenderElement {
+    #[allow(clippy::too_many_arguments)]
+    pub fn new(
+        renderer: &mut GlesRenderer,
+        area: Rectangle<i32, Logical>,
+        scale: Scale<f64>,
+        texture_from: (GlesTexture, Rectangle<i32, Physical>),
+        size_from: Size<i32, Logical>,
+        texture_to: (GlesTexture, Rectangle<i32, Physical>),
+        size_to: Size<i32, Logical>,
+        amount: f32,
+        result_alpha: f32,
+    ) -> Option<Self> {
+        let (texture_from, texture_from_geo) = texture_from;
+        let (texture_to, texture_to_geo) = texture_to;
+
+        let scale_from = area.size.to_f64() / size_from.to_f64();
+        let scale_to = area.size.to_f64() / size_to.to_f64();
+
+        let tex_from_geo = texture_from_geo.to_f64().upscale(scale_from);
+        let tex_to_geo = texture_to_geo.to_f64().upscale(scale_to);
+        let combined_geo = tex_from_geo.merge(tex_to_geo);
+
+        let size = combined_geo
+            .size
+            .to_logical(1.)
+            .to_buffer(1., Transform::Normal);
+
+        let area = Rectangle::from_loc_and_size(
+            area.loc + combined_geo.loc.to_logical(scale).to_i32_round(),
+            combined_geo.size.to_logical(scale).to_i32_round(),
+        );
+
+        let tex_from_loc = (tex_from_geo.loc - combined_geo.loc)
+            .downscale((combined_geo.size.w, combined_geo.size.h));
+        let tex_to_loc = (tex_to_geo.loc - combined_geo.loc)
+            .downscale((combined_geo.size.w, combined_geo.size.h));
+        let tex_from_size = tex_from_geo.size / combined_geo.size;
+        let tex_to_size = tex_to_geo.size / combined_geo.size;
+
+        // FIXME: cropping this element will mess up the coordinates.
+        Shaders::get(renderer).crossfade.clone().map(|shader| {
+            Self(PrimaryGpuPixelShaderWithTexturesRenderElement::new(
+                shader,
+                HashMap::from([
+                    (String::from("tex_from"), texture_from),
+                    (String::from("tex_to"), texture_to),
+                ]),
+                area,
+                size,
+                None,
+                result_alpha,
+                vec![
+                    Uniform::new(
+                        "tex_from_loc",
+                        (tex_from_loc.x as f32, tex_from_loc.y as f32),
+                    ),
+                    Uniform::new(
+                        "tex_from_size",
+                        (tex_from_size.x as f32, tex_from_size.y as f32),
+                    ),
+                    Uniform::new("tex_to_loc", (tex_to_loc.x as f32, tex_to_loc.y as f32)),
+                    Uniform::new("tex_to_size", (tex_to_size.x as f32, tex_to_size.y as f32)),
+                    Uniform::new("amount", amount),
+                ],
+                Kind::Unspecified,
+            ))
+        })
+    }
+}
+
+impl Element for CrossfadeRenderElement {
+    fn id(&self) -> &Id {
+        self.0.id()
+    }
+
+    fn current_commit(&self) -> CommitCounter {
+        self.0.current_commit()
+    }
+
+    fn geometry(&self, scale: Scale<f64>) -> Rectangle<i32, Physical> {
+        self.0.geometry(scale)
+    }
+
+    fn transform(&self) -> Transform {
+        self.0.transform()
+    }
+
+    fn src(&self) -> Rectangle<f64, Buffer> {
+        self.0.src()
+    }
+
+    fn damage_since(
+        &self,
+        scale: Scale<f64>,
+        commit: Option<CommitCounter>,
+    ) -> DamageSet<i32, Physical> {
+        self.0.damage_since(scale, commit)
+    }
+
+    fn opaque_regions(&self, scale: Scale<f64>) -> Vec<Rectangle<i32, Physical>> {
+        self.0.opaque_regions(scale)
+    }
+
+    fn alpha(&self) -> f32 {
+        self.0.alpha()
+    }
+
+    fn kind(&self) -> Kind {
+        self.0.kind()
+    }
+}
+
+impl RenderElement<GlesRenderer> for CrossfadeRenderElement {
+    fn draw(
+        &self,
+        frame: &mut GlesFrame<'_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), GlesError> {
+        RenderElement::<GlesRenderer>::draw(&self.0, frame, src, dst, damage)?;
+        Ok(())
+    }
+
+    fn underlying_storage(&self, renderer: &mut GlesRenderer) -> Option<UnderlyingStorage> {
+        self.0.underlying_storage(renderer)
+    }
+}
+
+impl<'render> RenderElement<TtyRenderer<'render>> for CrossfadeRenderElement {
+    fn draw(
+        &self,
+        frame: &mut TtyFrame<'_, '_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), TtyRendererError<'render>> {
+        let gles_frame = frame.as_gles_frame();
+        RenderElement::<GlesRenderer>::draw(&self.0, gles_frame, src, dst, damage)?;
+        Ok(())
+    }
+
+    fn underlying_storage(&self, renderer: &mut TtyRenderer<'render>) -> Option<UnderlyingStorage> {
+        self.0.underlying_storage(renderer)
+    }
+}

src/render_helpers/gradient.rs

@@ -0,0 +1,135 @@
+use glam::Vec2;
+use smithay::backend::renderer::element::{Element, Id, Kind, RenderElement, UnderlyingStorage};
+use smithay::backend::renderer::gles::element::PixelShaderElement;
+use smithay::backend::renderer::gles::{GlesError, GlesFrame, GlesRenderer, Uniform};
+use smithay::backend::renderer::utils::{CommitCounter, DamageSet};
+use smithay::utils::{Buffer, Logical, Physical, Rectangle, Scale, Transform};
+
+use super::primary_gpu_pixel_shader::PrimaryGpuPixelShaderRenderElement;
+use super::renderer::NiriRenderer;
+use super::shaders::Shaders;
+use crate::backend::tty::{TtyFrame, TtyRenderer, TtyRendererError};
+
+/// Renders a sub- or super-rect of an angled linear gradient like CSS linear-gradient(angle, a, b).
+#[derive(Debug)]
+pub struct GradientRenderElement(PrimaryGpuPixelShaderRenderElement);
+
+impl GradientRenderElement {
+    pub fn new(
+        renderer: &mut impl NiriRenderer,
+        scale: Scale<f64>,
+        area: Rectangle<i32, Logical>,
+        gradient_area: Rectangle<i32, Logical>,
+        color_from: [f32; 4],
+        color_to: [f32; 4],
+        angle: f32,
+    ) -> Option<Self> {
+        let shader = Shaders::get(renderer).gradient_border.clone()?;
+        let grad_offset = (area.loc - gradient_area.loc).to_f64().to_physical(scale);
+
+        let grad_dir = Vec2::from_angle(angle);
+
+        let grad_area_size = gradient_area.size.to_f64().to_physical(scale);
+        let (w, h) = (grad_area_size.w as f32, grad_area_size.h as f32);
+
+        let mut grad_area_diag = Vec2::new(w, h);
+        if (grad_dir.x < 0. && 0. <= grad_dir.y) || (0. <= grad_dir.x && grad_dir.y < 0.) {
+            grad_area_diag.x = -w;
+        }
+
+        let mut grad_vec = grad_area_diag.project_onto(grad_dir);
+        if grad_dir.y <= 0. {
+            grad_vec = -grad_vec;
+        }
+
+        let elem = PixelShaderElement::new(
+            shader,
+            area,
+            None,
+            1.,
+            vec![
+                Uniform::new("color_from", color_from),
+                Uniform::new("color_to", color_to),
+                Uniform::new("grad_offset", (grad_offset.x as f32, grad_offset.y as f32)),
+                Uniform::new("grad_width", w),
+                Uniform::new("grad_vec", grad_vec.to_array()),
+            ],
+            Kind::Unspecified,
+        );
+        Some(Self(PrimaryGpuPixelShaderRenderElement(elem)))
+    }
+}
+
+impl Element for GradientRenderElement {
+    fn id(&self) -> &Id {
+        self.0.id()
+    }
+
+    fn current_commit(&self) -> CommitCounter {
+        self.0.current_commit()
+    }
+
+    fn geometry(&self, scale: Scale<f64>) -> Rectangle<i32, Physical> {
+        self.0.geometry(scale)
+    }
+
+    fn transform(&self) -> Transform {
+        self.0.transform()
+    }
+
+    fn src(&self) -> Rectangle<f64, Buffer> {
+        self.0.src()
+    }
+
+    fn damage_since(
+        &self,
+        scale: Scale<f64>,
+        commit: Option<CommitCounter>,
+    ) -> DamageSet<i32, Physical> {
+        self.0.damage_since(scale, commit)
+    }
+
+    fn opaque_regions(&self, scale: Scale<f64>) -> Vec<Rectangle<i32, Physical>> {
+        self.0.opaque_regions(scale)
+    }
+
+    fn alpha(&self) -> f32 {
+        self.0.alpha()
+    }
+
+    fn kind(&self) -> Kind {
+        self.0.kind()
+    }
+}
+
+impl RenderElement<GlesRenderer> for GradientRenderElement {
+    fn draw(
+        &self,
+        frame: &mut GlesFrame<'_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), GlesError> {
+        RenderElement::<GlesRenderer>::draw(&self.0, frame, src, dst, damage)
+    }
+
+    fn underlying_storage(&self, renderer: &mut GlesRenderer) -> Option<UnderlyingStorage> {
+        self.0.underlying_storage(renderer)
+    }
+}
+
+impl<'render> RenderElement<TtyRenderer<'render>> for GradientRenderElement {
+    fn draw(
+        &self,
+        frame: &mut TtyFrame<'_, '_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), TtyRendererError<'render>> {
+        RenderElement::<TtyRenderer<'_>>::draw(&self.0, frame, src, dst, damage)
+    }
+
+    fn underlying_storage(&self, renderer: &mut TtyRenderer<'render>) -> Option<UnderlyingStorage> {
+        self.0.underlying_storage(renderer)
+    }
+}

src/render_helpers/mod.rs

@@ -0,0 +1,276 @@
+use std::ptr;
+
+use anyhow::{ensure, Context};
+use smithay::backend::allocator::Fourcc;
+use smithay::backend::renderer::element::solid::{SolidColorBuffer, SolidColorRenderElement};
+use smithay::backend::renderer::element::texture::{TextureBuffer, TextureRenderElement};
+use smithay::backend::renderer::element::utils::{Relocate, RelocateRenderElement};
+use smithay::backend::renderer::element::{Kind, RenderElement};
+use smithay::backend::renderer::gles::{GlesMapping, GlesRenderer, GlesTexture};
+use smithay::backend::renderer::sync::SyncPoint;
+use smithay::backend::renderer::{buffer_dimensions, Bind, ExportMem, Frame, Offscreen, Renderer};
+use smithay::reexports::wayland_server::protocol::wl_buffer::WlBuffer;
+use smithay::reexports::wayland_server::protocol::wl_shm;
+use smithay::utils::{Logical, Physical, Point, Rectangle, Scale, Size, Transform};
+use smithay::wayland::shm;
+
+use self::primary_gpu_texture::PrimaryGpuTextureRenderElement;
+
+pub mod crossfade;
+pub mod gradient;
+pub mod offscreen;
+pub mod primary_gpu_pixel_shader;
+pub mod primary_gpu_pixel_shader_with_textures;
+pub mod primary_gpu_texture;
+pub mod render_elements;
+pub mod renderer;
+pub mod resources;
+pub mod shaders;
+pub mod snapshot;
+pub mod surface;
+
+/// What we're rendering for.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum RenderTarget {
+    /// Rendering to display on screen.
+    Output,
+    /// Rendering for a screencast.
+    Screencast,
+    /// Rendering for any other screen capture.
+    ScreenCapture,
+}
+
+/// Buffer with location, src and dst.
+#[derive(Debug)]
+pub struct BakedBuffer<B> {
+    pub buffer: B,
+    pub location: Point<i32, Logical>,
+    pub src: Option<Rectangle<f64, Logical>>,
+    pub dst: Option<Size<i32, Logical>>,
+}
+
+pub trait ToRenderElement {
+    type RenderElement;
+
+    fn to_render_element(
+        &self,
+        location: Point<i32, Logical>,
+        scale: Scale<f64>,
+        alpha: f32,
+        kind: Kind,
+    ) -> Self::RenderElement;
+}
+
+impl ToRenderElement for BakedBuffer<TextureBuffer<GlesTexture>> {
+    type RenderElement = PrimaryGpuTextureRenderElement;
+
+    fn to_render_element(
+        &self,
+        location: Point<i32, Logical>,
+        scale: Scale<f64>,
+        alpha: f32,
+        kind: Kind,
+    ) -> Self::RenderElement {
+        let elem = TextureRenderElement::from_texture_buffer(
+            (location + self.location).to_physical_precise_round(scale),
+            &self.buffer,
+            Some(alpha),
+            self.src,
+            self.dst,
+            kind,
+        );
+        PrimaryGpuTextureRenderElement(elem)
+    }
+}
+
+impl ToRenderElement for BakedBuffer<SolidColorBuffer> {
+    type RenderElement = SolidColorRenderElement;
+
+    fn to_render_element(
+        &self,
+        location: Point<i32, Logical>,
+        scale: Scale<f64>,
+        alpha: f32,
+        kind: Kind,
+    ) -> Self::RenderElement {
+        SolidColorRenderElement::from_buffer(
+            &self.buffer,
+            (location + self.location)
+                .to_physical_precise_round(scale)
+                .to_i32_round(),
+            scale,
+            alpha,
+            kind,
+        )
+    }
+}
+
+pub fn render_to_encompassing_texture(
+    renderer: &mut GlesRenderer,
+    scale: Scale<f64>,
+    transform: Transform,
+    fourcc: Fourcc,
+    elements: &[impl RenderElement<GlesRenderer>],
+) -> anyhow::Result<(GlesTexture, SyncPoint, Rectangle<i32, Physical>)> {
+    let geo = elements
+        .iter()
+        .map(|ele| ele.geometry(scale))
+        .reduce(|a, b| a.merge(b))
+        .unwrap_or_default();
+    let elements = elements.iter().rev().map(|ele| {
+        RelocateRenderElement::from_element(ele, (-geo.loc.x, -geo.loc.y), Relocate::Relative)
+    });
+
+    let (texture, sync_point) =
+        render_to_texture(renderer, geo.size, scale, transform, fourcc, elements)?;
+
+    Ok((texture, sync_point, geo))
+}
+
+pub fn render_to_texture(
+    renderer: &mut GlesRenderer,
+    size: Size<i32, Physical>,
+    scale: Scale<f64>,
+    transform: Transform,
+    fourcc: Fourcc,
+    elements: impl Iterator<Item = impl RenderElement<GlesRenderer>>,
+) -> anyhow::Result<(GlesTexture, SyncPoint)> {
+    let _span = tracy_client::span!();
+
+    let buffer_size = size.to_logical(1).to_buffer(1, Transform::Normal);
+
+    let texture: GlesTexture = renderer
+        .create_buffer(fourcc, buffer_size)
+        .context("error creating texture")?;
+
+    renderer
+        .bind(texture.clone())
+        .context("error binding texture")?;
+
+    let sync_point = render_elements(renderer, size, scale, transform, elements)?;
+    Ok((texture, sync_point))
+}
+
+pub fn render_and_download(
+    renderer: &mut GlesRenderer,
+    size: Size<i32, Physical>,
+    scale: Scale<f64>,
+    transform: Transform,
+    fourcc: Fourcc,
+    elements: impl Iterator<Item = impl RenderElement<GlesRenderer>>,
+) -> anyhow::Result<GlesMapping> {
+    let _span = tracy_client::span!();
+
+    let (_, _) = render_to_texture(renderer, size, scale, transform, fourcc, elements)?;
+
+    let buffer_size = size.to_logical(1).to_buffer(1, Transform::Normal);
+    let mapping = renderer
+        .copy_framebuffer(Rectangle::from_loc_and_size((0, 0), buffer_size), fourcc)
+        .context("error copying framebuffer")?;
+    Ok(mapping)
+}
+
+pub fn render_to_vec(
+    renderer: &mut GlesRenderer,
+    size: Size<i32, Physical>,
+    scale: Scale<f64>,
+    transform: Transform,
+    fourcc: Fourcc,
+    elements: impl Iterator<Item = impl RenderElement<GlesRenderer>>,
+) -> anyhow::Result<Vec<u8>> {
+    let _span = tracy_client::span!();
+
+    let mapping = render_and_download(renderer, size, scale, transform, fourcc, elements)
+        .context("error rendering")?;
+    let copy = renderer
+        .map_texture(&mapping)
+        .context("error mapping texture")?;
+    Ok(copy.to_vec())
+}
+
+#[cfg(feature = "xdp-gnome-screencast")]
+pub fn render_to_dmabuf(
+    renderer: &mut GlesRenderer,
+    dmabuf: smithay::backend::allocator::dmabuf::Dmabuf,
+    size: Size<i32, Physical>,
+    scale: Scale<f64>,
+    transform: Transform,
+    elements: impl Iterator<Item = impl RenderElement<GlesRenderer>>,
+) -> anyhow::Result<SyncPoint> {
+    let _span = tracy_client::span!();
+    renderer.bind(dmabuf).context("error binding texture")?;
+    render_elements(renderer, size, scale, transform, elements)
+}
+
+pub fn render_to_shm(
+    renderer: &mut GlesRenderer,
+    buffer: &WlBuffer,
+    scale: Scale<f64>,
+    transform: Transform,
+    elements: impl Iterator<Item = impl RenderElement<GlesRenderer>>,
+) -> anyhow::Result<()> {
+    let _span = tracy_client::span!();
+
+    let buffer_size = buffer_dimensions(buffer).context("error getting buffer dimensions")?;
+    let size = buffer_size.to_logical(1, Transform::Normal).to_physical(1);
+
+    let mapping =
+        render_and_download(renderer, size, scale, transform, Fourcc::Argb8888, elements)?;
+    let bytes = renderer
+        .map_texture(&mapping)
+        .context("error mapping texture")?;
+
+    shm::with_buffer_contents_mut(buffer, |shm_buffer, shm_len, buffer_data| {
+        ensure!(
+            // The buffer prefers pixels in little endian ...
+            buffer_data.format == wl_shm::Format::Argb8888
+                && buffer_data.stride == size.w * 4
+                && buffer_data.height == size.h
+                && shm_len as i32 == buffer_data.stride * buffer_data.height,
+            "invalid buffer format or size"
+        );
+
+        ensure!(bytes.len() == shm_len, "mapped buffer has wrong length");
+
+        unsafe {
+            let _span = tracy_client::span!("copy_nonoverlapping");
+            ptr::copy_nonoverlapping(bytes.as_ptr(), shm_buffer.cast(), shm_len);
+        }
+
+        Ok(())
+    })
+    .context("expected shm buffer, but didn't get one")?
+}
+
+fn render_elements(
+    renderer: &mut GlesRenderer,
+    size: Size<i32, Physical>,
+    scale: Scale<f64>,
+    transform: Transform,
+    elements: impl Iterator<Item = impl RenderElement<GlesRenderer>>,
+) -> anyhow::Result<SyncPoint> {
+    let transform = transform.invert();
+    let output_rect = Rectangle::from_loc_and_size((0, 0), transform.transform_size(size));
+
+    let mut frame = renderer
+        .render(size, transform)
+        .context("error starting frame")?;
+
+    frame
+        .clear([0., 0., 0., 0.], &[output_rect])
+        .context("error clearing")?;
+
+    for element in elements {
+        let src = element.src();
+        let dst = element.geometry(scale);
+
+        if let Some(mut damage) = output_rect.intersection(dst) {
+            damage.loc -= dst.loc;
+            element
+                .draw(&mut frame, src, dst, &[damage])
+                .context("error drawing element")?;
+        }
+    }
+
+    frame.finish().context("error finishing frame")
+}

