Keep font wheel events with their overlay target

crates/ui-egui/src/font_menu.rs

@@ -452,6 +452,13 @@ struct QueuedWheel {
     positions_after: Vec<egui::Pos2>,
 }
 
+#[derive(Clone)]
+struct ReplayWheel {
+    target: egui::LayerId,
+    position: egui::Pos2,
+    event: egui::Event,
+}
+
 #[derive(Clone, Default)]
 struct WheelFields {
     pass: u64,
@@ -462,7 +469,7 @@ struct WheelFields {
     fields: Vec<WheelField>,
     pending: HashMap<egui::Id, Vec<WheelInput>>,
     queued: Vec<QueuedWheel>,
-    replay: Vec<egui::Event>,
+    replay: Vec<ReplayWheel>,
 }
 
 #[cfg(not(target_arch = "wasm32"))]
@@ -505,8 +512,9 @@ impl egui::Plugin for WheelLayerSnapshot {
             let id = event.field.with("wheel");
             if !active {
                 ctx.data_mut(|d| d.remove::<f32>(id));
-                fields.replay.push(egui::Event::PointerMoved(event.position));
-                fields.replay.push(event.event);
+                if let Some(target) = ctx.layer_id_at(event.position) {
+                    fields.replay.push(ReplayWheel { target, position: event.position, event: event.event });
+                }
             } else {
                 let notches = ctx.data(|d| d.get_temp::<f32>(id)).unwrap_or(0.0) + event.amount;
                 let whole = notches.trunc();
@@ -521,7 +529,6 @@ impl egui::Plugin for WheelLayerSnapshot {
             }
         }
         if fields.replay.len() > replayed {
-            fields.replay.push(fields.pointer.map_or(egui::Event::PointerGone, egui::Event::PointerMoved));
             ctx.request_repaint();
         }
         ctx.data_mut(|d| d.insert_temp(key, fields));
@@ -796,7 +803,21 @@ pub(crate) fn take_raw_wheel(ctx: &egui::Context, raw: &mut egui::RawInput) {
         true
     });
     if !fields.replay.is_empty() {
-        raw.events.splice(0..0, std::mem::take(&mut fields.replay));
+        let mut replay = Vec::new();
+        for wheel in std::mem::take(&mut fields.replay) {
+            #[cfg(not(target_arch = "wasm32"))]
+            let target_still_visible = native_layers.as_ref().is_some_and(|layers| (layers.0)(wheel.position) == Some(wheel.target));
+            #[cfg(target_arch = "wasm32")]
+            let target_still_visible = false;
+            if target_still_visible {
+                replay.push(egui::Event::PointerMoved(wheel.position));
+                replay.push(wheel.event);
+            }
+        }
+        if !replay.is_empty() {
+            replay.push(pointer.map_or(egui::Event::PointerGone, egui::Event::PointerMoved));
+            raw.events.splice(0..0, replay);
+        }
     }
     fields.pointer = pointer;
     ctx.data_mut(|d| d.insert_temp(key, fields));

crates/ui-egui/src/panel_docking/native_tests.rs

@@ -785,6 +785,49 @@ fn an_overlay_raised_with_the_wheel_event_does_not_change_the_font() {
     assert_eq!(h.app.run("text.fonts", json!({})).unwrap(), before);
 }
 
+#[test]
+fn a_closed_overlay_does_not_replay_its_wheel_into_the_panel() {
+    let mut h = Harness::new();
+    h.app.run("text.create", json!({"x": 30, "y": 50, "text": "Hi", "font": "Source Sans 3"})).unwrap();
+    let viewport = h.float("character");
+    let field = h
+        .host
+        .borrow()
+        .windows
+        .get(&viewport)
+        .and_then(|w| w.texts.iter().find(|(text, _)| text == "Source Sans 3").map(|(_, rect)| *rect))
+        .expect("the Character panel's font family field");
+    let pointer = pos2(field.min.x + 4.0, field.center().y);
+    h.host.borrow_mut().child_raise_overlay = Some((viewport, field.expand(10.0), false));
+    h.frames(2);
+    let field_layer = crate::font_menu::wheel_field_layer_for_test(&h.ctx, viewport, pointer).expect("the font field layer");
+    h.host.borrow_mut().child_raise_layer = Some((viewport, field_layer));
+    h.frame(vec![]);
+    h.host.borrow_mut().child_raise_layer = None;
+    h.frame(vec![]);
+    let before = h.app.run("text.fonts", json!({})).unwrap();
+    h.host.borrow_mut().child_raise_overlay = Some((viewport, field.expand(10.0), true));
+    h.host.borrow_mut().windows.get_mut(&viewport).unwrap().events.extend([
+        Event::PointerMoved(pointer),
+        Event::MouseWheel {
+            unit: egui::MouseWheelUnit::Line,
+            delta: vec2(0.0, -1.0),
+            phase: egui::TouchPhase::Move,
+            modifiers: Default::default(),
+            source: egui::MouseWheelSource::Unknown,
+        },
+    ]);
+    h.frame(vec![]);
+    h.host.borrow_mut().child_raise_overlay = None;
+    h.frame(vec![]);
+    h.frame(vec![]);
+    assert!(
+        !h.ctx.input_for(viewport, |input| input.raw.events.iter().any(|event| matches!(event, Event::MouseWheel { .. }))),
+        "a closed overlay cannot receive a later wheel event"
+    );
+    assert_eq!(h.app.run("text.fonts", json!({})).unwrap(), before);
+}
+
 #[test]
 fn wheel_events_on_both_sides_of_an_overlay_are_checked_separately() {
     let mut h = Harness::new();