chore: reduce component overhead (#3)

Reviewed-on: #3

crates/utils/src/lib.rs

@@ -1,7 +1,8 @@
 use gpui::prelude::FluentBuilder as _;
 use gpui::{
     App, Bounds, BoxShadow, Div, ElementId, FocusHandle, Global, Hsla, IntoElement, Pixels,
-    Refineable as _, StatefulInteractiveElement, StyleRefinement, Styled, Window, div, px,
+    Refineable as _, StatefulInteractiveElement, StyleRefinement, Styled, Window, WindowId, div,
+    px,
 };
 use gpui_native_theme::ActiveTheme as _;
 use std::collections::HashMap;
@@ -36,39 +37,36 @@ pub fn focus_handle(id: &ElementId, window: &mut Window, cx: &mut App) -> FocusH
         .clone()
 }
 
-/// The painted bounds of elements that tooltips anchor to, keyed by element id.
-#[derive(Clone, Default)]
-struct AnchorBoundsRegistry(HashMap<ElementId, Bounds<Pixels>>);
+/// The painted bounds of elements that tooltips anchor to, per window and element id.
+#[derive(Default)]
+struct AnchorBoundsRegistry(HashMap<(WindowId, ElementId), Bounds<Pixels>>);
 
 impl Global for AnchorBoundsRegistry {}
 
 impl AnchorBoundsRegistry {
-    fn record(&mut self, id: ElementId, bounds: Bounds<Pixels>) {
-        self.0.insert(id, bounds);
+    fn record(&mut self, window: WindowId, id: ElementId, bounds: Bounds<Pixels>) {
+        self.0.insert((window, id), bounds);
     }
 
-    fn get(&self, id: &ElementId) -> Option<Bounds<Pixels>> {
-        self.0.get(id).copied()
+    fn get(&self, window: WindowId, id: &ElementId) -> Option<Bounds<Pixels>> {
+        self.0.get(&(window, id.clone())).copied()
     }
 }
 
-/// The last bounds an element painted at.
-pub fn anchor_bounds(id: &ElementId, cx: &mut App) -> Option<Bounds<Pixels>> {
+/// The last bounds an element painted at, in the given window.
+pub fn anchor_bounds(window: WindowId, id: &ElementId, cx: &App) -> Option<Bounds<Pixels>> {
     cx.try_global::<AnchorBoundsRegistry>()
-        .and_then(|registry| registry.get(id))
+        .and_then(|registry| registry.get(window, id))
 }
 
 /// A canvas prepaint closure recording the element's painted bounds.
 pub fn record_anchor_bounds(
     id: ElementId,
 ) -> impl Fn(Bounds<Pixels>, &mut Window, &mut App) + 'static {
-    move |bounds, _window, cx| {
-        let mut registry = cx
-            .try_global::<AnchorBoundsRegistry>()
-            .cloned()
-            .unwrap_or_default();
-        registry.record(id.clone(), bounds);
-        cx.set_global(registry);
+    move |bounds, window, cx| {
+        let window_id = window.window_handle().window_id();
+        cx.default_global::<AnchorBoundsRegistry>()
+            .record(window_id, id.clone(), bounds);
     }
 }