src/render_helpers/offscreen.rs

@@ -0,0 +1,216 @@
+use smithay::backend::allocator::Fourcc;
+use smithay::backend::renderer::element::solid::{SolidColorBuffer, SolidColorRenderElement};
+use smithay::backend::renderer::element::texture::{TextureBuffer, TextureRenderElement};
+use smithay::backend::renderer::element::utils::{Relocate, RelocateRenderElement};
+use smithay::backend::renderer::element::{Element, Id, Kind, RenderElement, UnderlyingStorage};
+use smithay::backend::renderer::gles::{GlesError, GlesFrame, GlesRenderer};
+use smithay::backend::renderer::utils::{CommitCounter, DamageSet};
+use smithay::utils::{Buffer, Physical, Rectangle, Scale, Transform};
+
+use super::primary_gpu_texture::PrimaryGpuTextureRenderElement;
+use super::render_to_texture;
+use super::renderer::AsGlesFrame;
+use crate::backend::tty::{TtyFrame, TtyRenderer, TtyRendererError};
+
+/// Renders elements into an off-screen buffer.
+#[derive(Debug)]
+pub struct OffscreenRenderElement {
+    // The texture, if rendering succeeded.
+    texture: Option<PrimaryGpuTextureRenderElement>,
+    // The fallback buffer in case the rendering fails.
+    fallback: SolidColorRenderElement,
+}
+
+impl OffscreenRenderElement {
+    pub fn new(
+        renderer: &mut GlesRenderer,
+        scale: i32,
+        elements: &[impl RenderElement<GlesRenderer>],
+        result_alpha: f32,
+    ) -> Self {
+        let _span = tracy_client::span!("OffscreenRenderElement::new");
+
+        let geo = elements
+            .iter()
+            .map(|ele| ele.geometry(Scale::from(f64::from(scale))))
+            .reduce(|a, b| a.merge(b))
+            .unwrap_or_default();
+        let logical_size = geo.size.to_logical(scale);
+
+        let fallback_buffer = SolidColorBuffer::new(logical_size, [1., 0., 0., 1.]);
+        let fallback = SolidColorRenderElement::from_buffer(
+            &fallback_buffer,
+            geo.loc,
+            Scale::from(scale as f64),
+            result_alpha,
+            Kind::Unspecified,
+        );
+
+        let elements = elements.iter().rev().map(|ele| {
+            RelocateRenderElement::from_element(ele, (-geo.loc.x, -geo.loc.y), Relocate::Relative)
+        });
+
+        match render_to_texture(
+            renderer,
+            geo.size,
+            Scale::from(scale as f64),
+            Transform::Normal,
+            Fourcc::Abgr8888,
+            elements,
+        ) {
+            Ok((texture, _sync_point)) => {
+                let buffer =
+                    TextureBuffer::from_texture(renderer, texture, scale, Transform::Normal, None);
+                let element = TextureRenderElement::from_texture_buffer(
+                    geo.loc.to_f64(),
+                    &buffer,
+                    Some(result_alpha),
+                    None,
+                    None,
+                    Kind::Unspecified,
+                );
+                Self {
+                    texture: Some(PrimaryGpuTextureRenderElement(element)),
+                    fallback,
+                }
+            }
+            Err(err) => {
+                warn!("error off-screening elements: {err:?}");
+                Self {
+                    texture: None,
+                    fallback,
+                }
+            }
+        }
+    }
+}
+
+impl Element for OffscreenRenderElement {
+    fn id(&self) -> &Id {
+        if let Some(texture) = &self.texture {
+            texture.id()
+        } else {
+            self.fallback.id()
+        }
+    }
+
+    fn current_commit(&self) -> CommitCounter {
+        if let Some(texture) = &self.texture {
+            texture.current_commit()
+        } else {
+            self.fallback.current_commit()
+        }
+    }
+
+    fn geometry(&self, scale: Scale<f64>) -> Rectangle<i32, Physical> {
+        if let Some(texture) = &self.texture {
+            texture.geometry(scale)
+        } else {
+            self.fallback.geometry(scale)
+        }
+    }
+
+    fn transform(&self) -> Transform {
+        if let Some(texture) = &self.texture {
+            texture.transform()
+        } else {
+            self.fallback.transform()
+        }
+    }
+
+    fn src(&self) -> Rectangle<f64, Buffer> {
+        if let Some(texture) = &self.texture {
+            texture.src()
+        } else {
+            self.fallback.src()
+        }
+    }
+
+    fn damage_since(
+        &self,
+        scale: Scale<f64>,
+        commit: Option<CommitCounter>,
+    ) -> DamageSet<i32, Physical> {
+        if let Some(texture) = &self.texture {
+            texture.damage_since(scale, commit)
+        } else {
+            self.fallback.damage_since(scale, commit)
+        }
+    }
+
+    fn opaque_regions(&self, scale: Scale<f64>) -> Vec<Rectangle<i32, Physical>> {
+        if let Some(texture) = &self.texture {
+            texture.opaque_regions(scale)
+        } else {
+            self.fallback.opaque_regions(scale)
+        }
+    }
+
+    fn alpha(&self) -> f32 {
+        if let Some(texture) = &self.texture {
+            texture.alpha()
+        } else {
+            self.fallback.alpha()
+        }
+    }
+
+    fn kind(&self) -> Kind {
+        if let Some(texture) = &self.texture {
+            texture.kind()
+        } else {
+            self.fallback.kind()
+        }
+    }
+}
+
+impl RenderElement<GlesRenderer> for OffscreenRenderElement {
+    fn draw(
+        &self,
+        frame: &mut GlesFrame<'_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), GlesError> {
+        let gles_frame = frame.as_gles_frame();
+        if let Some(texture) = &self.texture {
+            RenderElement::<GlesRenderer>::draw(texture, gles_frame, src, dst, damage)?;
+        } else {
+            RenderElement::<GlesRenderer>::draw(&self.fallback, gles_frame, src, dst, damage)?;
+        }
+        Ok(())
+    }
+
+    fn underlying_storage(&self, renderer: &mut GlesRenderer) -> Option<UnderlyingStorage> {
+        if let Some(texture) = &self.texture {
+            texture.underlying_storage(renderer)
+        } else {
+            self.fallback.underlying_storage(renderer)
+        }
+    }
+}
+
+impl<'render> RenderElement<TtyRenderer<'render>> for OffscreenRenderElement {
+    fn draw(
+        &self,
+        frame: &mut TtyFrame<'_, '_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), TtyRendererError<'render>> {
+        let gles_frame = frame.as_gles_frame();
+        if let Some(texture) = &self.texture {
+            RenderElement::<GlesRenderer>::draw(texture, gles_frame, src, dst, damage)?;
+        } else {
+            RenderElement::<GlesRenderer>::draw(&self.fallback, gles_frame, src, dst, damage)?;
+        }
+        Ok(())
+    }
+
+    fn underlying_storage(&self, renderer: &mut TtyRenderer<'render>) -> Option<UnderlyingStorage> {
+        if let Some(texture) = &self.texture {
+            texture.underlying_storage(renderer)
+        } else {
+            self.fallback.underlying_storage(renderer)
+        }
+    }
+}

src/render_helpers/primary_gpu_pixel_shader.rs

@@ -0,0 +1,97 @@
+use smithay::backend::renderer::element::{Element, Id, Kind, RenderElement, UnderlyingStorage};
+use smithay::backend::renderer::gles::element::PixelShaderElement;
+use smithay::backend::renderer::gles::{GlesError, GlesFrame, GlesRenderer};
+use smithay::backend::renderer::utils::{CommitCounter, DamageSet};
+use smithay::utils::{Buffer, Physical, Rectangle, Scale, Transform};
+
+use super::renderer::AsGlesFrame;
+use crate::backend::tty::{TtyFrame, TtyRenderer, TtyRendererError};
+
+/// Wrapper for a pixel shader from the primary GPU for rendering with the primary GPU.
+#[derive(Debug)]
+pub struct PrimaryGpuPixelShaderRenderElement(pub PixelShaderElement);
+
+impl Element for PrimaryGpuPixelShaderRenderElement {
+    fn id(&self) -> &Id {
+        self.0.id()
+    }
+
+    fn current_commit(&self) -> CommitCounter {
+        self.0.current_commit()
+    }
+
+    fn geometry(&self, scale: Scale<f64>) -> Rectangle<i32, Physical> {
+        self.0.geometry(scale)
+    }
+
+    fn transform(&self) -> Transform {
+        self.0.transform()
+    }
+
+    fn src(&self) -> Rectangle<f64, Buffer> {
+        self.0.src()
+    }
+
+    fn damage_since(
+        &self,
+        scale: Scale<f64>,
+        commit: Option<CommitCounter>,
+    ) -> DamageSet<i32, Physical> {
+        self.0.damage_since(scale, commit)
+    }
+
+    fn opaque_regions(&self, scale: Scale<f64>) -> Vec<Rectangle<i32, Physical>> {
+        self.0.opaque_regions(scale)
+    }
+
+    fn alpha(&self) -> f32 {
+        self.0.alpha()
+    }
+
+    fn kind(&self) -> Kind {
+        self.0.kind()
+    }
+}
+
+impl RenderElement<GlesRenderer> for PrimaryGpuPixelShaderRenderElement {
+    fn draw(
+        &self,
+        frame: &mut GlesFrame<'_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), GlesError> {
+        let gles_frame = frame.as_gles_frame();
+        RenderElement::<GlesRenderer>::draw(&self.0, gles_frame, src, dst, damage)?;
+        Ok(())
+    }
+
+    fn underlying_storage(&self, _renderer: &mut GlesRenderer) -> Option<UnderlyingStorage> {
+        // If scanout for things other than Wayland buffers is implemented, this will need to take
+        // the target GPU into account.
+        None
+    }
+}
+
+impl<'render> RenderElement<TtyRenderer<'render>> for PrimaryGpuPixelShaderRenderElement {
+    fn draw(
+        &self,
+        frame: &mut TtyFrame<'_, '_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), TtyRendererError<'render>> {
+        let gles_frame = frame.as_gles_frame();
+        RenderElement::<GlesRenderer>::draw(&self.0, gles_frame, src, dst, damage)?;
+        Ok(())
+    }
+
+    fn underlying_storage(
+        &self,
+        _renderer: &mut TtyRenderer<'render>,
+    ) -> Option<UnderlyingStorage> {
+        // If scanout for things other than Wayland buffers is implemented, this will need to take
+        // the target GPU into account.
+        None
+    }
+}

src/render_helpers/primary_gpu_pixel_shader_with_textures.rs

@@ -0,0 +1,430 @@
+use std::collections::HashMap;
+use std::ffi::{CStr, CString};
+use std::rc::Rc;
+
+use glam::{Mat3, Vec2};
+use smithay::backend::renderer::element::{Element, Id, Kind, RenderElement, UnderlyingStorage};
+use smithay::backend::renderer::gles::{
+    ffi, link_program, Capability, GlesError, GlesFrame, GlesRenderer, GlesTexture, Uniform,
+    UniformDesc, UniformName,
+};
+use smithay::backend::renderer::utils::CommitCounter;
+use smithay::utils::{Buffer, Logical, Physical, Rectangle, Scale, Size};
+
+use super::renderer::AsGlesFrame;
+use super::resources::Resources;
+use crate::backend::tty::{TtyFrame, TtyRenderer, TtyRendererError};
+
+/// Wrapper for a pixel shader from the primary GPU for rendering with the primary GPU.
+///
+/// The shader accepts textures as input.
+#[derive(Debug)]
+pub struct PrimaryGpuPixelShaderWithTexturesRenderElement {
+    shader: PixelWithTexturesProgram,
+    textures: HashMap<String, GlesTexture>,
+    id: Id,
+    commit_counter: CommitCounter,
+    area: Rectangle<i32, Logical>,
+    size: Size<f64, Buffer>,
+    opaque_regions: Vec<Rectangle<i32, Logical>>,
+    alpha: f32,
+    additional_uniforms: Vec<Uniform<'static>>,
+    kind: Kind,
+}
+
+#[derive(Debug, Clone)]
+pub struct PixelWithTexturesProgram(Rc<PixelWithTexturesProgramInner>);
+
+#[derive(Debug)]
+struct PixelWithTexturesProgramInner {
+    program: ffi::types::GLuint,
+    uniform_tex_matrix: ffi::types::GLint,
+    uniform_matrix: ffi::types::GLint,
+    uniform_size: ffi::types::GLint,
+    uniform_alpha: ffi::types::GLint,
+    attrib_vert: ffi::types::GLint,
+    attrib_vert_position: ffi::types::GLint,
+    additional_uniforms: HashMap<String, UniformDesc>,
+    texture_uniforms: HashMap<String, ffi::types::GLint>,
+}
+
+unsafe fn compile_program(
+    gl: &ffi::Gles2,
+    src: &str,
+    additional_uniforms: &[UniformName<'_>],
+    texture_uniforms: &[&str],
+    // destruction_callback_sender: Sender<CleanupResource>,
+) -> Result<PixelWithTexturesProgram, GlesError> {
+    let shader = src;
+
+    let program = unsafe { link_program(gl, include_str!("shaders/texture.vert"), shader)? };
+
+    let vert = CStr::from_bytes_with_nul(b"vert\0").expect("NULL terminated");
+    let vert_position = CStr::from_bytes_with_nul(b"vert_position\0").expect("NULL terminated");
+    let matrix = CStr::from_bytes_with_nul(b"matrix\0").expect("NULL terminated");
+    let tex_matrix = CStr::from_bytes_with_nul(b"tex_matrix\0").expect("NULL terminated");
+    let size = CStr::from_bytes_with_nul(b"size\0").expect("NULL terminated");
+    let alpha = CStr::from_bytes_with_nul(b"alpha\0").expect("NULL terminated");
+
+    Ok(PixelWithTexturesProgram(Rc::new(
+        PixelWithTexturesProgramInner {
+            program,
+            uniform_matrix: gl
+                .GetUniformLocation(program, matrix.as_ptr() as *const ffi::types::GLchar),
+            uniform_tex_matrix: gl
+                .GetUniformLocation(program, tex_matrix.as_ptr() as *const ffi::types::GLchar),
+            uniform_size: gl
+                .GetUniformLocation(program, size.as_ptr() as *const ffi::types::GLchar),
+            uniform_alpha: gl
+                .GetUniformLocation(program, alpha.as_ptr() as *const ffi::types::GLchar),
+            attrib_vert: gl.GetAttribLocation(program, vert.as_ptr() as *const ffi::types::GLchar),
+            attrib_vert_position: gl
+                .GetAttribLocation(program, vert_position.as_ptr() as *const ffi::types::GLchar),
+            additional_uniforms: additional_uniforms
+                .iter()
+                .map(|uniform| {
+                    let name =
+                        CString::new(uniform.name.as_bytes()).expect("Interior null in name");
+                    let location =
+                        gl.GetUniformLocation(program, name.as_ptr() as *const ffi::types::GLchar);
+                    (
+                        uniform.name.clone().into_owned(),
+                        UniformDesc {
+                            location,
+                            type_: uniform.type_,
+                        },
+                    )
+                })
+                .collect(),
+            texture_uniforms: texture_uniforms
+                .iter()
+                .map(|name_| {
+                    let name = CString::new(name_.as_bytes()).expect("Interior null in name");
+                    let location =
+                        gl.GetUniformLocation(program, name.as_ptr() as *const ffi::types::GLchar);
+                    (name_.to_string(), location)
+                })
+                .collect(),
+        },
+    )))
+}
+
+impl PixelWithTexturesProgram {
+    pub fn compile(
+        renderer: &mut GlesRenderer,
+        src: &str,
+        additional_uniforms: &[UniformName<'_>],
+        texture_uniforms: &[&str],
+    ) -> Result<Self, GlesError> {
+        renderer.with_context(move |gl| unsafe {
+            compile_program(gl, src, additional_uniforms, texture_uniforms)
+        })?
+    }
+}
+
+impl PrimaryGpuPixelShaderWithTexturesRenderElement {
+    #[allow(clippy::too_many_arguments)]
+    pub fn new(
+        shader: PixelWithTexturesProgram,
+        textures: HashMap<String, GlesTexture>,
+        area: Rectangle<i32, Logical>,
+        size: Size<f64, Buffer>,
+        opaque_regions: Option<Vec<Rectangle<i32, Logical>>>,
+        alpha: f32,
+        additional_uniforms: Vec<Uniform<'_>>,
+        kind: Kind,
+    ) -> Self {
+        Self {
+            shader,
+            textures,
+            id: Id::new(),
+            commit_counter: CommitCounter::default(),
+            area,
+            size,
+            opaque_regions: opaque_regions.unwrap_or_default(),
+            alpha,
+            additional_uniforms: additional_uniforms
+                .into_iter()
+                .map(|u| u.into_owned())
+                .collect(),
+            kind,
+        }
+    }
+}
+
+impl Element for PrimaryGpuPixelShaderWithTexturesRenderElement {
+    fn id(&self) -> &Id {
+        &self.id
+    }
+
+    fn current_commit(&self) -> CommitCounter {
+        self.commit_counter
+    }
+
+    fn src(&self) -> Rectangle<f64, Buffer> {
+        Rectangle::from_loc_and_size((0., 0.), self.size.to_f64())
+    }
+
+    fn geometry(&self, scale: Scale<f64>) -> Rectangle<i32, Physical> {
+        self.area.to_physical_precise_round(scale)
+    }
+
+    fn opaque_regions(&self, scale: Scale<f64>) -> Vec<Rectangle<i32, Physical>> {
+        self.opaque_regions
+            .iter()
+            .map(|region| region.to_physical_precise_round(scale))
+            .collect()
+    }
+
+    fn alpha(&self) -> f32 {
+        1.0
+    }
+
+    fn kind(&self) -> Kind {
+        self.kind
+    }
+}
+
+impl RenderElement<GlesRenderer> for PrimaryGpuPixelShaderWithTexturesRenderElement {
+    fn draw(
+        &self,
+        frame: &mut GlesFrame<'_>,
+        src: Rectangle<f64, Buffer>,
+        dest: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), GlesError> {
+        let frame = frame.as_gles_frame();
+
+        let Some(resources) = Resources::get(frame) else {
+            return Ok(());
+        };
+        let mut resources = resources.borrow_mut();
+
+        let supports_instancing = frame.capabilities().contains(&Capability::Instancing);
+
+        // prepare the vertices
+        resources.vertices.clear();
+        if supports_instancing {
+            resources.vertices.extend(damage.iter().flat_map(|rect| {
+                let dest_size = dest.size;
+
+                let rect_constrained_loc = rect
+                    .loc
+                    .constrain(Rectangle::from_extemities((0, 0), dest_size.to_point()));
+                let rect_clamped_size = rect.size.clamp(
+                    (0, 0),
+                    (dest_size.to_point() - rect_constrained_loc).to_size(),
+                );
+
+                let rect = Rectangle::from_loc_and_size(rect_constrained_loc, rect_clamped_size);
+                [
+                    rect.loc.x as f32,
+                    rect.loc.y as f32,
+                    rect.size.w as f32,
+                    rect.size.h as f32,
+                ]
+            }));
+        } else {
+            resources.vertices.extend(damage.iter().flat_map(|rect| {
+                let dest_size = dest.size;
+
+                let rect_constrained_loc = rect
+                    .loc
+                    .constrain(Rectangle::from_extemities((0, 0), dest_size.to_point()));
+                let rect_clamped_size = rect.size.clamp(
+                    (0, 0),
+                    (dest_size.to_point() - rect_constrained_loc).to_size(),
+                );
+
+                let rect = Rectangle::from_loc_and_size(rect_constrained_loc, rect_clamped_size);
+                // Add the 4 f32s per damage rectangle for each of the 6 vertices.
+                (0..6).flat_map(move |_| {
+                    [
+                        rect.loc.x as f32,
+                        rect.loc.y as f32,
+                        rect.size.w as f32,
+                        rect.size.h as f32,
+                    ]
+                })
+            }));
+        }
+
+        if resources.vertices.is_empty() {
+            return Ok(());
+        }
+
+        // dest position and scale
+        let mut matrix = Mat3::from_translation(Vec2::new(dest.loc.x as f32, dest.loc.y as f32));
+
+        let scale = src.size.to_f64() / dest.size.to_f64();
+        let tex_matrix = Mat3::from_scale(Vec2::new(scale.x as f32, scale.y as f32));
+        let tex_matrix =
+            Mat3::from_translation(Vec2::new(src.loc.x as f32, src.loc.y as f32)) * tex_matrix;
+        let tex_matrix = Mat3::from_scale(Vec2::new(
+            (1.0f64 / self.size.w) as f32,
+            (1.0f64 / self.size.h) as f32,
+        )) * tex_matrix;
+
+        //apply output transformation
+        matrix = Mat3::from_cols_array(frame.projection()) * matrix;
+
+        let program = &self.shader.0;
+
+        // render
+        frame.with_context(move |gl| -> Result<(), GlesError> {
+            unsafe {
+                for (i, texture) in self.textures.values().enumerate() {
+                    gl.ActiveTexture(ffi::TEXTURE0 + i as u32);
+                    gl.BindTexture(ffi::TEXTURE_2D, texture.tex_id());
+                    gl.TexParameteri(ffi::TEXTURE_2D, ffi::TEXTURE_MIN_FILTER, ffi::LINEAR as i32);
+                    gl.TexParameteri(ffi::TEXTURE_2D, ffi::TEXTURE_MAG_FILTER, ffi::LINEAR as i32);
+                    gl.TexParameteri(
+                        ffi::TEXTURE_2D,
+                        ffi::TEXTURE_WRAP_S,
+                        ffi::CLAMP_TO_BORDER as i32,
+                    );
+                    gl.TexParameteri(
+                        ffi::TEXTURE_2D,
+                        ffi::TEXTURE_WRAP_T,
+                        ffi::CLAMP_TO_BORDER as i32,
+                    );
+                }
+
+                gl.UseProgram(program.program);
+
+                for (i, name) in self.textures.keys().enumerate() {
+                    gl.Uniform1i(program.texture_uniforms[name], i as i32);
+                }
+
+                gl.UniformMatrix3fv(
+                    program.uniform_matrix,
+                    1,
+                    ffi::FALSE,
+                    matrix.as_ref().as_ptr(),
+                );
+                gl.UniformMatrix3fv(
+                    program.uniform_tex_matrix,
+                    1,
+                    ffi::FALSE,
+                    tex_matrix.as_ref().as_ptr(),
+                );
+                gl.Uniform2f(program.uniform_size, dest.size.w as f32, dest.size.h as f32);
+                gl.Uniform1f(program.uniform_alpha, self.alpha);
+
+                for uniform in &self.additional_uniforms {
+                    let desc =
+                        program
+                            .additional_uniforms
+                            .get(&*uniform.name)
+                            .ok_or_else(|| {
+                                GlesError::UnknownUniform(uniform.name.clone().into_owned())
+                            })?;
+                    uniform.value.set(gl, desc)?;
+                }
+
+                gl.EnableVertexAttribArray(program.attrib_vert as u32);
+                gl.BindBuffer(ffi::ARRAY_BUFFER, resources.vbos[0]);
+                gl.VertexAttribPointer(
+                    program.attrib_vert as u32,
+                    2,
+                    ffi::FLOAT,
+                    ffi::FALSE,
+                    0,
+                    std::ptr::null(),
+                );
+
+                // vert_position
+                gl.EnableVertexAttribArray(program.attrib_vert_position as u32);
+                gl.BindBuffer(ffi::ARRAY_BUFFER, resources.vbos[1]);
+                gl.BufferData(
+                    ffi::ARRAY_BUFFER,
+                    (std::mem::size_of::<ffi::types::GLfloat>() * resources.vertices.len())
+                        as isize,
+                    resources.vertices.as_ptr() as *const _,
+                    ffi::STREAM_DRAW,
+                );
+
+                gl.VertexAttribPointer(
+                    program.attrib_vert_position as u32,
+                    4,
+                    ffi::FLOAT,
+                    ffi::FALSE,
+                    0,
+                    std::ptr::null(),
+                );
+
+                let damage_len = damage.len() as i32;
+                if supports_instancing {
+                    gl.VertexAttribDivisor(program.attrib_vert as u32, 0);
+                    gl.VertexAttribDivisor(program.attrib_vert_position as u32, 1);
+                    gl.DrawArraysInstanced(ffi::TRIANGLE_STRIP, 0, 4, damage_len);
+                } else {
+                    // When we have more than 10 rectangles, draw them in batches of 10.
+                    for i in 0..(damage_len - 1) / 10 {
+                        gl.DrawArrays(ffi::TRIANGLES, 0, 6);
+
+                        // Set damage pointer to the next 10 rectangles.
+                        let offset =
+                            (i + 1) as usize * 6 * 4 * std::mem::size_of::<ffi::types::GLfloat>();
+                        gl.VertexAttribPointer(
+                            program.attrib_vert_position as u32,
+                            4,
+                            ffi::FLOAT,
+                            ffi::FALSE,
+                            0,
+                            offset as *const _,
+                        );
+                    }
+
+                    // Draw the up to 10 remaining rectangles.
+                    let count = ((damage_len - 1) % 10 + 1) * 6;
+                    gl.DrawArrays(ffi::TRIANGLES, 0, count);
+                }
+
+                gl.BindBuffer(ffi::ARRAY_BUFFER, 0);
+                gl.BindTexture(ffi::TEXTURE_2D, 0);
+                gl.ActiveTexture(ffi::TEXTURE0);
+                gl.BindTexture(ffi::TEXTURE_2D, 0);
+                gl.DisableVertexAttribArray(program.attrib_vert as u32);
+                gl.DisableVertexAttribArray(program.attrib_vert_position as u32);
+            }
+
+            Ok(())
+        })??;
+
+        Ok(())
+    }
+
+    fn underlying_storage(&self, _renderer: &mut GlesRenderer) -> Option<UnderlyingStorage> {
+        // If scanout for things other than Wayland buffers is implemented, this will need to take
+        // the target GPU into account.
+        None
+    }
+}
+
+impl<'render> RenderElement<TtyRenderer<'render>>
+    for PrimaryGpuPixelShaderWithTexturesRenderElement
+{
+    fn draw(
+        &self,
+        frame: &mut TtyFrame<'_, '_>,
+        src: Rectangle<f64, Buffer>,
+        dst: Rectangle<i32, Physical>,
+        damage: &[Rectangle<i32, Physical>],
+    ) -> Result<(), TtyRendererError<'render>> {
+        let frame = frame.as_gles_frame();
+
+        RenderElement::<GlesRenderer>::draw(self, frame, src, dst, damage)?;
+
+        Ok(())
+    }
+
+    fn underlying_storage(
+        &self,
+        _renderer: &mut TtyRenderer<'render>,
+    ) -> Option<UnderlyingStorage> {
+        // If scanout for things other than Wayland buffers is implemented, this will need to take
+        // the target GPU into account.
+        None
+    }
+}

src/render_helpers/primary_gpu_texture.rs

@@ -1,81 +1,12 @@
-use smithay::backend::allocator::dmabuf::Dmabuf;
 use smithay::backend::renderer::element::texture::TextureRenderElement;
 use smithay::backend::renderer::element::{Element, Id, Kind, RenderElement, UnderlyingStorage};
 use smithay::backend::renderer::gles::{GlesError, GlesFrame, GlesRenderer, GlesTexture};
-use smithay::backend::renderer::utils::CommitCounter;
+use smithay::backend::renderer::utils::{CommitCounter, DamageSet};
-use smithay::backend::renderer::{
-    Bind, ExportMem, ImportAll, ImportMem, Offscreen, Renderer, Texture,
-};
 use smithay::utils::{Buffer, Physical, Rectangle, Scale, Transform};
 
