Add open-maximized window rule

niri-config/src/lib.rs

@@ -583,6 +583,8 @@ pub struct WindowRule {
     pub default_column_width: Option<DefaultColumnWidth>,
     #[knuffel(child, unwrap(argument))]
     pub open_on_output: Option<String>,
+    #[knuffel(child, unwrap(argument))]
+    pub open_maximized: Option<bool>,
 }
 
 #[derive(knuffel::Decode, Debug, Default, Clone)]
@@ -1062,6 +1064,7 @@ mod tests {
                 exclude title="~"
 
                 open-on-output "eDP-1"
+                open-maximized true
             }
 
             binds {
@@ -1221,6 +1224,7 @@ mod tests {
                         title: Some(Regex::new("~").unwrap()),
                     }],
                     open_on_output: Some("eDP-1".to_owned()),
+                    open_maximized: Some(true),
                     ..Default::default()
                 }],
                 binds: Binds(vec![

resources/default-config.kdl

@@ -305,6 +305,9 @@ animations {
     // If such an output does not exist, it will open on the currently
     // focused output as usual.
     open-on-output "eDP-1"
+
+    // Make this window open as a maximized column.
+    open-maximized true
 }
 
 // Here's a useful example. Work around WezTerm's initial configure bug

src/handlers/compositor.rs

@@ -109,16 +109,22 @@ impl CompositorHandler for State {
 
                     window.on_commit();
 
-                    let (width, output) =
+                    let (width, is_full_width, output) =
-                        if let InitialConfigureState::Configured { width, output, .. } = state {
+                        if let InitialConfigureState::Configured {
+                            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());
 
-                            (width, output)
+                            (width, is_full_width, output)
                         } else {
                             error!("window map must happen after initial configure");
-                            (None, None)
+                            (None, false, None)
                         };
 
                     let parent = window
@@ -140,14 +146,16 @@ impl CompositorHandler for State {
 
                     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, win, width, false)
+                        self.niri
+                            .layout
+                            .add_window_right_of(&p, win, width, is_full_width)
                     } else if let Some(output) = &output {
                         self.niri
                             .layout
-                            .add_window_on_output(output, win, width, false);
+                            .add_window_on_output(output, win, width, is_full_width);
                         Some(output)
                     } else {
-                        self.niri.layout.add_window(win, width, false)
+                        self.niri.layout.add_window(win, width, is_full_width)
                     };
 
                     if let Some(output) = output.cloned() {

src/handlers/xdg_shell.rs

@@ -89,6 +89,10 @@ pub fn resolve_window_rules(
             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);
+            }
         }
 
         resolved.open_on_output = open_on_output.map(|x| x.to_owned());
@@ -503,6 +507,7 @@ impl State {
         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
@@ -518,7 +523,13 @@ impl State {
             }
 
             width = ws.resolve_default_width(rules.default_width);
-            ws.configure_new_window(window, 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
@@ -536,6 +547,7 @@ impl State {
         *state = InitialConfigureState::Configured {
             rules,
             width,
+            is_full_width,
             output,
         };
 

src/window.rs

@@ -29,6 +29,9 @@ pub enum InitialConfigureState {
         /// `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:
@@ -52,6 +55,9 @@ pub struct ResolvedWindowRules {
 
     /// Output to open this window on.
     pub open_on_output: Option<String>,
+
+    /// Whether the window should open full-width.
+    pub open_maximized: Option<bool>,
 }
 
 impl Unmapped {