Implement focus-follows-mouse

2 files changed, 27 insertions, 0 deletions

diff --git a/src/input.rs b/src/input.rs
index c7a0e264..1d99f550 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -903,6 +903,8 @@ impl State {
             }
         }
 
+        self.niri.handle_focus_follows_mouse(&under);
+
         // Activate a new confinement if necessary.
         self.niri.maybe_activate_pointer_constraint(new_pos, &under);
 
@@ -967,6 +969,9 @@ impl State {
         }
 
         let under = self.niri.surface_under_and_global_space(pos);
+
+        self.niri.handle_focus_follows_mouse(&under);
+
         self.niri.maybe_activate_pointer_constraint(pos, &under);
         self.niri.pointer_focus.clone_from(&under);
 
diff --git a/src/niri.rs b/src/niri.rs
index ef369e35..f63f05a3 100644
--- a/src/niri.rs
+++ b/src/niri.rs
@@ -3305,6 +3305,28 @@ impl Niri {
             warn!("error spawning a thread to send MonitorsChanged: {err:?}");
         }
     }
+
+    pub fn handle_focus_follows_mouse(&mut self, new_focus: &PointerFocus) {
+        if !self.config.borrow().input.focus_follows_mouse {
+            return;
+        }
+
+        if self.seat.get_pointer().unwrap().is_grabbed() {
+            return;
+        }
+
+        if let Some(output) = &new_focus.output {
+            if self.pointer_focus.output.as_ref() != Some(output) {
+                self.layout.focus_output(output);
+            }
+        }
+
+        if let Some(window) = &new_focus.window {
+            if self.pointer_focus.window.as_ref() != Some(window) {
+                self.layout.activate_window(window);
+            }
+        }
+    }
 }
 
 pub struct ClientState {