+use super::renderer::AsGlesFrame;
 use crate::backend::tty::{TtyFrame, TtyRenderer, TtyRendererError};
 
-/// Trait with our main renderer requirements to save on the typing.
-pub trait NiriRenderer:
-    ImportAll
-    + ImportMem
-    + ExportMem
-    + Bind<Dmabuf>
-    + Offscreen<GlesTexture>
-    + Renderer<TextureId = Self::NiriTextureId, Error = Self::NiriError>
-    + AsGlesRenderer
-{
-    // Associated types to work around the instability of associated type bounds.
-    type NiriTextureId: Texture + Clone + 'static;
-    type NiriError: std::error::Error
-        + Send
-        + Sync
-        + From<<GlesRenderer as Renderer>::Error>
-        + 'static;
-}
-
-impl<R> NiriRenderer for R
-where
-    R: ImportAll + ImportMem + ExportMem + Bind<Dmabuf> + Offscreen<GlesTexture> + AsGlesRenderer,
-    R::TextureId: Texture + Clone + 'static,
-    R::Error: std::error::Error + Send + Sync + From<<GlesRenderer as Renderer>::Error> + 'static,
-{
-    type NiriTextureId = R::TextureId;
-    type NiriError = R::Error;
-}
-
-/// Trait for getting the underlying `GlesRenderer`.
-pub trait AsGlesRenderer {
-    fn as_gles_renderer(&mut self) -> &mut GlesRenderer;
-}
-
-impl AsGlesRenderer for GlesRenderer {
-    fn as_gles_renderer(&mut self) -> &mut GlesRenderer {
-        self
-    }
-}
-
-impl<'render, 'alloc> AsGlesRenderer for TtyRenderer<'render, 'alloc> {
-    fn as_gles_renderer(&mut self) -> &mut GlesRenderer {
-        self.as_mut()
-    }
-}
-
-/// Trait for getting the underlying `GlesFrame`.
-pub trait AsGlesFrame<'frame>
-where
-    Self: 'frame,
-{
-    fn as_gles_frame(&mut self) -> &mut GlesFrame<'frame>;
-}
-
-impl<'frame> AsGlesFrame<'frame> for GlesFrame<'frame> {
-    fn as_gles_frame(&mut self) -> &mut GlesFrame<'frame> {
-        self
-    }
-}
-
-impl<'render, 'alloc, 'frame> AsGlesFrame<'frame> for TtyFrame<'render, 'alloc, 'frame> {
-    fn as_gles_frame(&mut self) -> &mut GlesFrame<'frame> {
-        self.as_mut()
-    }
-}
-
 /// Wrapper for a texture from the primary GPU for rendering with the primary GPU.
 #[derive(Debug)]
 pub struct PrimaryGpuTextureRenderElement(pub TextureRenderElement<GlesTexture>);
@@ -105,7 +36,7 @@ impl Element for PrimaryGpuTextureRenderElement {
         &self,
         scale: Scale<f64>,
         commit: Option<CommitCounter>,
-    ) -> Vec<Rectangle<i32, Physical>> {
+    ) -> DamageSet<i32, Physical> {
         self.0.damage_since(scale, commit)
     }
 
@@ -142,16 +73,14 @@ impl RenderElement<GlesRenderer> for PrimaryGpuTextureRenderElement {
     }
 }
 
-impl<'render, 'alloc> RenderElement<TtyRenderer<'render, 'alloc>>
+impl<'render> RenderElement<TtyRenderer<'render>> for PrimaryGpuTextureRenderElement {
-    for PrimaryGpuTextureRenderElement
-{
     fn draw(
         &self,
-        frame: &mut TtyFrame<'_, '_, '_>,
+        frame: &mut TtyFrame<'_, '_>,
         src: Rectangle<f64, Buffer>,
         dst: Rectangle<i32, Physical>,
         damage: &[Rectangle<i32, Physical>],
-    ) -> Result<(), TtyRendererError<'render, 'alloc>> {
+    ) -> Result<(), TtyRendererError<'render>> {
         let gles_frame = frame.as_gles_frame();
         RenderElement::<GlesRenderer>::draw(&self.0, gles_frame, src, dst, damage)?;
         Ok(())
@@ -159,7 +88,7 @@ impl<'render, 'alloc> RenderElement<TtyRenderer<'render, 'alloc>>
 
     fn underlying_storage(
         &self,
-        _renderer: &mut TtyRenderer<'render, 'alloc>,
+        _renderer: &mut TtyRenderer<'render>,
     ) -> Option<UnderlyingStorage> {
         // If scanout for things other than Wayland buffers is implemented, this will need to take
         // the target GPU into account.

src/render_helpers/render_elements.rs

@@ -0,0 +1,148 @@
+// We need to implement RenderElement manually due to AsGlesFrame requirement.
+// This macro does it for us.
+#[macro_export]
+macro_rules! niri_render_elements {
+    // The two callable variants: with <R> and without <R>. They include From impls because nested
+    // repetitions ($type and $variant with + and $R with ?) don't work properly.
+    ($name:ident<R> => { $($variant:ident = $type:ty),+ $(,)? }) => {
+        $crate::niri_render_elements!(@impl $name () ($name<R>) => { $($variant = $type),+ });
+
+        $(impl<R: $crate::render_helpers::renderer::NiriRenderer> From<$type> for $name<R> {
+            fn from(x: $type) -> Self {
+                Self::$variant(x)
+            }
+        })+
+    };
+
+    ($name:ident => { $($variant:ident = $type:ty),+ $(,)? }) => {
+        $crate::niri_render_elements!(@impl $name ($name) () => { $($variant = $type),+ });
+
+        $(impl From<$type> for $name {
+            fn from(x: $type) -> Self {
+                Self::$variant(x)
+            }
+        })+
+    };
+
+    // The internal variant that generates most of the code. $name_no_R and $name_R are necessary
+    // for the impl RenderElement<SomeRenderer> for $name<SomeRenderer>: since $R does not appear
+    // in this line, we cannot condition based on $R like elsewhere, so we condition on duplicate
+    // names instead. Like this: $($name_R<SomeRenderer>)? $($name_no_R)? so only one is chosen.
+    (@impl $name:ident ($($name_no_R:ident)?) ($($name_R:ident<$R:ident>)?) => { $($variant:ident = $type:ty),+ }) => {
+        #[derive(Debug)]
+        pub enum $name$(<$R: $crate::render_helpers::renderer::NiriRenderer>)? {
+            $($variant($type)),+
+        }
+
+        impl$(<$R: $crate::render_helpers::renderer::NiriRenderer>)? smithay::backend::renderer::element::Element for $name$(<$R>)? {
+            fn id(&self) -> &smithay::backend::renderer::element::Id {
+                match self {
+                    $($name::$variant(elem) => elem.id()),+
+                }
+            }
+
+            fn current_commit(&self) -> smithay::backend::renderer::utils::CommitCounter {
+                match self {
+                    $($name::$variant(elem) => elem.current_commit()),+
+                }
+            }
+
+            fn geometry(&self, scale: smithay::utils::Scale<f64>) -> smithay::utils::Rectangle<i32, smithay::utils::Physical> {
+                match self {
+                    $($name::$variant(elem) => elem.geometry(scale)),+
+                }
+            }
+
+            fn transform(&self) -> smithay::utils::Transform {
+                match self {
+                    $($name::$variant(elem) => elem.transform()),+
+                }
+            }
+
+            fn src(&self) -> smithay::utils::Rectangle<f64, smithay::utils::Buffer> {
+                match self {
+                    $($name::$variant(elem) => elem.src()),+
+                }
+            }
+
+            fn damage_since(
+                &self,
+                scale: smithay::utils::Scale<f64>,
+                commit: Option<smithay::backend::renderer::utils::CommitCounter>,
+            ) -> smithay::backend::renderer::utils::DamageSet<i32, smithay::utils::Physical> {
+                match self {
+                    $($name::$variant(elem) => elem.damage_since(scale, commit)),+
+                }
+            }
+
+            fn opaque_regions(&self, scale: smithay::utils::Scale<f64>) -> Vec<smithay::utils::Rectangle<i32, smithay::utils::Physical>> {
+                match self {
+                    $($name::$variant(elem) => elem.opaque_regions(scale)),+
+                }
+            }
+
+            fn alpha(&self) -> f32 {
+                match self {
+                    $($name::$variant(elem) => elem.alpha()),+
+                }
+            }
+
+            fn kind(&self) -> smithay::backend::renderer::element::Kind {
+                match self {
+                    $($name::$variant(elem) => elem.kind()),+
+                }
+            }
+        }
+
+        impl smithay::backend::renderer::element::RenderElement<smithay::backend::renderer::gles::GlesRenderer>
+            for $($name_R<smithay::backend::renderer::gles::GlesRenderer>)? $($name_no_R)?
+        {
+            fn draw(
+                &self,
+                frame: &mut smithay::backend::renderer::gles::GlesFrame<'_>,
+                src: smithay::utils::Rectangle<f64, smithay::utils::Buffer>,
+                dst: smithay::utils::Rectangle<i32, smithay::utils::Physical>,
+                damage: &[smithay::utils::Rectangle<i32, smithay::utils::Physical>],
+            ) -> Result<(), smithay::backend::renderer::gles::GlesError> {
+                match self {
+                    $($name::$variant(elem) => {
+                        smithay::backend::renderer::element::RenderElement::<smithay::backend::renderer::gles::GlesRenderer>::draw(elem, frame, src, dst, damage)
+                    })+
+                }
+            }
+
+            fn underlying_storage(&self, renderer: &mut smithay::backend::renderer::gles::GlesRenderer) -> Option<smithay::backend::renderer::element::UnderlyingStorage> {
+                match self {
+                    $($name::$variant(elem) => elem.underlying_storage(renderer)),+
+                }
+            }
+        }
+
+        impl<'render> smithay::backend::renderer::element::RenderElement<$crate::backend::tty::TtyRenderer<'render>>
+            for $($name_R<$crate::backend::tty::TtyRenderer<'render>>)? $($name_no_R)?
+        {
+            fn draw(
+                &self,
+                frame: &mut $crate::backend::tty::TtyFrame<'render, '_>,
+                src: smithay::utils::Rectangle<f64, smithay::utils::Buffer>,
+                dst: smithay::utils::Rectangle<i32, smithay::utils::Physical>,
+                damage: &[smithay::utils::Rectangle<i32, smithay::utils::Physical>],
+            ) -> Result<(), $crate::backend::tty::TtyRendererError<'render>> {
+                match self {
+                    $($name::$variant(elem) => {
+                        smithay::backend::renderer::element::RenderElement::<$crate::backend::tty::TtyRenderer<'render>>::draw(elem, frame, src, dst, damage)
+                    })+
+                }
+            }
+
+            fn underlying_storage(
+                &self,
+                renderer: &mut $crate::backend::tty::TtyRenderer<'render>,
+            ) -> Option<smithay::backend::renderer::element::UnderlyingStorage> {
+                match self {
+                    $($name::$variant(elem) => elem.underlying_storage(renderer)),+
+                }
+            }
+        }
+    };
+}

src/render_helpers/renderer.rs

@@ -0,0 +1,73 @@
+use smithay::backend::allocator::dmabuf::Dmabuf;
+use smithay::backend::renderer::gles::{GlesFrame, GlesRenderer, GlesTexture};
+use smithay::backend::renderer::{
+    Bind, ExportMem, ImportAll, ImportMem, Offscreen, Renderer, Texture,
+};
+
+use crate::backend::tty::{TtyFrame, TtyRenderer};
+
+/// Trait with our main renderer requirements to save on the typing.
+pub trait NiriRenderer:
+    ImportAll
+    + ImportMem
+    + ExportMem
+    + Bind<Dmabuf>
+    + Offscreen<GlesTexture>
+    + Renderer<TextureId = Self::NiriTextureId, Error = Self::NiriError>
+    + AsGlesRenderer
+{
+    // Associated types to work around the instability of associated type bounds.
+    type NiriTextureId: Texture + Clone + 'static;
+    type NiriError: std::error::Error
+        + Send
+        + Sync
+        + From<<GlesRenderer as Renderer>::Error>
+        + 'static;
+}
+
+impl<R> NiriRenderer for R
+where
+    R: ImportAll + ImportMem + ExportMem + Bind<Dmabuf> + Offscreen<GlesTexture> + AsGlesRenderer,
+    R::TextureId: Texture + Clone + 'static,
+    R::Error: std::error::Error + Send + Sync + From<<GlesRenderer as Renderer>::Error> + 'static,
+{
+    type NiriTextureId = R::TextureId;
+    type NiriError = R::Error;
+}
+
+/// Trait for getting the underlying `GlesRenderer`.
+pub trait AsGlesRenderer {
+    fn as_gles_renderer(&mut self) -> &mut GlesRenderer;
+}
+
+impl AsGlesRenderer for GlesRenderer {
+    fn as_gles_renderer(&mut self) -> &mut GlesRenderer {
+        self
+    }
+}
+
+impl<'render> AsGlesRenderer for TtyRenderer<'render> {
+    fn as_gles_renderer(&mut self) -> &mut GlesRenderer {
+        self.as_mut()
+    }
+}
+
+/// Trait for getting the underlying `GlesFrame`.
+pub trait AsGlesFrame<'frame>
+where
+    Self: 'frame,
+{
+    fn as_gles_frame(&mut self) -> &mut GlesFrame<'frame>;
+}
+
+impl<'frame> AsGlesFrame<'frame> for GlesFrame<'frame> {
+    fn as_gles_frame(&mut self) -> &mut GlesFrame<'frame> {
+        self
+    }
+}
+
+impl<'render, 'frame> AsGlesFrame<'frame> for TtyFrame<'render, 'frame> {
+    fn as_gles_frame(&mut self) -> &mut GlesFrame<'frame> {
+        self.as_mut()
+    }
+}

src/render_helpers/resources.rs

@@ -0,0 +1,106 @@
+use std::cell::RefCell;
+use std::rc::Rc;
+
+use smithay::backend::renderer::gles::{ffi, Capability, GlesError, GlesFrame, GlesRenderer};
+
+pub struct Resources {
+    pub vertices: Vec<f32>,
+    pub vbos: [ffi::types::GLuint; 2],
+}
+
+static INSTANCED_VERTS: [ffi::types::GLfloat; 8] = [
+    1.0, 0.0, // top right
+    0.0, 0.0, // top left
+    1.0, 1.0, // bottom right
+    0.0, 1.0, // bottom left
+];
+
+/// Vertices for rendering individual triangles.
+const MAX_RECTS_PER_DRAW: usize = 10;
+const TRIANGLE_VERTS: [ffi::types::GLfloat; 12 * MAX_RECTS_PER_DRAW] = triangle_verts();
+const fn triangle_verts() -> [ffi::types::GLfloat; 12 * MAX_RECTS_PER_DRAW] {
+    let mut verts = [0.; 12 * MAX_RECTS_PER_DRAW];
+    let mut i = 0;
+    loop {
+        // Top Left.
+        verts[i * 12] = 0.0;
+        verts[i * 12 + 1] = 0.0;
+
+        // Bottom left.
+        verts[i * 12 + 2] = 0.0;
+        verts[i * 12 + 3] = 1.0;
+
+        // Bottom right.
+        verts[i * 12 + 4] = 1.0;
+        verts[i * 12 + 5] = 1.0;
+
+        // Top left.
+        verts[i * 12 + 6] = 0.0;
+        verts[i * 12 + 7] = 0.0;
+
+        // Bottom right.
+        verts[i * 12 + 8] = 1.0;
+        verts[i * 12 + 9] = 1.0;
+
+        // Top right.
+        verts[i * 12 + 10] = 1.0;
+        verts[i * 12 + 11] = 0.0;
+
+        i += 1;
+        if i == MAX_RECTS_PER_DRAW {
+            break;
+        }
+    }
+    verts
+}
+
+impl Resources {
+    fn create(renderer: &mut GlesRenderer) -> Result<Self, GlesError> {
+        let _span = tracy_client::span!("Resources::init");
+
+        let supports_instancing = renderer.capabilities().contains(&Capability::Instancing);
+        renderer.with_context(|gl| unsafe {
+            let vertices: &[ffi::types::GLfloat] = if supports_instancing {
+                &INSTANCED_VERTS
+            } else {
+                &TRIANGLE_VERTS
+            };
+
+            let mut vbos = [0; 2];
+            gl.GenBuffers(vbos.len() as i32, vbos.as_mut_ptr());
+            gl.BindBuffer(ffi::ARRAY_BUFFER, vbos[0]);
+            gl.BufferData(
+                ffi::ARRAY_BUFFER,
+                std::mem::size_of_val(vertices) as isize,
+                vertices.as_ptr() as *const _,
+                ffi::STATIC_DRAW,
+            );
+
+            gl.BindBuffer(ffi::ARRAY_BUFFER, 0);
+
+            Self {
+                vertices: vec![],
+                vbos,
+            }
+        })
+    }
+
+    pub fn get(frame: &mut GlesFrame) -> Option<Rc<RefCell<Self>>> {
+        let data = frame.egl_context().user_data();
+        data.get().cloned()
+    }
+}
+
+pub fn init(renderer: &mut GlesRenderer) {
+    match Resources::create(renderer) {
+        Ok(resources) => {
+            let data = renderer.egl_context().user_data();
+            if !data.insert_if_missing(|| Rc::new(RefCell::new(resources))) {
+                error!("resources were already initialized");
+            }
+        }
+        Err(err) => {
+            warn!("error creating resources for rendering: {err:?}");
+        }
+    }
+}

src/render_helpers/shaders/crossfade.frag

@@ -0,0 +1,31 @@
+#version 100
+
+precision mediump float;
+
+uniform sampler2D tex_from;
+uniform vec2 tex_from_loc;
+uniform vec2 tex_from_size;
+
+uniform sampler2D tex_to;
+uniform vec2 tex_to_loc;
+uniform vec2 tex_to_size;
+
+uniform float alpha;
+uniform float amount;
+
+uniform vec2 size;
+varying vec2 v_coords;
+
+void main() {
+    vec2 coords_from = (v_coords - tex_from_loc) / tex_from_size;
+    vec2 coords_to = (v_coords - tex_to_loc) / tex_to_size;
+
+    vec4 color_from = texture2D(tex_from, coords_from);
+    vec4 color_to = texture2D(tex_to, coords_to);
+
+    vec4 color = mix(color_from, color_to, amount);
+    color = color * alpha;
+
+    gl_FragColor = color;
+}
+

src/render_helpers/shaders/gradient_border.frag

@@ -0,0 +1,35 @@
+precision mediump float;
+uniform float alpha;
+#if defined(DEBUG_FLAGS)
+uniform float tint;
+#endif
+uniform vec2 size;
+varying vec2 v_coords;
+
+uniform vec4 color_from;
+uniform vec4 color_to;
+uniform vec2 grad_offset;
+uniform float grad_width;
+uniform vec2 grad_vec;
+
+void main() {
+    vec2 coords = v_coords * size + grad_offset;
+
+    if ((grad_vec.x < 0.0 && 0.0 <= grad_vec.y) || (0.0 <= grad_vec.x && grad_vec.y < 0.0))
+        coords.x -= grad_width;
+
+    float frac = dot(coords, grad_vec) / dot(grad_vec, grad_vec);
+
+    if (grad_vec.y < 0.0)
+        frac += 1.0;
+
+    frac = clamp(frac, 0.0, 1.0);
+    vec4 out_color = mix(color_from, color_to, frac);
+
+#if defined(DEBUG_FLAGS)
+    if (tint == 1.0)
+        out_color = vec4(0.0, 0.3, 0.0, 0.2) + out_color * 0.8;
+#endif
+
+    gl_FragColor = out_color;
+}

src/render_helpers/shaders/mod.rs

@@ -0,0 +1,68 @@
+use smithay::backend::renderer::gles::{GlesPixelProgram, GlesRenderer, UniformName, UniformType};
+
+use super::primary_gpu_pixel_shader_with_textures::PixelWithTexturesProgram;
+use super::renderer::NiriRenderer;
+
+pub struct Shaders {
+    pub gradient_border: Option<GlesPixelProgram>,
+    pub crossfade: Option<PixelWithTexturesProgram>,
+}
+
+impl Shaders {
+    fn compile(renderer: &mut GlesRenderer) -> Self {
+        let _span = tracy_client::span!("Shaders::compile");
+
+        let gradient_border = renderer
+            .compile_custom_pixel_shader(
+                include_str!("gradient_border.frag"),
+                &[
+                    UniformName::new("color_from", UniformType::_4f),
+                    UniformName::new("color_to", UniformType::_4f),
+                    UniformName::new("grad_offset", UniformType::_2f),
+                    UniformName::new("grad_width", UniformType::_1f),
+                    UniformName::new("grad_vec", UniformType::_2f),
+                ],
+            )
+            .map_err(|err| {
+                warn!("error compiling gradient border shader: {err:?}");
+            })
+            .ok();
+
+        let crossfade = PixelWithTexturesProgram::compile(
+            renderer,
+            include_str!("crossfade.frag"),
+            &[
+                UniformName::new("tex_from_loc", UniformType::_2f),
+                UniformName::new("tex_from_size", UniformType::_2f),
+                UniformName::new("tex_to_loc", UniformType::_2f),
+                UniformName::new("tex_to_size", UniformType::_2f),
+                UniformName::new("amount", UniformType::_1f),
+            ],
+            &["tex_from", "tex_to"],
+        )
+        .map_err(|err| {
+            warn!("error compiling crossfade shader: {err:?}");
+        })
+        .ok();
+
+        Self {
+            gradient_border,
+            crossfade,
+        }
+    }
+
+    pub fn get(renderer: &mut impl NiriRenderer) -> &Self {
+        let renderer = renderer.as_gles_renderer();
+        let data = renderer.egl_context().user_data();
+        data.get()
+            .expect("shaders::init() must be called when creating the renderer")
+    }
+}
+
+pub fn init(renderer: &mut GlesRenderer) {
+    let shaders = Shaders::compile(renderer);
+    let data = renderer.egl_context().user_data();
+    if !data.insert_if_missing(|| shaders) {
+        error!("shaders were already compiled");
+    }
+}

