Refactor: move some state

crates/egui/src/containers/popup.rs

@@ -125,9 +125,10 @@ fn show_tooltip_at_dyn<'c, R>(
 
     let mut state = ctx.frame_state_mut(|fs| {
         // Remember that this is the widget showing the tooltip:
-        fs.tooltips
-            .per_layer_tooltip_widget
-            .insert(parent_layer, widget_id);
+        fs.layers
+            .entry(parent_layer)
+            .or_default()
+            .widget_with_tooltip = Some(widget_id);
 
         fs.tooltips
             .widget_tooltips

crates/egui/src/frame_state.rs

@@ -8,22 +8,12 @@ pub struct TooltipFrameState {
     /// If a tooltip has been shown this frame, where was it?
     /// This is used to prevent multiple tooltips to cover each other.
     pub widget_tooltips: IdMap<PerWidgetTooltipState>,
-
-    /// For each layer, which widget is showing a tooltip (if any)?
-    ///
-    /// Only one widget per layer may show a tooltip.
-    /// But if a tooltip contains a tooltip, you can show a tooltip on top of a tooltip.
-    pub per_layer_tooltip_widget: ahash::HashMap<LayerId, Id>,
 }
 
 impl TooltipFrameState {
     pub fn clear(&mut self) {
-        let Self {
-            widget_tooltips,
-            per_layer_tooltip_widget,
-        } = self;
+        let Self { widget_tooltips } = self;
         widget_tooltips.clear();
-        per_layer_tooltip_widget.clear();
     }
 }
 
@@ -42,6 +32,12 @@ pub struct PerLayerState {
     ///
     /// Does NOT include tooltips.
     pub open_popups: HashSet<Id>,
+
+    /// Which widget is showing a tooltip (if any)?
+    ///
+    /// Only one widget per layer may show a tooltip.
+    /// But if a tooltip contains a tooltip, you can show a tooltip on top of a tooltip.
+    pub widget_with_tooltip: Option<Id>,
 }
 
 #[cfg(feature = "accesskit")]

crates/egui/src/response.rs

@@ -656,10 +656,12 @@ impl Response {
         }
 
         let is_other_tooltip_open = self.ctx.prev_frame_state(|fs| {
-            if let Some(already_open_tooltip) =
-                fs.tooltips.per_layer_tooltip_widget.get(&self.layer_id)
+            if let Some(already_open_tooltip) = fs
+                .layers
+                .get(&self.layer_id)
+                .and_then(|layer| layer.widget_with_tooltip)
             {
-                already_open_tooltip != &self.id
+                already_open_tooltip != self.id
             } else {
                 false
             }