src/render_helpers/shaders/texture.vert

@@ -0,0 +1,25 @@
+#version 100
+
+uniform mat3 matrix;
+uniform mat3 tex_matrix;
+
+attribute vec2 vert;
+attribute vec4 vert_position;
+
+varying vec2 v_coords;
+
+mat2 scale(vec2 scale_vec){
+    return mat2(
+        scale_vec.x, 0.0,
+        0.0, scale_vec.y
+    );
+}
+
+void main() {
+    vec2 vert_transform_translation = vert_position.xy;
+    vec2 vert_transform_scale = vert_position.zw;
+    vec3 position = vec3(vert * scale(vert_transform_scale) + vert_transform_translation, 1.0);
+    v_coords = (tex_matrix * position).xy;
+    gl_Position = vec4(matrix * position, 1.0);
+}
+

src/render_helpers/snapshot.rs

@@ -0,0 +1,111 @@
+use std::cell::OnceCell;
+
+use niri_config::BlockOutFrom;
+use smithay::backend::allocator::Fourcc;
+use smithay::backend::renderer::element::{Kind, RenderElement};
+use smithay::backend::renderer::gles::{GlesRenderer, GlesTexture};
+use smithay::utils::{Logical, Physical, Point, Rectangle, Scale, Size, Transform};
+
+use super::{render_to_encompassing_texture, RenderTarget, ToRenderElement};
+
+/// Snapshot of a render.
+#[derive(Debug)]
+pub struct RenderSnapshot<C, B> {
+    /// Contents for a normal render.
+    ///
+    /// Relative to the geometry.
+    pub contents: Vec<C>,
+
+    /// Blocked-out contents.
+    ///
+    /// Relative to the geometry.
+    pub blocked_out_contents: Vec<B>,
+
+    /// Where the contents were blocked out from at the time of the snapshot.
+    pub block_out_from: Option<BlockOutFrom>,
+
+    /// Visual size of the element at the point of the snapshot.
+    pub size: Size<i32, Logical>,
+
+    /// Contents rendered into a texture (lazily).
+    pub texture: OnceCell<Option<(GlesTexture, Rectangle<i32, Physical>)>>,
+
+    /// Blocked-out contents rendered into a texture (lazily).
+    pub blocked_out_texture: OnceCell<Option<(GlesTexture, Rectangle<i32, Physical>)>>,
+}
+
+impl<C, B, EC, EB> RenderSnapshot<C, B>
+where
+    C: ToRenderElement<RenderElement = EC>,
+    B: ToRenderElement<RenderElement = EB>,
+    EC: RenderElement<GlesRenderer>,
+    EB: RenderElement<GlesRenderer>,
+{
+    pub fn texture(
+        &self,
+        renderer: &mut GlesRenderer,
+        scale: Scale<f64>,
+        target: RenderTarget,
+    ) -> Option<&(GlesTexture, Rectangle<i32, Physical>)> {
+        let block_out = match self.block_out_from {
+            None => false,
+            Some(BlockOutFrom::Screencast) => target == RenderTarget::Screencast,
+            Some(BlockOutFrom::ScreenCapture) => target != RenderTarget::Output,
+        };
+
+        if block_out {
+            self.blocked_out_texture.get_or_init(|| {
+                let _span = tracy_client::span!("RenderSnapshot::Texture");
+
+                let elements: Vec<_> = self
+                    .blocked_out_contents
+                    .iter()
+                    .map(|baked| {
+                        baked.to_render_element(Point::from((0, 0)), scale, 1., Kind::Unspecified)
+                    })
+                    .collect();
+
+                match render_to_encompassing_texture(
+                    renderer,
+                    scale,
+                    Transform::Normal,
+                    Fourcc::Abgr8888,
+                    &elements,
+                ) {
+                    Ok((texture, _sync_point, geo)) => Some((texture, geo)),
+                    Err(err) => {
+                        warn!("error rendering blocked-out contents to texture: {err:?}");
+                        None
+                    }
+                }
+            })
+        } else {
+            self.texture.get_or_init(|| {
+                let _span = tracy_client::span!("RenderSnapshot::Texture");
+
+                let elements: Vec<_> = self
+                    .contents
+                    .iter()
+                    .map(|baked| {
+                        baked.to_render_element(Point::from((0, 0)), scale, 1., Kind::Unspecified)
+                    })
+                    .collect();
+
+                match render_to_encompassing_texture(
+                    renderer,
+                    scale,
+                    Transform::Normal,
+                    Fourcc::Abgr8888,
+                    &elements,
+                ) {
+                    Ok((texture, _sync_point, geo)) => Some((texture, geo)),
+                    Err(err) => {
+                        warn!("error rendering contents to texture: {err:?}");
+                        None
+                    }
+                }
+            })
+        }
+        .as_ref()
+    }
+}

src/render_helpers/surface.rs

@@ -0,0 +1,82 @@
+use smithay::backend::renderer::element::texture::TextureBuffer;
+use smithay::backend::renderer::gles::{GlesRenderer, GlesTexture};
+use smithay::backend::renderer::utils::{import_surface, RendererSurfaceStateUserData};
+use smithay::backend::renderer::Renderer as _;
+use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
+use smithay::utils::{Logical, Point};
+use smithay::wayland::compositor::{with_surface_tree_downward, TraversalAction};
+
+use super::BakedBuffer;
+
+/// Renders elements from a surface tree as textures into `storage`.
+pub fn render_snapshot_from_surface_tree(
+    renderer: &mut GlesRenderer,
+    surface: &WlSurface,
+    location: Point<i32, Logical>,
+    storage: &mut Vec<BakedBuffer<TextureBuffer<GlesTexture>>>,
+) {
+    let _span = tracy_client::span!("render_snapshot_from_surface_tree");
+
+    with_surface_tree_downward(
+        surface,
+        location,
+        |_, states, location| {
+            let mut location = *location;
+            let data = states.data_map.get::<RendererSurfaceStateUserData>();
+
+            if let Some(data) = data {
+                let data = &*data.borrow();
+
+                if let Some(view) = data.view() {
+                    location += view.offset;
+                    TraversalAction::DoChildren(location)
+                } else {
+                    TraversalAction::SkipChildren
+                }
+            } else {
+                TraversalAction::SkipChildren
+            }
+        },
+        |_, states, location| {
+            let mut location = *location;
+            let data = states.data_map.get::<RendererSurfaceStateUserData>();
+
+            if let Some(data) = data {
+                if let Some(view) = data.borrow().view() {
+                    location += view.offset;
+                } else {
+                    return;
+                }
+
+                if let Err(err) = import_surface(renderer, states) {
+                    warn!("failed to import surface: {err:?}");
+                    return;
+                }
+
+                let data = data.borrow();
+                let view = data.view().unwrap();
+                let Some(texture) = data.texture::<GlesRenderer>(renderer.id()) else {
+                    return;
+                };
+
+                let buffer = TextureBuffer::from_texture(
+                    renderer,
+                    texture.clone(),
+                    data.buffer_scale(),
+                    data.buffer_transform(),
+                    None,
+                );
+
+                let baked = BakedBuffer {
+                    buffer,
+                    location,
+                    src: Some(view.src),
+                    dst: Some(view.dst),
+                };
+
+                storage.push(baked);
+            }
+        },
+        |_, _, _| true,
+    );
+}

src/rubber_band.rs

@@ -0,0 +1,39 @@
+#[derive(Debug, Clone, Copy)]
+pub struct RubberBand {
+    pub stiffness: f64,
+    pub limit: f64,
+}
+
+impl RubberBand {
+    pub fn band(&self, x: f64) -> f64 {
+        let c = self.stiffness;
+        let d = self.limit;
+
+        (1. - (1. / (x * c / d + 1.))) * d
+    }
+
+    pub fn derivative(&self, x: f64) -> f64 {
+        let c = self.stiffness;
+        let d = self.limit;
+
+        c * d * d / (c * x + d).powi(2)
+    }
+
+    pub fn clamp(&self, min: f64, max: f64, x: f64) -> f64 {
+        let clamped = x.clamp(min, max);
+        let sign = if x < clamped { -1. } else { 1. };
+        let diff = (x - clamped).abs();
+
+        clamped + sign * self.band(diff)
+    }
+
+    pub fn clamp_derivative(&self, min: f64, max: f64, x: f64) -> f64 {
+        if min <= x && x <= max {
+            return 1.;
+        }
+
+        let clamped = x.clamp(min, max);
+        let diff = (x - clamped).abs();
+        self.derivative(diff)
+    }
+}

src/scroll_tracker.rs

@@ -0,0 +1,40 @@
+pub struct ScrollTracker {
+    tick: f64,
+    last: f64,
+    acc: f64,
+}
+
+impl ScrollTracker {
+    #[allow(clippy::new_without_default)]
+    pub fn new(tick: i8) -> Self {
+        Self {
+            tick: f64::from(tick),
+            last: 0.,
+            acc: 0.,
+        }
+    }
+
+    pub fn accumulate(&mut self, amount: f64) -> i8 {
+        let changed_direction = (self.last > 0. && amount < 0.) || (self.last < 0. && amount > 0.);
+        if changed_direction {
+            self.acc = 0.
+        }
+
+        self.last = amount;
+        self.acc += amount;
+
+        let mut ticks = 0;
+        if self.acc.abs() >= self.tick {
+            let clamped = self.acc.clamp(-127. * self.tick, 127. * self.tick);
+            ticks = (clamped as i16 / self.tick as i16) as i8;
+            self.acc %= self.tick;
+        }
+
+        ticks
+    }
+
+    pub fn reset(&mut self) {
+        self.last = 0.;
+        self.acc = 0.;
+    }
+}

src/swipe_tracker.rs

@@ -0,0 +1,87 @@
+use std::collections::VecDeque;
+use std::time::Duration;
+
+const HISTORY_LIMIT: Duration = Duration::from_millis(150);
+const DECELERATION_TOUCHPAD: f64 = 0.997;
+
+#[derive(Debug)]
+pub struct SwipeTracker {
+    history: VecDeque<Event>,
+    pos: f64,
+}
+
+#[derive(Debug, Clone, Copy)]
+struct Event {
+    delta: f64,
+    timestamp: Duration,
+}
+
+impl SwipeTracker {
+    #[allow(clippy::new_without_default)]
+    pub fn new() -> Self {
+        Self {
+            history: VecDeque::new(),
+            pos: 0.,
+        }
+    }
+
+    /// Pushes a new reading into the tracker.
+    pub fn push(&mut self, delta: f64, timestamp: Duration) {
+        // For the events that we care about, timestamps should always increase
+        // monotonically.
+        if let Some(last) = self.history.back() {
+            if timestamp < last.timestamp {
+                trace!(
+                    "ignoring event with timestamp {timestamp:?} earlier than last {:?}",
+                    last.timestamp
+                );
+                return;
+            }
+        }
+
+        self.history.push_back(Event { delta, timestamp });
+        self.pos += delta;
+
+        self.trim_history();
+    }
+
+    /// Returns the current gesture position.
+    pub fn pos(&self) -> f64 {
+        self.pos
+    }
+
+    /// Computes the current gesture velocity.
+    pub fn velocity(&self) -> f64 {
+        let (Some(first), Some(last)) = (self.history.front(), self.history.back()) else {
+            return 0.;
+        };
+
+        let total_time = (last.timestamp - first.timestamp).as_secs_f64();
+        if total_time == 0. {
+            return 0.;
+        }
+
+        let total_delta = self.history.iter().map(|event| event.delta).sum::<f64>();
+        total_delta / total_time
+    }
+
+    /// Computes the gesture end position after decelerating to a halt.
+    pub fn projected_end_pos(&self) -> f64 {
+        let vel = self.velocity();
+        self.pos - vel / (1000. * DECELERATION_TOUCHPAD.ln())
+    }
+
+    fn trim_history(&mut self) {
+        let Some(&Event { timestamp, .. }) = self.history.back() else {
+            return;
+        };
+
+        while let Some(first) = self.history.front() {
+            if timestamp <= first.timestamp + HISTORY_LIMIT {
+                break;
+            }
+
+            let _ = self.history.pop_front();
+        }
+    }
+}

src/ui/config_error_notification.rs

@@ -1,7 +1,10 @@
 use std::cell::RefCell;
 use std::collections::HashMap;
+use std::path::{Path, PathBuf};
+use std::rc::Rc;
 use std::time::Duration;
 
+use niri_config::Config;
 use pangocairo::cairo::{self, ImageSurface};
 use pangocairo::pango::FontDescription;
 use smithay::backend::renderer::element::memory::{
@@ -14,7 +17,7 @@ use smithay::reexports::gbm::Format as Fourcc;
 use smithay::utils::Transform;
 
 use crate::animation::Animation;
-use crate::render_helpers::NiriRenderer;
+use crate::render_helpers::renderer::NiriRenderer;
 
 const TEXT: &str = "Failed to parse the config file. \
                     Please run <span face='monospace' bgcolor='#000000'>niri validate</span> \
@@ -26,6 +29,12 @@ const BORDER: i32 = 4;
 pub struct ConfigErrorNotification {
     state: State,
     buffers: RefCell<HashMap<i32, Option<MemoryRenderBuffer>>>,
+
+    // If set, this is a "Created config at {path}" notification. If unset, this is a config error
+    // notification.
+    created_path: Option<PathBuf>,
+
+    config: Rc<RefCell<Config>>,
 }
 
 enum State {
@@ -39,16 +48,37 @@ pub type ConfigErrorNotificationRenderElement<R> =
     RelocateRenderElement<MemoryRenderBufferRenderElement<R>>;
 
 impl ConfigErrorNotification {
-    pub fn new() -> Self {
+    pub fn new(config: Rc<RefCell<Config>>) -> Self {
         Self {
             state: State::Hidden,
             buffers: RefCell::new(HashMap::new()),
+            created_path: None,
+            config,
         }
     }
 
+    fn animation(&self, from: f64, to: f64) -> Animation {
+        let c = self.config.borrow();
+        Animation::new(from, to, 0., c.animations.config_notification_open_close.0)
+    }
+
+    pub fn show_created(&mut self, created_path: Option<PathBuf>) {
+        if self.created_path != created_path {
+            self.created_path = created_path;
+            self.buffers.borrow_mut().clear();
+        }
+
+        self.state = State::Showing(self.animation(0., 1.));
+    }
+
     pub fn show(&mut self) {
+        if self.created_path.is_some() {
+            self.created_path = None;
+            self.buffers.borrow_mut().clear();
+        }
+
         // Show from scratch even if already showing to bring attention.
-        self.state = State::Showing(Animation::new(0., 1., Duration::from_millis(250)));
+        self.state = State::Showing(self.animation(0., 1.));
     }
 
     pub fn hide(&mut self) {
@@ -56,7 +86,7 @@ impl ConfigErrorNotification {
             return;
         }
 
-        self.state = State::Hiding(Animation::new(1., 0., Duration::from_millis(250)));
+        self.state = State::Hiding(self.animation(1., 0.));
     }
 
     pub fn advance_animations(&mut self, target_presentation_time: Duration) {
@@ -65,7 +95,15 @@ impl ConfigErrorNotification {
             State::Showing(anim) => {
                 anim.set_current_time(target_presentation_time);
                 if anim.is_done() {
-                    self.state = State::Shown(target_presentation_time + Duration::from_secs(4));
+                    let duration = if self.created_path.is_some() {
+                        // Make this quite a bit longer because it comes with a monitor modeset
+                        // (can take a while) and an important hotkeys popup diverting the
+                        // attention.
+                        Duration::from_secs(8)
+                    } else {
+                        Duration::from_secs(4)
+                    };
+                    self.state = State::Shown(target_presentation_time + duration);
                 }
             }
             State::Shown(deadline) => {
@@ -75,7 +113,7 @@ impl ConfigErrorNotification {
             }
             State::Hiding(anim) => {
                 anim.set_current_time(target_presentation_time);
-                if anim.is_done() {
+                if anim.is_clamped_done() {
                     self.state = State::Hidden;
                 }
             }
@@ -96,11 +134,12 @@ impl ConfigErrorNotification {
         }
 
         let scale = output.current_scale().integer_scale();
+        let path = self.created_path.as_deref();
 
         let mut buffers = self.buffers.borrow_mut();
         let buffer = buffers
             .entry(scale)
-            .or_insert_with_key(move |&scale| render(scale).ok());
+            .or_insert_with_key(move |&scale| render(scale, path).ok());
         let buffer = buffer.as_ref()?;
 
         let elem = MemoryRenderBufferRenderElement::from_buffer(
@@ -138,19 +177,30 @@ impl ConfigErrorNotification {
     }
 }
 
-fn render(scale: i32) -> anyhow::Result<MemoryRenderBuffer> {
+fn render(scale: i32, created_path: Option<&Path>) -> anyhow::Result<MemoryRenderBuffer> {
     let _span = tracy_client::span!("config_error_notification::render");
 
     let padding = PADDING * scale;
 
+    let mut text = String::from(TEXT);
+    let mut border_color = (1., 0.3, 0.3);
+    if let Some(path) = created_path {
+        text = format!(
+            "Created a default config file at \
+             <span face='monospace' bgcolor='#000000'>{:?}</span>",
+            path
+        );
+        border_color = (0.5, 1., 0.5);
+    };
+
     let mut font = FontDescription::from_string(FONT);
     font.set_absolute_size((font.size() * scale).into());
 
     let surface = ImageSurface::create(cairo::Format::ARgb32, 0, 0)?;
     let cr = cairo::Context::new(&surface)?;
-    let layout = pangocairo::create_layout(&cr);
+    let layout = pangocairo::functions::create_layout(&cr);
     layout.set_font_description(Some(&font));
-    layout.set_markup(TEXT);
+    layout.set_markup(&text);
 
     let (mut width, mut height) = layout.pixel_size();
     width += padding * 2;
@@ -166,25 +216,25 @@ fn render(scale: i32) -> anyhow::Result<MemoryRenderBuffer> {
     cr.paint()?;
 
     cr.move_to(padding.into(), padding.into());
-    let layout = pangocairo::create_layout(&cr);
+    let layout = pangocairo::functions::create_layout(&cr);
     layout.set_font_description(Some(&font));
-    layout.set_markup(TEXT);
+    layout.set_markup(&text);
 
     cr.set_source_rgb(1., 1., 1.);
-    pangocairo::show_layout(&cr, &layout);
+    pangocairo::functions::show_layout(&cr, &layout);
 
     cr.move_to(0., 0.);
     cr.line_to(width.into(), 0.);
     cr.line_to(width.into(), height.into());
     cr.line_to(0., height.into());
     cr.line_to(0., 0.);
-    cr.set_source_rgb(1., 0.3, 0.3);
+    cr.set_source_rgb(border_color.0, border_color.1, border_color.2);
     cr.set_line_width((BORDER * scale).into());
     cr.stroke()?;
     drop(cr);
 
     let data = surface.take_data().unwrap();
-    let buffer = MemoryRenderBuffer::from_memory(
+    let buffer = MemoryRenderBuffer::from_slice(
         &data,
         Fourcc::Argb8888,
         (width, height),

src/ui/exit_confirm_dialog.rs

@@ -12,7 +12,7 @@ use smithay::output::Output;
 use smithay::reexports::gbm::Format as Fourcc;
 use smithay::utils::Transform;
 
-use crate::render_helpers::NiriRenderer;
+use crate::render_helpers::renderer::NiriRenderer;
 
 const TEXT: &str = "Are you sure you want to exit niri?\n\n\
                     Press <span face='mono' bgcolor='#2C2C2C'> Enter </span> to confirm.";
@@ -111,7 +111,7 @@ fn render(scale: i32) -> anyhow::Result<MemoryRenderBuffer> {
 
     let surface = ImageSurface::create(cairo::Format::ARgb32, 0, 0)?;
     let cr = cairo::Context::new(&surface)?;
-    let layout = pangocairo::create_layout(&cr);
+    let layout = pangocairo::functions::create_layout(&cr);
     layout.set_font_description(Some(&font));
     layout.set_alignment(Alignment::Center);
     layout.set_markup(TEXT);
@@ -130,13 +130,13 @@ fn render(scale: i32) -> anyhow::Result<MemoryRenderBuffer> {
     cr.paint()?;
 
     cr.move_to(padding.into(), padding.into());
-    let layout = pangocairo::create_layout(&cr);
+    let layout = pangocairo::functions::create_layout(&cr);
     layout.set_font_description(Some(&font));
     layout.set_alignment(Alignment::Center);
     layout.set_markup(TEXT);
 
     cr.set_source_rgb(1., 1., 1.);
-    pangocairo::show_layout(&cr, &layout);
+    pangocairo::functions::show_layout(&cr, &layout);
 
     cr.move_to(0., 0.);
     cr.line_to(width.into(), 0.);
@@ -149,7 +149,7 @@ fn render(scale: i32) -> anyhow::Result<MemoryRenderBuffer> {
     drop(cr);
 
     let data = surface.take_data().unwrap();
-    let buffer = MemoryRenderBuffer::from_memory(
+    let buffer = MemoryRenderBuffer::from_slice(
         &data,
         Fourcc::Argb8888,
         (width, height),

src/ui/hotkey_overlay.rs

@@ -4,7 +4,7 @@ use std::collections::HashMap;
 use std::iter::zip;
 use std::rc::Rc;
 
-use niri_config::{Action, Config, Key, Modifiers};
+use niri_config::{Action, Config, Key, Modifiers, Trigger};
 use pangocairo::cairo::{self, ImageSurface};
 use pangocairo::pango::{AttrColor, AttrInt, AttrList, AttrString, FontDescription, Weight};
 use smithay::backend::renderer::element::memory::{
@@ -18,7 +18,7 @@ use smithay::reexports::gbm::Format as Fourcc;
 use smithay::utils::{Physical, Size, Transform};
 
 use crate::input::CompositorMod;
-use crate::render_helpers::NiriRenderer;
+use crate::render_helpers::renderer::NiriRenderer;
 
 const PADDING: i32 = 8;
 const MARGIN: i32 = PADDING * 2;
@@ -155,13 +155,20 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
     let binds = &config.binds.0;
 
     // Collect actions that we want to show.
-    let mut actions = vec![
+    let mut actions = vec![&Action::ShowHotkeyOverlay];
-        &Action::ShowHotkeyOverlay,
+
-        &Action::Quit,
+    // Prefer Quit(false) if found, otherwise try Quit(true), and if there's neither, fall back to
-        &Action::CloseWindow,
+    // Quit(false).
-    ];
+    if binds.iter().any(|bind| bind.action == Action::Quit(false)) {
+        actions.push(&Action::Quit(false));
+    } else if binds.iter().any(|bind| bind.action == Action::Quit(true)) {
+        actions.push(&Action::Quit(true));
+    } else {
+        actions.push(&Action::Quit(false));
+    }
 
     actions.extend(&[
+        &Action::CloseWindow,
         &Action::FocusColumnLeft,
         &Action::FocusColumnRight,
         &Action::MoveColumnLeft,
@@ -173,12 +180,12 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
     // Prefer move-column-to-workspace-down, but fall back to move-window-to-workspace-down.
     if binds
         .iter()
-        .any(|bind| bind.actions.first() == Some(&Action::MoveColumnToWorkspaceDown))
+        .any(|bind| bind.action == Action::MoveColumnToWorkspaceDown)
     {
         actions.push(&Action::MoveColumnToWorkspaceDown);
     } else if binds
         .iter()
-        .any(|bind| bind.actions.first() == Some(&Action::MoveWindowToWorkspaceDown))
+        .any(|bind| bind.action == Action::MoveWindowToWorkspaceDown)
     {
         actions.push(&Action::MoveWindowToWorkspaceDown);
     } else {
@@ -188,12 +195,12 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
     // Same for -up.
     if binds
         .iter()
-        .any(|bind| bind.actions.first() == Some(&Action::MoveColumnToWorkspaceUp))
+        .any(|bind| bind.action == Action::MoveColumnToWorkspaceUp)
     {
         actions.push(&Action::MoveColumnToWorkspaceUp);
     } else if binds
         .iter()
-        .any(|bind| bind.actions.first() == Some(&Action::MoveWindowToWorkspaceUp))
+        .any(|bind| bind.action == Action::MoveWindowToWorkspaceUp)
     {
         actions.push(&Action::MoveWindowToWorkspaceUp);
     } else {
@@ -208,20 +215,28 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
     ]);
 
     // Screenshot is not as important, can omit if not bound.
-    if binds
+    if binds.iter().any(|bind| bind.action == Action::Screenshot) {
-        .iter()
-        .any(|bind| bind.actions.first() == Some(&Action::Screenshot))
-    {
         actions.push(&Action::Screenshot);
     }
 
     // Add the spawn actions.
-    for bind in binds
+    let mut spawn_actions = Vec::new();
-        .iter()
+    for bind in binds.iter().filter(|bind| {
-        .filter(|bind| matches!(bind.actions.first(), Some(Action::Spawn(_))))
+        matches!(bind.action, Action::Spawn(_))
-    {
+            // Only show binds with Mod or Super to filter out stuff like volume up/down.
-        actions.push(bind.actions.first().unwrap());
+            && (bind.key.modifiers.contains(Modifiers::COMPOSITOR)
+                || bind.key.modifiers.contains(Modifiers::SUPER))
+            // Also filter out wheel and touchpad scroll binds.
+            && matches!(bind.key.trigger, Trigger::Keysym(_))
+    }) {
+        let action = &bind.action;
+
+        // We only show one bind for each action, so we need to deduplicate the Spawn actions.
+        if !spawn_actions.contains(&action) {
+            spawn_actions.push(action);
+        }
     }
+    actions.extend(spawn_actions);
 
     let strings = actions
         .into_iter()
@@ -230,7 +245,7 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
                 .binds
                 .0
                 .iter()
-                .find(|bind| bind.actions.first() == Some(action))
+                .find(|bind| bind.action == *action)
                 .map(|bind| key_name(comp_mod, &bind.key))
                 .unwrap_or_else(|| String::from("(not bound)"));
 
@@ -243,7 +258,7 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
 
     let surface = ImageSurface::create(cairo::Format::ARgb32, 0, 0)?;
     let cr = cairo::Context::new(&surface)?;
-    let layout = pangocairo::create_layout(&cr);
+    let layout = pangocairo::functions::create_layout(&cr);
     layout.set_font_description(Some(&font));
 
     let bold = AttrList::new();
@@ -298,7 +313,7 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
     cr.paint()?;
 
     cr.move_to(padding.into(), padding.into());
-    let layout = pangocairo::create_layout(&cr);
+    let layout = pangocairo::functions::create_layout(&cr);
     layout.set_font_description(Some(&font));
 
     cr.set_source_rgb(1., 1., 1.);
@@ -306,20 +321,20 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
     cr.move_to(((width - title_size.0) / 2).into(), padding.into());
     layout.set_attributes(Some(&bold));
     layout.set_text(TITLE);
-    pangocairo::show_layout(&cr, &layout);
+    pangocairo::functions::show_layout(&cr, &layout);
 
     cr.move_to(padding.into(), (padding + title_size.1 + padding).into());
 
     for ((key, action), ((_, key_h), (_, act_h))) in zip(&strings, zip(&key_sizes, &action_sizes)) {
         layout.set_attributes(Some(&attrs));
         layout.set_text(key);
-        pangocairo::show_layout(&cr, &layout);
+        pangocairo::functions::show_layout(&cr, &layout);
 
         cr.rel_move_to((key_width + padding).into(), 0.);
 
         layout.set_attributes(None);
         layout.set_markup(action);
-        pangocairo::show_layout(&cr, &layout);
+        pangocairo::functions::show_layout(&cr, &layout);
 
         cr.rel_move_to(
             (-(key_width + padding)).into(),
@@ -338,7 +353,7 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
     drop(cr);
 
     let data = surface.take_data().unwrap();
-    let buffer = MemoryRenderBuffer::from_memory(
+    let buffer = MemoryRenderBuffer::from_slice(
         &data,
         Fourcc::Argb8888,
         (width, height),
@@ -356,7 +371,7 @@ fn render(config: &Config, comp_mod: CompositorMod, scale: i32) -> anyhow::Resul
 
 fn action_name(action: &Action) -> String {
     match action {
-        Action::Quit => String::from("Exit niri"),
+        Action::Quit(_) => String::from("Exit niri"),
         Action::ShowHotkeyOverlay => String::from("Show Important Hotkeys"),
         Action::CloseWindow => String::from("Close Focused Window"),
         Action::FocusColumnLeft => String::from("Focus Column to the Left"),
@@ -401,7 +416,19 @@ fn key_name(comp_mod: CompositorMod, key: &Key) -> String {
     if key.modifiers.contains(Modifiers::CTRL) {
         name.push_str("Ctrl + ");
     }
-    name.push_str(&prettify_keysym_name(&keysym_get_name(key.keysym)));
+
+    let pretty = match key.trigger {
+        Trigger::Keysym(keysym) => prettify_keysym_name(&keysym_get_name(keysym)),
+        Trigger::WheelScrollDown => String::from("Wheel Scroll Down"),
+        Trigger::WheelScrollUp => String::from("Wheel Scroll Up"),
+        Trigger::WheelScrollLeft => String::from("Wheel Scroll Left"),
+        Trigger::WheelScrollRight => String::from("Wheel Scroll Right"),
+        Trigger::TouchpadScrollDown => String::from("Touchpad Scroll Down"),
+        Trigger::TouchpadScrollUp => String::from("Touchpad Scroll Up"),
+        Trigger::TouchpadScrollLeft => String::from("Touchpad Scroll Left"),
+        Trigger::TouchpadScrollRight => String::from("Touchpad Scroll Right"),
+    };
+    name.push_str(&pretty);
 
     name
 }

src/ui/mod.rs

@@ -0,0 +1,4 @@
+pub mod config_error_notification;
+pub mod exit_confirm_dialog;
+pub mod hotkey_overlay;
+pub mod screenshot_ui;

src/ui/screenshot_ui.rs

@@ -10,16 +10,16 @@ use smithay::backend::allocator::Fourcc;
 use smithay::backend::input::{ButtonState, MouseButton};
 use smithay::backend::renderer::element::solid::{SolidColorBuffer, SolidColorRenderElement};
 use smithay::backend::renderer::element::texture::{TextureBuffer, TextureRenderElement};
-use smithay::backend::renderer::element::{Element, Id, Kind, RenderElement, UnderlyingStorage};
+use smithay::backend::renderer::element::Kind;
-use smithay::backend::renderer::gles::{GlesError, GlesFrame, GlesRenderer, GlesTexture};
+use smithay::backend::renderer::gles::{GlesRenderer, GlesTexture};
-use smithay::backend::renderer::utils::CommitCounter;
 use smithay::backend::renderer::ExportMem;
 use smithay::input::keyboard::{Keysym, ModifiersState};
 use smithay::output::{Output, WeakOutput};
-use smithay::utils::{Buffer, Physical, Point, Rectangle, Scale, Size, Transform};
+use smithay::utils::{Physical, Point, Rectangle, Size, Transform};
 
-use crate::backend::tty::{TtyFrame, TtyRenderer, TtyRendererError};
+use crate::niri_render_elements;
-use crate::render_helpers::PrimaryGpuTextureRenderElement;
+use crate::render_helpers::primary_gpu_texture::PrimaryGpuTextureRenderElement;
+use crate::render_helpers::RenderTarget;
 
 const BORDER: i32 = 2;
 
@@ -42,16 +42,19 @@ pub enum ScreenshotUi {
 pub struct OutputData {
     size: Size<i32, Physical>,
     scale: i32,
-    texture: GlesTexture,
+    transform: Transform,
-    texture_buffer: TextureBuffer<GlesTexture>,
+    // Output, screencast, screen capture.
+    texture: [GlesTexture; 3],
+    texture_buffer: [TextureBuffer<GlesTexture>; 3],
     buffers: [SolidColorBuffer; 8],
     locations: [Point<i32, Physical>; 8],
 }
 
-#[derive(Debug)]
+niri_render_elements! {
-pub enum ScreenshotUiRenderElement {
+    ScreenshotUiRenderElement => {
-    Screenshot(PrimaryGpuTextureRenderElement),
+        Screenshot = PrimaryGpuTextureRenderElement,
-    SolidColor(SolidColorRenderElement),
+        SolidColor = SolidColorRenderElement,
+    }
 }
 
 impl ScreenshotUi {
@@ -64,7 +67,8 @@ impl ScreenshotUi {
     pub fn open(
         &mut self,
         renderer: &GlesRenderer,
-        screenshots: HashMap<Output, GlesTexture>,
+        // Output, screencast, screen capture.
+        screenshots: HashMap<Output, [GlesTexture; 3]>,
         default_output: Output,
     ) -> bool {
         if screenshots.is_empty() {
@@ -94,6 +98,7 @@ impl ScreenshotUi {
                 )
             }
         };
+
         let scale = selection.0.current_scale().integer_scale();
         let selection = (
             selection.0,
@@ -104,17 +109,13 @@ impl ScreenshotUi {
         let output_data = screenshots
             .into_iter()
             .map(|(output, texture)| {
-                let output_transform = output.current_transform();
+                let transform = output.current_transform();
                 let output_mode = output.current_mode().unwrap();
-                let size = output_transform.transform_size(output_mode.size);
+                let size = transform.transform_size(output_mode.size);
                 let scale = output.current_scale().integer_scale();
-                let texture_buffer = TextureBuffer::from_texture(
+                let texture_buffer = texture.clone().map(|texture| {
-                    renderer,
+                    TextureBuffer::from_texture(renderer, texture, scale, Transform::Normal, None)
-                    texture.clone(),
+                });
-                    scale,
-                    Transform::Normal,
-                    None,
-                );
                 let buffers = [
                     SolidColorBuffer::new((0, 0), [1., 1., 1., 1.]),
                     SolidColorBuffer::new((0, 0), [1., 1., 1., 1.]),
@@ -129,6 +130,7 @@ impl ScreenshotUi {
                 let data = OutputData {
                     size,
                     scale,
+                    transform,
                     texture,
                     texture_buffer,
                     buffers,
@@ -240,7 +242,11 @@ impl ScreenshotUi {
         }
     }
 
-    pub fn render_output(&self, output: &Output) -> ArrayVec<ScreenshotUiRenderElement, 9> {
+    pub fn render_output(
+        &self,
+        output: &Output,
+        target: RenderTarget,
+    ) -> ArrayVec<ScreenshotUiRenderElement, 9> {
         let _span = tracy_client::span!("ScreenshotUi::render_output");
 
         let Self::Open { output_data, .. } = self else {
@@ -266,10 +272,15 @@ impl ScreenshotUi {
         }));
 
         // The screenshot itself goes last.
+        let index = match target {
+            RenderTarget::Output => 0,
+            RenderTarget::Screencast => 1,
+            RenderTarget::ScreenCapture => 2,
+        };
         elements.push(
             PrimaryGpuTextureRenderElement(TextureRenderElement::from_texture_buffer(
                 (0., 0.),
-                &output_data.texture_buffer,
+                &output_data.texture_buffer[index],
                 None,
                 None,
                 None,
@@ -304,7 +315,7 @@ impl ScreenshotUi {
             .to_buffer(1, Transform::Normal, &data.size.to_logical(1));
 
         let mapping = renderer
-            .copy_texture(&data.texture, buf_rect, Fourcc::Abgr8888)
+            .copy_texture(&data.texture[0], buf_rect, Fourcc::Abgr8888)
             .context("error copying texture")?;
         let copy = renderer
             .map_texture(&mapping)
@@ -313,12 +324,12 @@ impl ScreenshotUi {
         Ok((rect.size, copy.to_vec()))
     }
 
-    pub fn action(&self, raw: Option<Keysym>, mods: ModifiersState) -> Option<Action> {
+    pub fn action(&self, raw: Keysym, mods: ModifiersState) -> Option<Action> {
         if !matches!(self, Self::Open { .. }) {
             return None;
         }
 
-        action(raw?, mods)
+        action(raw, mods)
     }
 
     pub fn selection_output(&self) -> Option<&Output> {
@@ -333,10 +344,10 @@ impl ScreenshotUi {
         }
     }
 
-    pub fn output_size(&self, output: &Output) -> Option<(Size<i32, Physical>, i32)> {
+    pub fn output_size(&self, output: &Output) -> Option<(Size<i32, Physical>, i32, Transform)> {
         if let Self::Open { output_data, .. } = self {
             let data = output_data.get(output)?;
-            Some((data.size, data.scale))
+            Some((data.size, data.scale, data.transform))
         } else {
             None
         }
@@ -448,138 +459,3 @@ pub fn rect_from_corner_points(
     let y2 = max(a.y, b.y);
     Rectangle::from_extemities((x1, y1), (x2 + scale, y2 + scale))
 }
-
-// Manual RenderElement implementation due to AsGlesFrame requirement.
-impl Element for ScreenshotUiRenderElement {
-    fn id(&self) -> &Id {
-        match self {
-            Self::Screenshot(elem) => elem.id(),
-            Self::SolidColor(elem) => elem.id(),
-        }
-    }
-
-    fn current_commit(&self) -> CommitCounter {
-        match self {
-            Self::Screenshot(elem) => elem.current_commit(),
-            Self::SolidColor(elem) => elem.current_commit(),
-        }
-    }
-
-    fn geometry(&self, scale: Scale<f64>) -> Rectangle<i32, Physical> {
-        match self {
-            Self::Screenshot(elem) => elem.geometry(scale),
-            Self::SolidColor(elem) => elem.geometry(scale),
-        }
-    }
-
-    fn transform(&self) -> Transform {
-        match self {
-            Self::Screenshot(elem) => elem.transform(),
-            Self::SolidColor(elem) => elem.transform(),
-        }
-    }
-
-    fn src(&self) -> Rectangle<f64, Buffer> {
-        match self {
-            Self::Screenshot(elem) => elem.src(),
-            Self::SolidColor(elem) => elem.src(),
-        }
-    }
-
-    fn damage_since(
-        &self,
-        scale: Scale<f64>,
-        commit: Option<CommitCounter>,
-    ) -> Vec<Rectangle<i32, Physical>> {
-        match self {
-            Self::Screenshot(elem) => elem.damage_since(scale, commit),
-            Self::SolidColor(elem) => elem.damage_since(scale, commit),
-        }
-    }
-
-    fn opaque_regions(&self, scale: Scale<f64>) -> Vec<Rectangle<i32, Physical>> {
-        match self {
-            Self::Screenshot(elem) => elem.opaque_regions(scale),
-            Self::SolidColor(elem) => elem.opaque_regions(scale),
-        }
-    }
-
-    fn alpha(&self) -> f32 {
-        match self {
-            Self::Screenshot(elem) => elem.alpha(),
-            Self::SolidColor(elem) => elem.alpha(),
-        }
-    }
-
-    fn kind(&self) -> Kind {
-        match self {
-            Self::Screenshot(elem) => elem.kind(),
-            Self::SolidColor(elem) => elem.kind(),
-        }
-    }
-}
-
-impl RenderElement<GlesRenderer> for ScreenshotUiRenderElement {
-    fn draw(
-        &self,
-        frame: &mut GlesFrame<'_>,
-        src: Rectangle<f64, Buffer>,
-        dst: Rectangle<i32, Physical>,
-        damage: &[Rectangle<i32, Physical>],
-    ) -> Result<(), GlesError> {
-        match self {
-            Self::Screenshot(elem) => {
-                RenderElement::<GlesRenderer>::draw(&elem, frame, src, dst, damage)
-            }
-            Self::SolidColor(elem) => {
-                RenderElement::<GlesRenderer>::draw(&elem, frame, src, dst, damage)
-            }
-        }
-    }
-
-    fn underlying_storage(&self, _renderer: &mut GlesRenderer) -> Option<UnderlyingStorage> {
-        // If scanout for things other than Wayland buffers is implemented, this will need to take
-        // the target GPU into account.
-        None
-    }
-}
-
-impl<'render, 'alloc> RenderElement<TtyRenderer<'render, 'alloc>> for ScreenshotUiRenderElement {
-    fn draw(
-        &self,
-        frame: &mut TtyFrame<'render, 'alloc, '_>,
-        src: Rectangle<f64, Buffer>,
-        dst: Rectangle<i32, Physical>,
-        damage: &[Rectangle<i32, Physical>],
-    ) -> Result<(), TtyRendererError<'render, 'alloc>> {
-        match self {
-            Self::Screenshot(elem) => {
-                RenderElement::<TtyRenderer<'render, 'alloc>>::draw(&elem, frame, src, dst, damage)
-            }
-            Self::SolidColor(elem) => {
-                RenderElement::<TtyRenderer<'render, 'alloc>>::draw(&elem, frame, src, dst, damage)
-            }
-        }
-    }
-
-    fn underlying_storage(
-        &self,
-        _renderer: &mut TtyRenderer<'render, 'alloc>,
-    ) -> Option<UnderlyingStorage> {
-        // If scanout for things other than Wayland buffers is implemented, this will need to take
-        // the target GPU into account.
-        None
-    }
-}
-
-impl From<SolidColorRenderElement> for ScreenshotUiRenderElement {
-    fn from(x: SolidColorRenderElement) -> Self {
-        Self::SolidColor(x)
-    }
-}
-
-impl From<PrimaryGpuTextureRenderElement> for ScreenshotUiRenderElement {
-    fn from(x: PrimaryGpuTextureRenderElement) -> Self {
-        Self::Screenshot(x)
-    }
-}

src/utils/id.rs

@@ -0,0 +1,27 @@
+use std::sync::atomic::{AtomicU32, Ordering};
+
+/// Counter that returns unique IDs.
+///
+/// Under the hood it uses a `u32` that will eventually wrap around. When incrementing it once a
+/// second, it will wrap around after about 136 years.
+pub struct IdCounter {
+    value: AtomicU32,
+}
+
+impl IdCounter {
+    pub const fn new() -> Self {
+        Self {
+            value: AtomicU32::new(0),
+        }
+    }
+
+    pub fn next(&self) -> u32 {
+        self.value.fetch_add(1, Ordering::SeqCst)
+    }
+}
+
+impl Default for IdCounter {
+    fn default() -> Self {
+        Self::new()
+    }
+}

src/utils/mod.rs

@@ -1,23 +1,31 @@
 use std::ffi::{CString, OsStr};
-use std::io::{self, Write};
+use std::io::Write;
 use std::os::unix::prelude::OsStrExt;
-use std::os::unix::process::CommandExt;
+use std::path::{Path, PathBuf};
-use std::path::PathBuf;
-use std::process::{Command, Stdio};
 use std::ptr::null_mut;
-use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::atomic::AtomicBool;
-use std::thread;
 use std::time::Duration;
 
 use anyhow::{ensure, Context};
 use directories::UserDirs;
+use git_version::git_version;
 use niri_config::Config;
 use smithay::output::Output;
 use smithay::reexports::rustix::time::{clock_gettime, ClockId};
-use smithay::utils::{Logical, Point, Rectangle, Size};
+use smithay::utils::{Logical, Point, Rectangle, Size, Transform};
 
-pub fn clone2<T: Clone, U: Clone>(t: (&T, &U)) -> (T, U) {
+pub mod id;
-    (t.0.clone(), t.1.clone())
+pub mod spawning;
+pub mod watcher;
+
+pub static IS_SYSTEMD_SERVICE: AtomicBool = AtomicBool::new(false);
+
+pub fn version() -> String {
+    format!(
+        "{} ({})",
+        env!("CARGO_PKG_VERSION"),
+        git_version!(fallback = "unknown commit"),
+    )
 }
 
 pub fn get_monotonic_time() -> Duration {
@@ -29,6 +37,10 @@ pub fn center(rect: Rectangle<i32, Logical>) -> Point<i32, Logical> {
     rect.loc + rect.size.downscale(2).to_point()
 }
 
+pub fn center_f64(rect: Rectangle<f64, Logical>) -> Point<f64, Logical> {
+    rect.loc + rect.size.downscale(2.0).to_point()
+}
+
 pub fn output_size(output: &Output) -> Size<i32, Logical> {
     let output_scale = output.current_scale().integer_scale();
     let output_transform = output.current_transform();
@@ -39,6 +51,51 @@ pub fn output_size(output: &Output) -> Size<i32, Logical> {
         .to_logical(output_scale)
 }
 
+pub fn logical_output(output: &Output) -> niri_ipc::LogicalOutput {
+    let loc = output.current_location();
+    let size = output_size(output);
+    let transform = match output.current_transform() {
+        Transform::Normal => niri_ipc::Transform::Normal,
+        Transform::_90 => niri_ipc::Transform::_90,
+        Transform::_180 => niri_ipc::Transform::_180,
+        Transform::_270 => niri_ipc::Transform::_270,
+        Transform::Flipped => niri_ipc::Transform::Flipped,
+        Transform::Flipped90 => niri_ipc::Transform::Flipped90,
+        Transform::Flipped180 => niri_ipc::Transform::Flipped180,
+        Transform::Flipped270 => niri_ipc::Transform::Flipped270,
+    };
+    niri_ipc::LogicalOutput {
+        x: loc.x,
+        y: loc.y,
+        width: size.w as u32,
+        height: size.h as u32,
+        scale: output.current_scale().fractional_scale(),
+        transform,
+    }
+}
+
+pub fn ipc_transform_to_smithay(transform: niri_ipc::Transform) -> Transform {
+    match transform {
+        niri_ipc::Transform::Normal => Transform::Normal,
+        niri_ipc::Transform::_90 => Transform::_90,
+        niri_ipc::Transform::_180 => Transform::_180,
+        niri_ipc::Transform::_270 => Transform::_270,
+        niri_ipc::Transform::Flipped => Transform::Flipped,
+        niri_ipc::Transform::Flipped90 => Transform::Flipped90,
+        niri_ipc::Transform::Flipped180 => Transform::Flipped180,
+        niri_ipc::Transform::Flipped270 => Transform::Flipped270,
+    }
+}
+
+pub fn expand_home(path: &Path) -> anyhow::Result<Option<PathBuf>> {
+    if let Ok(rest) = path.strip_prefix("~") {
+        let dirs = UserDirs::new().context("error retrieving home directory")?;
+        Ok(Some([dirs.home_dir(), rest].iter().collect()))
+    } else {
+        Ok(None)
+    }
+}
+
 pub fn make_screenshot_path(config: &Config) -> anyhow::Result<Option<PathBuf>> {
     let Some(path) = &config.screenshot_path else {
         return Ok(None);
@@ -61,91 +118,13 @@ pub fn make_screenshot_path(config: &Config) -> anyhow::Result<Option<PathBuf>>
         path = PathBuf::from(OsStr::from_bytes(&buf[..rv]));
     }
 
-    if let Ok(rest) = path.strip_prefix("~") {
+    if let Some(expanded) = expand_home(&path).context("error expanding ~")? {
-        let dirs = UserDirs::new().context("error retrieving home directory")?;
+        path = expanded;
-        path = [dirs.home_dir(), rest].iter().collect();
     }
 
     Ok(Some(path))
 }
 
-pub static REMOVE_ENV_RUST_BACKTRACE: AtomicBool = AtomicBool::new(false);
-pub static REMOVE_ENV_RUST_LIB_BACKTRACE: AtomicBool = AtomicBool::new(false);
-
-/// Spawns the command to run independently of the compositor.
-pub fn spawn<T: AsRef<OsStr> + Send + 'static>(command: Vec<T>) {
-    let _span = tracy_client::span!();
-
-    if command.is_empty() {
-        return;
-    }
-
-    // Spawning and waiting takes some milliseconds, so do it in a thread.
-    let res = thread::Builder::new()
-        .name("Command Spawner".to_owned())
-        .spawn(move || {
-            let (command, args) = command.split_first().unwrap();
-            spawn_sync(command, args);
-        });
-
-    if let Err(err) = res {
-        warn!("error spawning a thread to spawn the command: {err:?}");
-    }
-}
-
-fn spawn_sync(command: impl AsRef<OsStr>, args: impl IntoIterator<Item = impl AsRef<OsStr>>) {
-    let _span = tracy_client::span!();
-
-    let command = command.as_ref();
-
-    let mut process = Command::new(command);
-    process
-        .args(args)
-        .stdin(Stdio::null())
-        .stdout(Stdio::null())
-        .stderr(Stdio::null());
-
-    // Remove RUST_BACKTRACE and RUST_LIB_BACKTRACE from the environment if needed.
-    if REMOVE_ENV_RUST_BACKTRACE.load(Ordering::Relaxed) {
-        process.env_remove("RUST_BACKTRACE");
-    }
-    if REMOVE_ENV_RUST_LIB_BACKTRACE.load(Ordering::Relaxed) {
-        process.env_remove("RUST_LIB_BACKTRACE");
-    }
-
-    // Double-fork to avoid having to waitpid the child.
-    unsafe {
-        process.pre_exec(|| {
-            match libc::fork() {
-                -1 => return Err(io::Error::last_os_error()),
-                0 => (),
-                _ => libc::_exit(0),
-            }
-
-            Ok(())
-        });
-    }
-
-    let mut child = match process.spawn() {
-        Ok(child) => child,
-        Err(err) => {
-            warn!("error spawning {command:?}: {err:?}");
-            return;
-        }
-    };
-
-    match child.wait() {
-        Ok(status) => {
-            if !status.success() {
-                warn!("child did not exit successfully: {status:?}");
-            }
-        }
-        Err(err) => {
-            warn!("error waiting for child: {err:?}");
-        }
-    }
-}
-
 pub fn write_png_rgba8(
     w: impl Write,
     width: u32,

src/utils/spawning.rs

@@ -0,0 +1,378 @@
+use std::ffi::OsStr;
+use std::os::unix::process::CommandExt;
+use std::path::Path;
+use std::process::{Child, Command, Stdio};
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::RwLock;
+use std::{io, thread};
+
+use niri_config::Environment;
+
+use crate::utils::expand_home;
+
+pub static REMOVE_ENV_RUST_BACKTRACE: AtomicBool = AtomicBool::new(false);
+pub static REMOVE_ENV_RUST_LIB_BACKTRACE: AtomicBool = AtomicBool::new(false);
+pub static CHILD_ENV: RwLock<Environment> = RwLock::new(Environment(Vec::new()));
+
+/// Spawns the command to run independently of the compositor.
+pub fn spawn<T: AsRef<OsStr> + Send + 'static>(command: Vec<T>) {
+    let _span = tracy_client::span!();
+
+    if command.is_empty() {
+        return;
+    }
+
+    // Spawning and waiting takes some milliseconds, so do it in a thread.
+    let res = thread::Builder::new()
+        .name("Command Spawner".to_owned())
+        .spawn(move || {
+            let (command, args) = command.split_first().unwrap();
+            spawn_sync(command, args);
+        });
+
+    if let Err(err) = res {
+        warn!("error spawning a thread to spawn the command: {err:?}");
+    }
+}
+
+fn spawn_sync(command: impl AsRef<OsStr>, args: impl IntoIterator<Item = impl AsRef<OsStr>>) {
+    let _span = tracy_client::span!();
+
+    let mut command = command.as_ref();
+
+    // Expand `~` at the start.
+    let expanded = expand_home(Path::new(command));
+    match &expanded {
+        Ok(Some(expanded)) => command = expanded.as_ref(),
+        Ok(None) => (),
+        Err(err) => {
+            warn!("error expanding ~: {err:?}");
+        }
+    }
+
+    let mut process = Command::new(command);
+    process
+        .args(args)
+        .stdin(Stdio::null())
+        .stdout(Stdio::null())
+        .stderr(Stdio::null());
+
+    // Remove RUST_BACKTRACE and RUST_LIB_BACKTRACE from the environment if needed.
+    if REMOVE_ENV_RUST_BACKTRACE.load(Ordering::Relaxed) {
+        process.env_remove("RUST_BACKTRACE");
+    }
+    if REMOVE_ENV_RUST_LIB_BACKTRACE.load(Ordering::Relaxed) {
+        process.env_remove("RUST_LIB_BACKTRACE");
+    }
+
+    // Set configured environment.
+    let env = CHILD_ENV.read().unwrap();
+    for var in &env.0 {
+        if let Some(value) = &var.value {
+            process.env(&var.name, value);
+        } else {
+            process.env_remove(&var.name);
+        }
+    }
+    drop(env);
+
+    let Some(mut child) = do_spawn(command, process) else {
+        return;
+    };
+
+    match child.wait() {
+        Ok(status) => {
+            if !status.success() {
+                warn!("child did not exit successfully: {status:?}");
+            }
+        }
+        Err(err) => {
+            warn!("error waiting for child: {err:?}");
+        }
+    }
+}
+
+#[cfg(not(feature = "systemd"))]
+fn do_spawn(command: &OsStr, mut process: Command) -> Option<Child> {
+    unsafe {
+        // Double-fork to avoid having to waitpid the child.
+        process.pre_exec(move || {
+            match libc::fork() {
+                -1 => return Err(io::Error::last_os_error()),
+                0 => (),
+                _ => libc::_exit(0),
+            }
+
+            Ok(())
+        });
+    }
+
+    let child = match process.spawn() {
+        Ok(child) => child,
+        Err(err) => {
+            warn!("error spawning {command:?}: {err:?}");
+            return None;
+        }
+    };
+
+    Some(child)
+}
+
+#[cfg(feature = "systemd")]
+use systemd::do_spawn;
+
+#[cfg(feature = "systemd")]
+mod systemd {
+    use std::os::fd::{AsFd, AsRawFd, FromRawFd, OwnedFd};
+
+    use smithay::reexports::rustix;
+    use smithay::reexports::rustix::io::{close, read, retry_on_intr, write};
+    use smithay::reexports::rustix::pipe::{pipe_with, PipeFlags};
+
+    use super::*;
+
+    pub fn do_spawn(command: &OsStr, mut process: Command) -> Option<Child> {
+        use libc::close_range;
+
+        // When running as a systemd session, we want to put children into their own transient
+        // scopes in order to separate them from the niri process. This is helpful for
+        // example to prevent the OOM killer from taking down niri together with a
+        // misbehaving client.
+        //
+        // Putting a child into a scope is done by calling systemd's StartTransientUnit D-Bus method
+        // with a PID. Unfortunately, there seems to be a race in systemd where if the child exits
+        // at just the right time, the transient unit will be created but empty, so it will
+        // linger around forever.
+        //
+        // To prevent this, we'll use our double-fork (done for a separate reason) to help. In our
+        // intermediate child we will send back the grandchild PID, and in niri we will create a
+        // transient scope with both our intermediate child and the grandchild PIDs set. Only then
+        // we will signal our intermediate child to exit. This way, even if the grandchild
+        // exits quickly, a non-empty scope will be created (with just our intermediate
+        // child), then cleaned up when our intermediate child exits.
+
+        // Make a pipe to receive the grandchild PID.
+
+        let (pipe_pid_read, pipe_pid_write) = pipe_with(PipeFlags::CLOEXEC)
+            .map_err(|err| {
+                warn!("error creating a pipe to transfer child PID: {err:?}");
+            })
+            .ok()
+            .unzip();
+        // Make a pipe to wait in the intermediate child.
+        let (pipe_wait_read, pipe_wait_write) = pipe_with(PipeFlags::CLOEXEC)
+            .map_err(|err| {
+                warn!("error creating a pipe for child to wait on: {err:?}");
+            })
+            .ok()
+            .unzip();
+
+        unsafe {
+            // The fds will be duplicated after a fork and closed on exec or exit automatically. Get
+            // the raw fd inside so that it's not closed any extra times.
+            let mut pipe_pid_read_fd = pipe_pid_read.as_ref().map(|fd| fd.as_raw_fd());
+            let mut pipe_pid_write_fd = pipe_pid_write.as_ref().map(|fd| fd.as_raw_fd());
+            let mut pipe_wait_read_fd = pipe_wait_read.as_ref().map(|fd| fd.as_raw_fd());
+            let mut pipe_wait_write_fd = pipe_wait_write.as_ref().map(|fd| fd.as_raw_fd());
+
+            // Double-fork to avoid having to waitpid the child.
+            process.pre_exec(move || {
+                // Close FDs that we don't need. Especially important for the write ones to unblock
+                // the readers.
+                if let Some(fd) = pipe_pid_read_fd.take() {
+                    close(fd);
+                }
+                if let Some(fd) = pipe_wait_write_fd.take() {
+                    close(fd);
+                }
+
+                // Convert the our FDs to OwnedFd, which will close them in all of our fork paths.
+                let pipe_pid_write = pipe_pid_write_fd.take().map(|fd| OwnedFd::from_raw_fd(fd));
+                let pipe_wait_read = pipe_wait_read_fd.take().map(|fd| OwnedFd::from_raw_fd(fd));
+
+                match libc::fork() {
+                    -1 => return Err(io::Error::last_os_error()),
+                    0 => (),
+                    grandchild_pid => {
+                        // Send back the PID.
+                        if let Some(pipe) = pipe_pid_write {
+                            let _ = write_all(pipe, &grandchild_pid.to_ne_bytes());
+                        }
+
+                        // Wait until the parent signals us to exit.
+                        if let Some(pipe) = pipe_wait_read {
+                            // We're going to exit afterwards. Close all other FDs to allow
+                            // Command::spawn() to return in the parent process.
+                            let raw = pipe.as_raw_fd() as u32;
+                            let _ = close_range(0, raw - 1, 0);
+                            let _ = close_range(raw + 1, !0, 0);
+
+                            let _ = read_all(pipe, &mut [0]);
+                        }
+
+                        libc::_exit(0)
+                    }
+                }
+
+                Ok(())
+            });
+        }
+
+        let child = match process.spawn() {
+            Ok(child) => child,
+            Err(err) => {
+                warn!("error spawning {command:?}: {err:?}");
+                return None;
+            }
+        };
+
+        drop(pipe_pid_write);
+        drop(pipe_wait_read);
+
+        // Wait for the grandchild PID.
+        if let Some(pipe) = pipe_pid_read {
+            let mut buf = [0; 4];
+            match read_all(pipe, &mut buf) {
+                Ok(()) => {
+                    let pid = i32::from_ne_bytes(buf);
+                    trace!("spawned PID: {pid}");
+
+                    // Start a systemd scope for the grandchild.
+                    #[cfg(feature = "systemd")]
+                    if let Err(err) = start_systemd_scope(command, child.id(), pid as u32) {
+                        trace!("error starting systemd scope for spawned command: {err:?}");
+                    }
+                }
+                Err(err) => {
+                    warn!("error reading child PID: {err:?}");
+                }
+            }
+        }
+
+        // Signal the intermediate child to exit now that we're done trying to creating a systemd
+        // scope.
+        trace!("signaling child to exit");
+        drop(pipe_wait_write);
+
+        Some(child)
+    }
+
+    #[cfg(feature = "systemd")]
+    fn write_all(fd: impl AsFd, buf: &[u8]) -> rustix::io::Result<()> {
+        let mut written = 0;
+        loop {
+            let n = retry_on_intr(|| write(&fd, &buf[written..]))?;
+            if n == 0 {
+                return Err(rustix::io::Errno::CANCELED);
+            }
+
+            written += n;
+            if written == buf.len() {
+                return Ok(());
+            }
+        }
+    }
+
+    #[cfg(feature = "systemd")]
+    fn read_all(fd: impl AsFd, buf: &mut [u8]) -> rustix::io::Result<()> {
+        let mut start = 0;
+        loop {
+            let n = retry_on_intr(|| read(&fd, &mut buf[start..]))?;
+            if n == 0 {
+                return Err(rustix::io::Errno::CANCELED);
+            }
+
+            start += n;
+            if start == buf.len() {
+                return Ok(());
+            }
+        }
+    }
+
+    /// Puts a (newly spawned) pid into a transient systemd scope.
+    ///
+    /// This separates the pid from the compositor scope, which for example prevents the OOM killer
+    /// from bringing down the compositor together with a misbehaving client.
+    #[cfg(feature = "systemd")]
+    fn start_systemd_scope(
+        name: &OsStr,
+        intermediate_pid: u32,
+        child_pid: u32,
+    ) -> anyhow::Result<()> {
+        use std::fmt::Write as _;
+        use std::os::unix::ffi::OsStrExt;
+        use std::sync::OnceLock;
+
+        use anyhow::Context;
+        use zbus::zvariant::{OwnedObjectPath, Value};
+
+        use crate::utils::IS_SYSTEMD_SERVICE;
+
+        // We only start transient scopes if we're a systemd service ourselves.
+        if !IS_SYSTEMD_SERVICE.load(Ordering::Relaxed) {
+            return Ok(());
+        }
+
+        let _span = tracy_client::span!();
+
+        // Extract the basename.
+        let name = Path::new(name).file_name().unwrap_or(name);
+
+        let mut scope_name = String::from("app-niri-");
+
+        // Escape for systemd similarly to libgnome-desktop, which says it had adapted this from
+        // systemd source.
+        for &c in name.as_bytes() {
+            if c.is_ascii_alphanumeric() || matches!(c, b':' | b'_' | b'.') {
+                scope_name.push(char::from(c));
+            } else {
+                let _ = write!(scope_name, "\\x{c:02x}");
+            }
+        }
+
+        let _ = write!(scope_name, "-{child_pid}.scope");
+
+        // Ask systemd to start a transient scope.
+        static CONNECTION: OnceLock<zbus::Result<zbus::blocking::Connection>> = OnceLock::new();
+        let conn = CONNECTION
+            .get_or_init(zbus::blocking::Connection::session)
+            .clone()
+            .context("error connecting to session bus")?;
+
+        let proxy = zbus::blocking::Proxy::new(
+            &conn,
+            "org.freedesktop.systemd1",
+            "/org/freedesktop/systemd1",
+            "org.freedesktop.systemd1.Manager",
+        )
+        .context("error creating a Proxy")?;
+
+        let signals = proxy
+            .receive_signal("JobRemoved")
+            .context("error creating a signal iterator")?;
+
+        let pids: &[_] = &[intermediate_pid, child_pid];
+        let properties: &[_] = &[
+            ("PIDs", Value::new(pids)),
+            ("CollectMode", Value::new("inactive-or-failed")),
+        ];
+        let aux: &[(&str, &[(&str, Value)])] = &[];
+
+        let job: OwnedObjectPath = proxy
+            .call("StartTransientUnit", &(scope_name, "fail", properties, aux))
+            .context("error calling StartTransientUnit")?;
+
+        trace!("waiting for JobRemoved");
+        for message in signals {
+            let body: (u32, OwnedObjectPath, &str, &str) =
+                message.body().context("error parsing signal")?;
+
+            if body.1 == job {
+                // Our transient unit had started, we're good to exit the intermediate child.
+                break;
+            }
+        }
+
+        Ok(())
+    }
+}

src/utils/watcher.rs

@@ -0,0 +1,348 @@
+//! File modification watcher.
+
+use std::path::PathBuf;
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::{mpsc, Arc};
+use std::thread;
+use std::time::Duration;
+
+use smithay::reexports::calloop::channel::SyncSender;
+
+pub struct Watcher {
+    should_stop: Arc<AtomicBool>,
+}
+
+impl Drop for Watcher {
+    fn drop(&mut self) {
+        self.should_stop.store(true, Ordering::SeqCst);
+    }
+}
+
+impl Watcher {
+    pub fn new(path: PathBuf, changed: SyncSender<()>) -> Self {
+        Self::with_start_notification(path, changed, None)
+    }
+
+    pub fn with_start_notification(
+        path: PathBuf,
+        changed: SyncSender<()>,
+        started: Option<mpsc::SyncSender<()>>,
+    ) -> Self {
+        let should_stop = Arc::new(AtomicBool::new(false));
+
+        {
+            let should_stop = should_stop.clone();
+            thread::Builder::new()
+                .name(format!("Filesystem Watcher for {}", path.to_string_lossy()))
+                .spawn(move || {
+                    // this "should" be as simple as mtime, but it does not quite work in practice;
+                    // it doesn't work if the config is a symlink, and its target changes but the
+                    // new target and old target have identical mtimes.
+                    //
+                    // in practice, this does not occur on any systems other than nix.
+                    // because, on nix practically everything is a symlink to /nix/store
+                    // and due to reproducibility, /nix/store keeps no mtime (= 1970-01-01)
+                    // so, symlink targets change frequently when mtime doesn't.
+                    let mut last_props = path
+                        .canonicalize()
+                        .and_then(|canon| Ok((canon.metadata()?.modified()?, canon)))
+                        .ok();
+
+                    if let Some(started) = started {
+                        let _ = started.send(());
+                    }
+
+                    loop {
+                        thread::sleep(Duration::from_millis(500));
+
+                        if should_stop.load(Ordering::SeqCst) {
+                            break;
+                        }
+
+                        if let Ok(new_props) = path
+                            .canonicalize()
+                            .and_then(|canon| Ok((canon.metadata()?.modified()?, canon)))
+                        {
+                            if last_props.as_ref() != Some(&new_props) {
+                                trace!("file changed: {}", path.to_string_lossy());
+
+                                if let Err(err) = changed.send(()) {
+                                    warn!("error sending change notification: {err:?}");
+                                    break;
+                                }
+
+                                last_props = Some(new_props);
+                            }
+                        }
+                    }
+
+                    debug!("exiting watcher thread for {}", path.to_string_lossy());
+                })
+                .unwrap();
+        }
+
+        Self { should_stop }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::error::Error;
+    use std::fs::File;
+    use std::io::Write;
+    use std::sync::atomic::AtomicU8;
+
+    use calloop::channel::sync_channel;
+    use calloop::EventLoop;
+    use smithay::reexports::rustix::fs::{futimens, Timestamps};
+    use smithay::reexports::rustix::time::Timespec;
+    use xshell::{cmd, Shell};
+
+    use super::*;
+
+    fn check(
+        setup: impl FnOnce(&Shell) -> Result<(), Box<dyn Error>>,
+        change: impl FnOnce(&Shell) -> Result<(), Box<dyn Error>>,
+    ) {
+        let sh = Shell::new().unwrap();
+        let temp_dir = sh.create_temp_dir().unwrap();
+        sh.change_dir(temp_dir.path());
+        // let dir = sh.create_dir("xshell").unwrap();
+        // sh.change_dir(dir);
+
+        let mut config_path = sh.current_dir();
+        config_path.push("niri");
+        config_path.push("config.kdl");
+
+        setup(&sh).unwrap();
+
+        let changed = AtomicU8::new(0);
+
+        let mut event_loop = EventLoop::try_new().unwrap();
+        let loop_handle = event_loop.handle();
+
+        let (tx, rx) = sync_channel(1);
+        let (started_tx, started_rx) = mpsc::sync_channel(1);
+        let _watcher = Watcher::with_start_notification(config_path.clone(), tx, Some(started_tx));
+        loop_handle
+            .insert_source(rx, |_, _, _| {
+                changed.fetch_add(1, Ordering::SeqCst);
+            })
+            .unwrap();
+        started_rx.recv().unwrap();
+
+        // HACK: if we don't sleep, files might have the same mtime.
+        thread::sleep(Duration::from_millis(100));
+
+        change(&sh).unwrap();
+
+        event_loop
+            .dispatch(Duration::from_millis(750), &mut ())
+            .unwrap();
+
+        assert_eq!(changed.load(Ordering::SeqCst), 1);
+
+        // Verify that the watcher didn't break.
+        sh.write_file(&config_path, "c").unwrap();
+
+        event_loop
+            .dispatch(Duration::from_millis(750), &mut ())
+            .unwrap();
+
+        assert_eq!(changed.load(Ordering::SeqCst), 2);
+    }
+
+    #[test]
+    fn change_file() {
+        check(
+            |sh| {
+                sh.write_file("niri/config.kdl", "a")?;
+                Ok(())
+            },
+            |sh| {
+                sh.write_file("niri/config.kdl", "b")?;
+                Ok(())
+            },
+        );
+    }
+
+    #[test]
+    fn create_file() {
+        check(
+            |sh| {
+                sh.create_dir("niri")?;
+                Ok(())
+            },
+            |sh| {
+                sh.write_file("niri/config.kdl", "a")?;
+                Ok(())
+            },
+        );
+    }
+
+    #[test]
+    fn create_dir_and_file() {
+        check(
+            |_sh| Ok(()),
+            |sh| {
+                sh.write_file("niri/config.kdl", "a")?;
+                Ok(())
+            },
+        );
+    }
+
+    #[test]
+    fn change_linked_file() {
+        check(
+            |sh| {
+                sh.write_file("niri/config2.kdl", "a")?;
+                cmd!(sh, "ln -s config2.kdl niri/config.kdl").run()?;
+                Ok(())
+            },
+            |sh| {
+                sh.write_file("niri/config2.kdl", "b")?;
+                Ok(())
+            },
+        );
+    }
+
+    #[test]
+    fn change_file_in_linked_dir() {
+        check(
+            |sh| {
+                sh.write_file("niri2/config.kdl", "a")?;
+                cmd!(sh, "ln -s niri2 niri").run()?;
+                Ok(())
+            },
+            |sh| {
+                sh.write_file("niri2/config.kdl", "b")?;
+                Ok(())
+            },
+        );
+    }
+
+    #[test]
+    fn recreate_file() {
+        check(
+            |sh| {
+                sh.write_file("niri/config.kdl", "a")?;
+                Ok(())
+            },
+            |sh| {
+                sh.remove_path("niri/config.kdl")?;
+                sh.write_file("niri/config.kdl", "b")?;
+                Ok(())
+            },
+        );
+    }
+
+    #[test]
+    fn recreate_dir() {
+        check(
+            |sh| {
+                sh.write_file("niri/config.kdl", "a")?;
+                Ok(())
+            },
+            |sh| {
+                sh.remove_path("niri")?;
+                sh.write_file("niri/config.kdl", "b")?;
+                Ok(())
+            },
+        );
+    }
+
+    #[test]
+    fn swap_dir() {
+        check(
+            |sh| {
+                sh.write_file("niri/config.kdl", "a")?;
+                Ok(())
+            },
+            |sh| {
+                sh.write_file("niri2/config.kdl", "b")?;
+                sh.remove_path("niri")?;
+                cmd!(sh, "mv niri2 niri").run()?;
+                Ok(())
+            },
+        );
+    }
+
+    #[test]
+    fn swap_just_link() {
+        // NixOS setup: link path changes, mtime stays constant.
+        check(
+            |sh| {
+                let mut dir = sh.current_dir();
+                dir.push("niri");
+                sh.create_dir(&dir)?;
+
+                let mut d2 = dir.clone();
+                d2.push("config2.kdl");
+                let mut c2 = File::create(d2).unwrap();
+                write!(c2, "a")?;
+                c2.flush()?;
+                futimens(
+                    &c2,
+                    &Timestamps {
+                        last_access: Timespec {
+                            tv_sec: 0,
+                            tv_nsec: 0,
+                        },
+                        last_modification: Timespec {
+                            tv_sec: 0,
+                            tv_nsec: 0,
+                        },
+                    },
+                )?;
+                c2.sync_all()?;
+                drop(c2);
+
+                let mut d3 = dir.clone();
+                d3.push("config3.kdl");
+                let mut c3 = File::create(d3).unwrap();
+                write!(c3, "b")?;
+                c3.flush()?;
+                futimens(
+                    &c3,
+                    &Timestamps {
+                        last_access: Timespec {
+                            tv_sec: 0,
+                            tv_nsec: 0,
+                        },
+                        last_modification: Timespec {
+                            tv_sec: 0,
+                            tv_nsec: 0,
+                        },
+                    },
+                )?;
+                c3.sync_all()?;
+                drop(c3);
+
+                cmd!(sh, "ln -s config2.kdl niri/config.kdl").run()?;
+                Ok(())
+            },
+            |sh| {
+                cmd!(sh, "unlink niri/config.kdl").run()?;
+                cmd!(sh, "ln -s config3.kdl niri/config.kdl").run()?;
+                Ok(())
+            },
+        );
+    }
+
+    #[test]
+    fn swap_dir_link() {
+        check(
+            |sh| {
+                sh.write_file("niri2/config.kdl", "a")?;
+                cmd!(sh, "ln -s niri2 niri").run()?;
+                Ok(())
+            },
+            |sh| {
+                sh.write_file("niri3/config.kdl", "b")?;
+                cmd!(sh, "unlink niri").run()?;
+                cmd!(sh, "ln -s niri3 niri").run()?;
+                Ok(())
+            },
+        );
+    }
+}

src/watcher.rs

@@ -1,60 +0,0 @@
-//! File modification watcher.
-
-use std::path::PathBuf;
-use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::Arc;
-use std::thread;
-use std::time::Duration;
-
-use smithay::reexports::calloop::channel::SyncSender;
-
-pub struct Watcher {
-    should_stop: Arc<AtomicBool>,
-}
-
-impl Drop for Watcher {
-    fn drop(&mut self) {
-        self.should_stop.store(true, Ordering::SeqCst);
-    }
-}
-
-impl Watcher {
-    pub fn new(path: PathBuf, changed: SyncSender<()>) -> Self {
-        let should_stop = Arc::new(AtomicBool::new(false));
-
-        {
-            let should_stop = should_stop.clone();
-            thread::Builder::new()
-                .name(format!("Filesystem Watcher for {}", path.to_string_lossy()))
-                .spawn(move || {
-                    let mut last_mtime = path.metadata().and_then(|meta| meta.modified()).ok();
-
-                    loop {
-                        thread::sleep(Duration::from_millis(500));
-
-                        if should_stop.load(Ordering::SeqCst) {
-                            break;
-                        }
-
-                        if let Ok(mtime) = path.metadata().and_then(|meta| meta.modified()) {
-                            if last_mtime != Some(mtime) {
-                                trace!("file changed: {}", path.to_string_lossy());
-
-                                if let Err(err) = changed.send(()) {
-                                    warn!("error sending change notification: {err:?}");
-                                    break;
-                                }
-
-                                last_mtime = Some(mtime);
-                            }
-                        }
-                    }
-
-                    debug!("exiting watcher thread for {}", path.to_string_lossy());
-                })
-                .unwrap();
-        }
-
-        Self { should_stop }
-    }
-}

src/window/mapped.rs

@@ -0,0 +1,394 @@
+use std::cell::RefCell;
+use std::cmp::{max, min};
+
+use niri_config::{BlockOutFrom, WindowRule};
+use smithay::backend::renderer::element::solid::{SolidColorBuffer, SolidColorRenderElement};
+use smithay::backend::renderer::element::{AsRenderElements, Id, Kind};
+use smithay::backend::renderer::gles::GlesRenderer;
+use smithay::desktop::space::SpaceElement as _;
+use smithay::desktop::{PopupManager, Window};
+use smithay::output::Output;
+use smithay::reexports::wayland_protocols::xdg::decoration::zv1::server::zxdg_toplevel_decoration_v1;
+use smithay::reexports::wayland_protocols::xdg::shell::server::xdg_toplevel;
+use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
+use smithay::utils::{Logical, Point, Rectangle, Scale, Serial, Size, Transform};
+use smithay::wayland::compositor::{
+    remove_pre_commit_hook, send_surface_state, with_states, HookId,
+};
+use smithay::wayland::shell::xdg::{SurfaceCachedState, ToplevelSurface};
+
+use super::{ResolvedWindowRules, WindowRef};
+use crate::layout::{LayoutElement, LayoutElementRenderElement, LayoutElementRenderSnapshot};
+use crate::niri::WindowOffscreenId;
+use crate::render_helpers::renderer::NiriRenderer;
+use crate::render_helpers::snapshot::RenderSnapshot;
+use crate::render_helpers::surface::render_snapshot_from_surface_tree;
+use crate::render_helpers::{BakedBuffer, RenderTarget};
+
+#[derive(Debug)]
+pub struct Mapped {
+    pub window: Window,
+
+    /// Pre-commit hook that we have on all mapped toplevel surfaces.
+    pre_commit_hook: HookId,
+
+    /// Up-to-date rules.
+    rules: ResolvedWindowRules,
+
+    /// Whether the window rules need to be recomputed.
+    ///
+    /// This is not used in all cases; for example, app ID and title changes recompute the rules
+    /// immediately, rather than setting this flag.
+    need_to_recompute_rules: bool,
+
+    /// Whether this window has the keyboard focus.
+    is_focused: bool,
+
+    /// Buffer to draw instead of the window when it should be blocked out.
+    block_out_buffer: RefCell<SolidColorBuffer>,
+
+    /// Snapshot of the last render for use in the close animation.
+    unmap_snapshot: RefCell<Option<LayoutElementRenderSnapshot>>,
+
+    /// Whether the next configure should be animated, if the configured state changed.
+    animate_next_configure: bool,
+
+    /// Serials of commits that should be animated.
+    animate_serials: Vec<Serial>,
+
+    /// Snapshot right before an animated commit.
+    animation_snapshot: Option<LayoutElementRenderSnapshot>,
+}
+
+impl Mapped {
+    pub fn new(window: Window, rules: ResolvedWindowRules, hook: HookId) -> Self {
+        Self {
+            window,
+            pre_commit_hook: hook,
+            rules,
+            need_to_recompute_rules: false,
+            is_focused: false,
+            block_out_buffer: RefCell::new(SolidColorBuffer::new((0, 0), [0., 0., 0., 1.])),
+            unmap_snapshot: RefCell::new(None),
+            animate_next_configure: false,
+            animate_serials: Vec::new(),
+            animation_snapshot: None,
+        }
+    }
+
+    pub fn toplevel(&self) -> &ToplevelSurface {
+        self.window.toplevel().expect("no X11 support")
+    }
+
+    /// Recomputes the resolved window rules and returns whether they changed.
+    pub fn recompute_window_rules(&mut self, rules: &[WindowRule]) -> bool {
+        self.need_to_recompute_rules = false;
+
+        let new_rules = ResolvedWindowRules::compute(rules, WindowRef::Mapped(self));
+        if new_rules == self.rules {
+            return false;
+        }
+
+        self.rules = new_rules;
+        true
+    }
+
+    pub fn recompute_window_rules_if_needed(&mut self, rules: &[WindowRule]) -> bool {
+        if !self.need_to_recompute_rules {
+            return false;
+        }
+
+        self.recompute_window_rules(rules)
+    }
+
+    pub fn is_focused(&self) -> bool {
+        self.is_focused
+    }
+
+    pub fn set_is_focused(&mut self, is_focused: bool) {
+        if self.is_focused == is_focused {
+            return;
+        }
+
+        self.is_focused = is_focused;
+        self.need_to_recompute_rules = true;
+    }
+
+    fn render_snapshot(&self, renderer: &mut GlesRenderer) -> LayoutElementRenderSnapshot {
+        let _span = tracy_client::span!("Mapped::render_snapshot");
+
+        let size = self.size();
+
+        let mut buffer = self.block_out_buffer.borrow_mut();
+        buffer.resize(size);
+        let blocked_out_contents = vec![BakedBuffer {
+            buffer: buffer.clone(),
+            location: Point::from((0, 0)),
+            src: None,
+            dst: None,
+        }];
+
+        let buf_pos = self.window.geometry().loc.upscale(-1);
+
+        let mut contents = vec![];
+
+        let surface = self.toplevel().wl_surface();
+        for (popup, popup_offset) in PopupManager::popups_for_surface(surface) {
+            let offset = self.window.geometry().loc + popup_offset - popup.geometry().loc;
+
+            render_snapshot_from_surface_tree(
+                renderer,
+                popup.wl_surface(),
+                buf_pos + offset,
+                &mut contents,
+            );
+        }
+
+        render_snapshot_from_surface_tree(renderer, surface, buf_pos, &mut contents);
+
+        RenderSnapshot {
+            contents,
+            blocked_out_contents,
+            block_out_from: self.rules().block_out_from,
+            size,
+            texture: Default::default(),
+            blocked_out_texture: Default::default(),
+        }
+    }
+
+    pub fn store_unmap_snapshot_if_empty(&self, renderer: &mut GlesRenderer) {
+        let mut snapshot = self.unmap_snapshot.borrow_mut();
+        if snapshot.is_some() {
+            return;
+        }
+
+        *snapshot = Some(self.render_snapshot(renderer));
+    }
+
+    pub fn should_animate_commit(&mut self, commit_serial: Serial) -> bool {
+        let mut should_animate = false;
+        self.animate_serials.retain_mut(|serial| {
+            if commit_serial.is_no_older_than(serial) {
+                should_animate = true;
+                false
+            } else {
+                true
+            }
+        });
+        should_animate
+    }
+
+    pub fn store_animation_snapshot(&mut self, renderer: &mut GlesRenderer) {
+        self.animation_snapshot = Some(self.render_snapshot(renderer));
+    }
+}
+
+impl Drop for Mapped {
+    fn drop(&mut self) {
+        remove_pre_commit_hook(self.toplevel().wl_surface(), self.pre_commit_hook);
+    }
+}
+
+impl LayoutElement for Mapped {
+    type Id = Window;
+
+    fn id(&self) -> &Self::Id {
+        &self.window
+    }
+
+    fn size(&self) -> Size<i32, Logical> {
+        self.window.geometry().size
+    }
+
+    fn buf_loc(&self) -> Point<i32, Logical> {
+        Point::from((0, 0)) - self.window.geometry().loc
+    }
+
+    fn is_in_input_region(&self, point: Point<f64, Logical>) -> bool {
+        let surface_local = point + self.window.geometry().loc.to_f64();
+        self.window.is_in_input_region(&surface_local)
+    }
+
+    fn render<R: NiriRenderer>(
+        &self,
+        renderer: &mut R,
+        location: Point<i32, Logical>,
+        scale: Scale<f64>,
+        alpha: f32,
+        target: RenderTarget,
+    ) -> Vec<LayoutElementRenderElement<R>> {
+        let block_out = match self.rules.block_out_from {
+            None => false,
+            Some(BlockOutFrom::Screencast) => target == RenderTarget::Screencast,
+            Some(BlockOutFrom::ScreenCapture) => target != RenderTarget::Output,
+        };
+
+        if block_out {
+            let mut buffer = self.block_out_buffer.borrow_mut();
+            buffer.resize(self.window.geometry().size);
+            let elem = SolidColorRenderElement::from_buffer(
+                &buffer,
+                location.to_physical_precise_round(scale),
+                scale,
+                alpha,
+                Kind::Unspecified,
+            );
+            vec![elem.into()]
+        } else {
+            let buf_pos = location - self.window.geometry().loc;
+            let buf_pos = buf_pos.to_physical_precise_round(scale);
+            self.window.render_elements(renderer, buf_pos, scale, alpha)
+        }
+    }
+
+    fn request_size(&mut self, size: Size<i32, Logical>, animate: bool) {
+        let changed = self.toplevel().with_pending_state(|state| {
+            let changed = state.size != Some(size);
+            state.size = Some(size);
+            state.states.unset(xdg_toplevel::State::Fullscreen);
+            changed
+        });
+
+        if changed && animate {
+            self.animate_next_configure = true;
+        }
+    }
+
+    fn request_fullscreen(&self, size: Size<i32, Logical>) {
+        self.toplevel().with_pending_state(|state| {
+            state.size = Some(size);
+            state.states.set(xdg_toplevel::State::Fullscreen);
+        });
+    }
+
+    fn min_size(&self) -> Size<i32, Logical> {
+        let mut size = with_states(self.toplevel().wl_surface(), |state| {
+            let curr = state.cached_state.current::<SurfaceCachedState>();
+            curr.min_size
+        });
+
+        if let Some(x) = self.rules.min_width {
+            size.w = max(size.w, i32::from(x));
+        }
+        if let Some(x) = self.rules.min_height {
+            size.h = max(size.h, i32::from(x));
+        }
+
+        size
+    }
+
+    fn max_size(&self) -> Size<i32, Logical> {
+        let mut size = with_states(self.toplevel().wl_surface(), |state| {
+            let curr = state.cached_state.current::<SurfaceCachedState>();
+            curr.max_size
+        });
+
+        if let Some(x) = self.rules.max_width {
+            if size.w == 0 {
+                size.w = i32::from(x);
+            } else if x > 0 {
+                size.w = min(size.w, i32::from(x));
+            }
+        }
+        if let Some(x) = self.rules.max_height {
+            if size.h == 0 {
+                size.h = i32::from(x);
+            } else if x > 0 {
+                size.h = min(size.h, i32::from(x));
+            }
+        }
+
+        size
+    }
+
+    fn is_wl_surface(&self, wl_surface: &WlSurface) -> bool {
+        self.toplevel().wl_surface() == wl_surface
+    }
+
+    fn set_preferred_scale_transform(&self, scale: i32, transform: Transform) {
+        self.window.with_surfaces(|surface, data| {
+            send_surface_state(surface, data, scale, transform);
+        });
+    }
+
+    fn has_ssd(&self) -> bool {
+        self.toplevel().current_state().decoration_mode
+            == Some(zxdg_toplevel_decoration_v1::Mode::ServerSide)
+    }
+
+    fn output_enter(&self, output: &Output) {
+        let overlap = Rectangle::from_loc_and_size((0, 0), (i32::MAX, i32::MAX));
+        self.window.output_enter(output, overlap)
+    }
+
+    fn output_leave(&self, output: &Output) {
+        self.window.output_leave(output)
+    }
+
+    fn set_offscreen_element_id(&self, id: Option<Id>) {
+        let data = self
+            .window
+            .user_data()
+            .get_or_insert(WindowOffscreenId::default);
+        data.0.replace(id);
+    }
+
+    fn set_activated(&mut self, active: bool) {
+        let changed = self.toplevel().with_pending_state(|state| {
+            if active {
+                state.states.set(xdg_toplevel::State::Activated)
+            } else {
+                state.states.unset(xdg_toplevel::State::Activated)
+            }
+        });
+        self.need_to_recompute_rules |= changed;
+    }
+
+    fn set_bounds(&self, bounds: Size<i32, Logical>) {
+        self.toplevel().with_pending_state(|state| {
+            state.bounds = Some(bounds);
+        });
+    }
+
+    fn send_pending_configure(&mut self) {
+        if let Some(serial) = self.toplevel().send_pending_configure() {
+            if self.animate_next_configure {
+                self.animate_serials.push(serial);
+            }
+        }
+
+        self.animate_next_configure = false;
+    }
+
+    fn is_fullscreen(&self) -> bool {
+        self.toplevel()
+            .current_state()
+            .states
+            .contains(xdg_toplevel::State::Fullscreen)
+    }
+
+    fn is_pending_fullscreen(&self) -> bool {
+        self.toplevel()
+            .with_pending_state(|state| state.states.contains(xdg_toplevel::State::Fullscreen))
+    }
+
+    fn refresh(&self) {
+        self.window.refresh();
+    }
+
+    fn rules(&self) -> &ResolvedWindowRules {
+        &self.rules
+    }
+
+    fn take_unmap_snapshot(&self) -> Option<LayoutElementRenderSnapshot> {
+        self.unmap_snapshot.take()
+    }
+
+    fn animation_snapshot(&self) -> Option<&LayoutElementRenderSnapshot> {
+        self.animation_snapshot.as_ref()
+    }
+
+    fn take_animation_snapshot(&mut self) -> Option<LayoutElementRenderSnapshot> {
+        self.animation_snapshot.take()
+    }
+}

src/window/mod.rs

@@ -0,0 +1,218 @@
+use niri_config::{BlockOutFrom, Match, WindowRule};
+use smithay::reexports::wayland_protocols::xdg::shell::server::xdg_toplevel;
+use smithay::wayland::compositor::with_states;
+use smithay::wayland::shell::xdg::{
+    ToplevelSurface, XdgToplevelSurfaceData, XdgToplevelSurfaceRoleAttributes,
+};
+
+use crate::layout::workspace::ColumnWidth;
+
+pub mod mapped;
+pub use mapped::Mapped;
+
+pub mod unmapped;
+pub use unmapped::{InitialConfigureState, Unmapped};
+
+/// Reference to a mapped or unmapped window.
+#[derive(Debug, Clone, Copy)]
+pub enum WindowRef<'a> {
+    Unmapped(&'a Unmapped),
+    Mapped(&'a Mapped),
+}
+
+/// Rules fully resolved for a window.
+#[derive(Debug, PartialEq)]
+pub struct ResolvedWindowRules {
+    /// Default width for this window.
+    ///
+    /// - `None`: unset (global default should be used).
+    /// - `Some(None)`: set to empty (window picks its own width).
+    /// - `Some(Some(width))`: set to a particular width.
+    pub default_width: Option<Option<ColumnWidth>>,
+
+    /// Output to open this window on.
+    pub open_on_output: Option<String>,
+
+    /// Whether the window should open full-width.
+    pub open_maximized: Option<bool>,
+
+    /// Whether the window should open fullscreen.
+    pub open_fullscreen: Option<bool>,
+
+    /// Extra bound on the minimum window width.
+    pub min_width: Option<u16>,
+    /// Extra bound on the minimum window height.
+    pub min_height: Option<u16>,
+    /// Extra bound on the maximum window width.
+    pub max_width: Option<u16>,
+    /// Extra bound on the maximum window height.
+    pub max_height: Option<u16>,
+
+    /// Whether or not to draw the border with a solid background.
+    ///
+    /// `None` means using the SSD heuristic.
+    pub draw_border_with_background: Option<bool>,
+
+    /// Extra opacity to draw this window with.
+    pub opacity: Option<f32>,
+
+    /// Whether to block out this window from certain render targets.
+    pub block_out_from: Option<BlockOutFrom>,
+}
+
+impl<'a> WindowRef<'a> {
+    pub fn toplevel(self) -> &'a ToplevelSurface {
+        match self {
+            WindowRef::Unmapped(unmapped) => unmapped.toplevel(),
+            WindowRef::Mapped(mapped) => mapped.toplevel(),
+        }
+    }
+
+    pub fn is_focused(self) -> bool {
+        match self {
+            WindowRef::Unmapped(_) => false,
+            WindowRef::Mapped(mapped) => mapped.is_focused(),
+        }
+    }
+}
+
+impl ResolvedWindowRules {
+    pub const fn empty() -> Self {
+        Self {
+            default_width: None,
+            open_on_output: None,
+            open_maximized: None,
+            open_fullscreen: None,
+            min_width: None,
+            min_height: None,
+            max_width: None,
+            max_height: None,
+            draw_border_with_background: None,
+            opacity: None,
+            block_out_from: None,
+        }
+    }
+
+    pub fn compute(rules: &[WindowRule], window: WindowRef) -> Self {
+        let _span = tracy_client::span!("ResolvedWindowRules::compute");
+
+        let mut resolved = ResolvedWindowRules::empty();
+
+        let toplevel = window.toplevel();
+        with_states(toplevel.wl_surface(), |states| {
+            let mut role = states
+                .data_map
+                .get::<XdgToplevelSurfaceData>()
+                .unwrap()
+                .lock()
+                .unwrap();
+
+            // Ensure server_pending like in Smithay's with_pending_state().
+            if role.server_pending.is_none() {
+                role.server_pending = Some(role.current_server_state().clone());
+            }
+
+            let mut open_on_output = None;
+
+            for rule in rules {
+                let matches = |m| window_matches(window, &role, m);
+
+                if !(rule.matches.is_empty() || rule.matches.iter().any(matches)) {
+                    continue;
+                }
+
+                if rule.excludes.iter().any(matches) {
+                    continue;
+                }
+
+                if let Some(x) = rule
+                    .default_column_width
+                    .as_ref()
+                    .map(|d| d.0.map(ColumnWidth::from))
+                {
+                    resolved.default_width = Some(x);
+                }
+
+                if let Some(x) = rule.open_on_output.as_deref() {
+                    open_on_output = Some(x);
+                }
+
+                if let Some(x) = rule.open_maximized {
+                    resolved.open_maximized = Some(x);
+                }
+
+                if let Some(x) = rule.open_fullscreen {
+                    resolved.open_fullscreen = Some(x);
+                }
+
+                if let Some(x) = rule.min_width {
+                    resolved.min_width = Some(x);
+                }
+                if let Some(x) = rule.min_height {
+                    resolved.min_height = Some(x);
+                }
+                if let Some(x) = rule.max_width {
+                    resolved.max_width = Some(x);
+                }
+                if let Some(x) = rule.max_height {
+                    resolved.max_height = Some(x);
+                }
+
+                if let Some(x) = rule.draw_border_with_background {
+                    resolved.draw_border_with_background = Some(x);
+                }
+                if let Some(x) = rule.opacity {
+                    resolved.opacity = Some(x);
+                }
+                if let Some(x) = rule.block_out_from {
+                    resolved.block_out_from = Some(x);
+                }
+            }
+
+            resolved.open_on_output = open_on_output.map(|x| x.to_owned());
+        });
+
+        resolved
+    }
+}
+
+fn window_matches(window: WindowRef, role: &XdgToplevelSurfaceRoleAttributes, m: &Match) -> bool {
+    // Must be ensured by the caller.
+    let server_pending = role.server_pending.as_ref().unwrap();
+
+    if let Some(is_focused) = m.is_focused {
+        if window.is_focused() != is_focused {
+            return false;
+        }
+    }
+
+    if let Some(is_active) = m.is_active {
+        // Our "is-active" definition corresponds to the window having a pending Activated state.
+        let pending_activated = server_pending
+            .states
+            .contains(xdg_toplevel::State::Activated);
+        if is_active != pending_activated {
+            return false;
+        }
+    }
+
+    if let Some(app_id_re) = &m.app_id {
+        let Some(app_id) = &role.app_id else {
+            return false;
+        };
+        if !app_id_re.is_match(app_id) {
+            return false;
+        }
+    }
+
+    if let Some(title_re) = &m.title {
+        let Some(title) = &role.title else {
+            return false;
+        };
+        if !title_re.is_match(title) {
+            return false;
+        }
+    }
+
+    true
+}

src/window/unmapped.rs

@@ -0,0 +1,66 @@
+use smithay::desktop::Window;
+use smithay::output::Output;
+use smithay::wayland::shell::xdg::ToplevelSurface;
+
+use super::ResolvedWindowRules;
+use crate::layout::workspace::ColumnWidth;
+
+#[derive(Debug)]
+pub struct Unmapped {
+    pub window: Window,
+    pub state: InitialConfigureState,
+}
+
+#[derive(Debug)]
+pub enum InitialConfigureState {
+    /// The window has not been initially configured yet.
+    NotConfigured {
+        /// Whether the window requested to be fullscreened, and the requested output, if any.
+        wants_fullscreen: Option<Option<Output>>,
+    },
+    /// The window has been configured.
+    Configured {
+        /// Up-to-date rules.
+        ///
+        /// We start tracking window rules when sending the initial configure, since they don't
+        /// affect anything before that.
+        rules: ResolvedWindowRules,
+
+        /// Resolved default width for this window.
+        ///
+        /// `None` means that the window will pick its own width.
+        width: Option<ColumnWidth>,
+
+        /// Whether the window should open full-width.
+        is_full_width: bool,
+
+        /// Output to open this window on.
+        ///
+        /// This can be `None` in cases like:
+        ///
+        /// - There are no outputs connected.
+        /// - This is a dialog with a parent, and there was no explicit output set, so this dialog
+        ///   should fetch the parent's current output again upon mapping.
+        output: Option<Output>,
+    },
+}
+
+impl Unmapped {
+    /// Wraps a newly created window that hasn't been initially configured yet.
+    pub fn new(window: Window) -> Self {
+        Self {
+            window,
+            state: InitialConfigureState::NotConfigured {
+                wants_fullscreen: None,
+            },
+        }
+    }
+
+    pub fn needs_initial_configure(&self) -> bool {
+        matches!(self.state, InitialConfigureState::NotConfigured { .. })
+    }
+
+    pub fn toplevel(&self) -> &ToplevelSurface {
+        self.window.toplevel().expect("no X11 support")
+    }
+}

wiki/Application-Issues.md

@@ -0,0 +1,30 @@
+### VSCode
+
+There seems to be a bug in VSCode's Wayland backend until 1.86.0 which causes the window to not show up when using server-side decorations. So, to run VSCode:
+
+1. Make sure VSCode is 1.86.0 or above, or that `prefer-no-csd` is **not set** in the niri config
+2. Run `code --ozone-platform-hint=auto --enable-features=WaylandWindowDecorations`
+
+Also, if you're having issues with some VSCode hotkeys, try starting `Xwayland` and setting the `DISPLAY=:0` environment variable for VSCode. That is, still running VSCode with the Wayland backend, but with `DISPLAY` set to a running Xwayland instance. Apparently, VSCode currently unconditionally queries the X server for a keymap.
+
+### Chromium
+
+When creating new windows within Chromium (e.g. with <kbd>Ctrl</kbd><kbd>N</kbd>), there's a Chromium bug with sizing:
+
+- With CSD (`prefer-no-csd` unset), the window will be a bit smaller than needed
+- With SSD (`prefer-no-csd` set), the window buffer will be offset to the top-left
+
+Both of these can be fixed by resizing the new Chromium window.
+
+### WezTerm
+
+There's [a bug](https://github.com/wez/wezterm/issues/4708) in WezTerm that it waits for a zero-sized Wayland configure event, so its window never shows up in niri. To work around it, put this window rule in the niri config (included in the default config):
+
+```
+window-rule {
+    match app-id=r#"^org\.wezfurlong\.wezterm$"#
+    default-column-width {}
+}
+```
+
+This empty default column width lets WezTerm pick its own initial width which makes it show up properly.

wiki/Configuration:-Animations.md

@@ -0,0 +1,258 @@
+### Overview
+
+Niri has several animations which you can configure in the same way.
+Additionally, you can disable or slow down all animations at once.
+
+Here's a quick glance at the available animations with their default values.
+
+```
+animations {
+    // Uncomment to turn off all animations.
+    // You can also put "off" into each individual animation to disable it.
+    // off
+
+    // Slow down all animations by this factor. Values below 1 speed them up instead.
+    // slowdown 3.0
+
+    // Individual animations.
+
+    workspace-switch {
+        spring damping-ratio=1.0 stiffness=1000 epsilon=0.0001
+    }
+
+    window-open {
+        duration-ms 150
+        curve "ease-out-expo"
+    }
+
+    window-close {
+        duration-ms 150
+        curve "ease-out-quad"
+    }
+
+    horizontal-view-movement {
+        spring damping-ratio=1.0 stiffness=800 epsilon=0.0001
+    }
+
+    window-movement {
+        spring damping-ratio=1.0 stiffness=800 epsilon=0.0001
+    }
+
+    window-resize {
+        spring damping-ratio=1.0 stiffness=800 epsilon=0.0001
+    }
+
+    config-notification-open-close {
+        spring damping-ratio=0.6 stiffness=1000 epsilon=0.001
+    }
+}
+```
+
+### Animation Types
+
+There are two animation types: easing and spring.
+Each animation can be either an easing or a spring.
+
+#### Easing
+
+This is a relatively common animation type that changes the value over a set duration using an interpolation curve.
+
+To use this animation, set the following parameters:
+
+- `duration-ms`: duration of the animation in milliseconds.
+- `curve`: the easing curve to use.
+
+```
+animations {
+    window-open {
+        duration-ms 150
+        curve "ease-out-expo"
+    }
+}
+```
+
+Currently, niri only supports three curves:
+
+- `ease-out-quad` <sup>Since: 0.1.5</sup>
+- `ease-out-cubic`
+- `ease-out-expo`
+
+You can get a feel for them on pages like [easings.net](https://easings.net/).
+
+#### Spring
+
+Spring animations use a model of a physical spring to animate the value.
+They notably feel better with touchpad gestures, because they take into account the velocity of your fingers as you release the swipe.
+Springs can also oscillate / bounce at the end with the right parameters if you like that sort of thing, but they don't have to (and by default they mostly don't).
+
+Due to springs using a physical model, the animation parameters are less obvious and generally should be tuned with trial and error.
+Notably, you cannot directly set the duration.
+You can use the [Elastic](https://flathub.org/apps/app.drey.Elastic) app to help visualize how the spring parameters change the animation.
+
+A spring animation is configured like this, with three mandatory parameters:
+
+```
+animations {
+    workspace-switch {
+        spring damping-ratio=1.0 stiffness=1000 epsilon=0.0001
+    }
+}
+```
+
+The `damping-ratio` goes from 0.1 to 10.0 and has the following properties:
+
+- below 1.0: underdamped spring, will oscillate in the end.
+- above 1.0: overdamped spring, won't oscillate.
+- 1.0: critically damped spring, comes to rest in minimum possible time without oscillations.
+
+However, even with damping ratio = 1.0, the spring animation may oscillate if "launched" with enough velocity from a touchpad swipe.
+
+> [!WARNING]
+> Overdamped springs currently have some numerical stability issues and may cause graphical glitches.
+> Therefore, setting `damping-ratio` above `1.0` is not recommended.
+
+Lower `stiffness` will result in a slower animation more prone to oscillation.
+
+Set `epsilon` to a lower value if the animation "jumps" at the end.
+
+> [!TIP]
+> The spring *mass* (which you can see in Elastic) is hardcoded to 1.0 and cannot be changed.
+> Instead, change `stiffness` proportionally.
+> E.g. increasing mass by 2× is the same as decreasing stiffness by 2×.
+
+### Animations
+
+Now let's go into more detail on the animations that you can configure.
+
+#### `workspace-switch`
+
+Animation when switching workspaces up and down, including after the vertical touchpad gesture (a spring is recommended).
+
+```
+animations {
+    workspace-switch {
+        spring damping-ratio=1.0 stiffness=1000 epsilon=0.0001
+    }
+}
+```
+
+#### `window-open`
+
+Window opening animation.
+
+This one uses an easing type by default.
+
+```
+animations {
+    window-open {
+        duration-ms 150
+        curve "ease-out-expo"
+    }
+}
+```
+
+#### `window-close`
+
+<sup>Since: 0.1.5</sup>
+
+Window closing animation.
+
+This one uses an easing type by default.
+
+```
+animations {
+    window-open {
+        duration-ms 150
+        curve "ease-out-quad"
+    }
+}
+```
+
+#### `horizontal-view-movement`
+
+All horizontal camera view movement animations, such as:
+
+- When a window off-screen is focused and the camera scrolls to it.
+- When a new window appears off-screen and the camera scrolls to it.
+- After a horizontal touchpad gesture (a spring is recommended).
+
+```
+animations {
+    horizontal-view-movement {
+        spring damping-ratio=1.0 stiffness=800 epsilon=0.0001
+    }
+}
+```
+
+#### `window-movement`
+
+<sup>Since: 0.1.5</sup>
+
+Movement of individual windows within a workspace.
+
+Includes:
+
+- Moving window columns with `move-column-left` and `move-column-right`.
+- Moving windows inside a column with `move-window-up` and `move-window-down`.
+- Moving windows out of the way upon window opening and closing.
+- Window movement between columns when consuming/expelling.
+
+This animation *does not* include the camera view movement, such as scrolling the workspace left and right.
+
+```
+animations {
+    window-movement {
+        spring damping-ratio=1.0 stiffness=800 epsilon=0.0001
+    }
+}
+```
+
+#### `window-resize`
+
+<sup>Since: 0.1.5</sup>
+
+Window resize animation.
+
+Only manual window resizes are animated, i.e. when you resize the window with `switch-preset-column-width` or `maximize-column`.
+Also, very small resizes (up to 10 pixels) are not animated.
+
+```
+animations {
+    window-resize {
+        spring damping-ratio=1.0 stiffness=800 epsilon=0.0001
+    }
+}
+```
+
+#### `config-notification-open-close`
+
+The open/close animation of the config parse error and new default config notifications.
+
+This one uses an underdamped spring by default (`damping-ratio=0.6`) which causes a slight oscillation in the end.
+
+```
+animations {
+    config-notification-open-close {
+        spring damping-ratio=0.6 stiffness=1000 epsilon=0.001
+    }
+}
+```
+
+### Synchronized Animations
+
+<sup>Since: 0.1.5</sup>
+
+Sometimes, when two animations are meant to play together synchronized, niri will drive them both with the same configuration.
+
+For example, if a window resize causes the view to move, then that view movement animation will also use the `window-resize` configuration (rather than the `horizontal-view-movement` configuration).
+This is especially important for animated resizes to look good when using `center-focused-column "always"`.
+
+As another example, resizing a window in a column vertically causes other windows to move up or down into their new position.
+This movement will use the `window-resize` configuration, rather than the `window-movement` configuration, to keep the animations synchronized.
+
+A few actions are still missing this synchronization logic, since in some cases it is difficult to implement properly.
+Therefore, for the best results, consider using the same parameters for related animations (they are all the same by default):
+
+- `horizontal-view-movement`
+- `window-movement`
+- `window-resize`

wiki/Configuration:-Debug-Options.md

@@ -0,0 +1,140 @@
+### Overview
+
+Niri has several options that are only useful for debugging, or are experimental and have known issues.
+They are not meant for normal use.
+
+> [!CAUTION]
+> These options are **not** covered by the [config breaking change policy](./Configuration:-Overview.md).
+> They can change or stop working at any point with little notice.
+
+Here are all the options at a glance:
+
+```
+debug {
+    preview-render "screencast"
+    // preview-render "screen-capture"
+    enable-overlay-planes
+    disable-cursor-plane
+    render-drm-device "/dev/dri/renderD129"
+    dbus-interfaces-in-non-session-instances
+    wait-for-frame-completion-before-queueing
+    emulate-zero-presentation-time
+    enable-color-transformations-capability
+}
+```
+
+### `preview-render`
+
+Make niri render the monitors the same way as for a screencast or a screen capture.
+
+Useful for previewing the `block-out-from` window rule.
+
+```
+debug {
+    preview-render "screencast"
+    // preview-render "screen-capture"
+}
+```
+
+### `enable-overlay-planes`
+
+Enable direct scanout into overlay planes.
+May cause frame drops during some animations on some hardware (which is why it is not the default).
+
+Direct scanout into the primary plane is always enabled.
+
+```
+debug {
+    enable-overlay-planes
+}
+```
+
+### `disable-cursor-plane`
+
+Disable the use of the cursor plane.
+The cursor will be rendered together with the rest of the frame.
+
+Useful to work around driver bugs on specific hardware.
+
+```
+debug {
+    disable-cursor-plane
+}
+```
+
+### `render-drm-device`
+
+Override the DRM device that niri will use for all rendering.
+
+You can set this to make niri use a different primary GPU than the default one.
+
+```
+debug {
+    render-drm-device "/dev/dri/renderD129"
+}
+```
+
+### `dbus-interfaces-in-non-session-instances`
+
+Make niri create its D-Bus interfaces even if it's not running as a `--session`.
+
+Useful for testing screencasting changes without having to relogin.
+
+The main niri instance will *not* currently take back the interfaces when you close the test instance, so you will need to relogin in the end to make screencasting work again.
+
+```
+debug {
+    dbus-interfaces-in-non-session-instances
+}
+```
+
+### `wait-for-frame-completion-before-queueing`
+
+Wait until every frame is done rendering before handing it over to DRM.
+
+Useful for diagnosing certain synchronization and performance problems.
+
+```
+debug {
+    wait-for-frame-completion-before-queueing
+}
+```
+
+### `emulate-zero-presentation-time`
+
+Emulate zero (unknown) presentation time returned from DRM.
+
+This is a thing on NVIDIA proprietary drivers, so this flag can be used to test that niri doesn't break too hard on those systems.
+
+```
+debug {
+    emulate-zero-presentation-time
+}
+```
+
+### `enable-color-transformations-capability`
+
+Enable the color-transformations capability of the Smithay renderer.
+May cause a slight decrease in rendering performance.
+
+Currently, should cause no visible changes in behavior, but it will be needed for HDR support whenever that happens.
+So, this flag exists to be able to make sure that nothing breaks.
+
+```
+debug {
+    enable-color-transformations-capability
+}
+```
+
+### `toggle-debug-tint` Key Binding
+
+This one is not a debug option, but rather a key binding.
+
+It will tint all surfaces green, unless they are being directly scanned out.
+It's therefore useful to check if direct scanout is working.
+
+```
+binds {
+    Mod+Shift+Ctrl+T { toggle-debug-tint; }
+}
+```

wiki/Configuration:-Input.md

@@ -0,0 +1,197 @@
+### Overview
+
+In this section you can configure input devices like keyboard and mouse, and some input-related options.
+
+There's a section for each device type: `keyboard`, `touchpad`, `mouse`, `trackpoint`, `tablet`, `touch`.
+Settings in those sections will apply to every device of that type.
+Currently, there's no way to configure specific devices individually (but that is planned).
+
+All settings at a glance:
+
+```
+input {
+    keyboard {
+        xkb {
+            // layout "us"
+            // variant "colemak_dh_ortho"
+            // options "compose:ralt,ctrl:nocaps"
+            // model ""
+            // rules ""
+        }
+
+        // repeat-delay 600
+        // repeat-rate 25
+        // track-layout "global"
+    }
+
+    touchpad {
+        tap
+        // dwt
+        // dwtp
+        natural-scroll
+        // accel-speed 0.2
+        // accel-profile "flat"
+        // tap-button-map "left-middle-right"
+        // click-method "clickfinger"
+    }
+
+    mouse {
+        // natural-scroll
+        // accel-speed 0.2
+        // accel-profile "flat"
+    }
+
+    trackpoint {
+        // natural-scroll
+        // accel-speed 0.2
+        // accel-profile "flat"
+    }
+
+    tablet {
+        map-to-output "eDP-1"
+    }
+
+    touch {
+        map-to-output "eDP-1"
+    }
+
+    // disable-power-key-handling
+    // warp-mouse-to-focus
+    // focus-follows-mouse
+    // workspace-auto-back-and-forth
+}
+```
+
+### Keyboard
+
+#### Layout
+
+In the `xkb` section, you can set layout, variant, options, model and rules.
+These are passed directly to libxkbcommon, which is also used by most other Wayland compositors.
+See the `xkeyboard-config(7)` manual for more information.
+
+```
+input {
+    keyboard {
+        xkb {
+            layout "us"
+            variant "colemak_dh_ortho"
+            options "compose:ralt,ctrl:nocaps"
+        }
+    }
+}
+```
+
+When using multiple layouts, niri can remember the current layout globally (the default) or per-window.
+You can control this with the `track-layout` option.
+
+- `global`: layout change is global for all windows.
+- `window`: layout is tracked for each window individually.
+
+```
+input {
+    keyboard {
+        track-layout "global"
+    }
+}
+```
+
+#### Repeat
+
+Delay is in milliseconds before the keyboard repeat starts.
+Rate is in characters per second.
+
+```
+input {
+    keyboard {
+        repeat-delay 600
+        repeat-rate 25
+    }
+}
+```
+
+### Pointing Devices
+
+Most settings for the pointing devices are passed directly to libinput.
+Other Wayland compositors also use libinput, so it's likely you will find the same settings there.
+For flags like `tap`, omit them or comment them out to disable the setting.
+
+A few settings are common between `touchpad`, `mouse` and `trackpoint`:
+
+- `natural-scroll`: if set, inverts the scrolling direction.
+- `accel-speed`: pointer acceleration speed, valid values are from `-1.0` to `1.0` where the default is `0.0`.
+- `accel-profile`: can be `adaptive` (the default) or `flat` (disables pointer acceleration).
+
+Settings specific to `touchpad`s:
+
+- `tap`: tap-to-click.
+- `dwt`: disable-when-typing.
+- `dwtp`: disable-when-trackpointing.
+- `tap-button-map`: can be `left-right-middle` or `left-middle-right`, controls which button corresponds to a two-finger tap and a three-finger tap.
+- `click-method`: can be `button-areas` or `clickfinger`, changes the [click method](https://wayland.freedesktop.org/libinput/doc/latest/clickpad-softbuttons.html).
+
+Tablets and touchscreens are absolute pointing devices that can be mapped to a specific output like so:
+
+```
+input {
+    tablet {
+        map-to-output "eDP-1"
+    }
+
+    touch {
+        map-to-output "eDP-1"
+    }
+}
+```
+
+Valid output names are the same as the ones used for output configuration.
+
+### General Settings
+
+These settings are not specific to a particular input device.
+
+#### `disable-power-key-handling`
+
+By default, niri will take over the power button to make it sleep instead of power off.
+Set this if you would like to configure the power button elsewhere (i.e. `logind.conf`).
+
+```
+input {
+    disable-power-key-handling
+}
+```
+
+#### `warp-mouse-to-focus`
+
+Makes the mouse warp to newly focused windows.
+
+X and Y coordinates are computed separately, i.e. if moving the mouse only horizontally is enough to put it inside the newly focused window, then it will move only horizontally.
+
+```
+input {
+    warp-mouse-to-focus
+}
+```
+
+#### `focus-follows-mouse`
+
+Focuses windows and outputs automatically when moving the mouse over them.
+
+```
+input {
+    focus-follows-mouse
+}
+```
+
+#### `workspace-auto-back-and-forth`
+
+Normally, switching to the same workspace by index twice will do nothing (since you're already on that workspace).
+If this flag is enabled, switching to the same workspace by index twice will switch back to the previous workspace.
+
+Niri will correctly switch to the workspace you came from, even if workspaces were reordered in the meantime.
+
+```
+input {
+    workspace-auto-back-and-forth
+}
+```