perf: cache entity views to skip layout recomputation on non-dirty frames

GPUI rebuilds and re-lays-out the entire taffy tree on every frame,
even for views that haven't changed. Use AnyView::cached(style) on
Entity children so non-dirty views are represented as a single taffy
leaf node and their previous layout+paint is reused from the prior frame.

Cached views: SimpleRoot→RootView, RootView→Sidebar/ProjectColumn,
ProjectColumn→LayoutContainer, LayoutContainer→TerminalPane/children,
TerminalPane→TerminalContent, DetachedTerminal→TerminalContent.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: matej21

crates/okena-views-terminal/src/layout/layout_container.rs

@@ -246,7 +246,9 @@ impl<D: ActionDispatch + Send + Sync> LayoutContainer<D> {
                     .flex_1()
                     .min_h_0()
                     .relative()
-                    .child(self.terminal_pane.clone().unwrap())
+                    .child(AnyView::from(self.terminal_pane.clone().unwrap()).cached(
+                        StyleRefinement::default().size_full()
+                    ))
                     .child(self.render_drop_zones(terminal_id, cx, &self.active_drag.clone())),
             )
     }
@@ -395,7 +397,9 @@ impl<D: ActionDispatch + Send + Sync> LayoutContainer<D> {
                 .size_full()
                 .min_h_0()
                 .min_w_0()
-                .child(container);
+                .child(AnyView::from(container).cached(
+                    StyleRefinement::default().size_full()
+                ));
         }
 
         let is_horizontal = direction == SplitDirection::Horizontal;
@@ -474,7 +478,9 @@ impl<D: ActionDispatch + Send + Sync> LayoutContainer<D> {
                 .flex_basis(relative(size_percent / 100.0))
                 .min_w_0()
                 .min_h_0()
-                .child(container)
+                .child(AnyView::from(container).cached(
+                    StyleRefinement::default().size_full()
+                ))
                 .into_any_element();
 
             elements.push(child_element);

crates/okena-views-terminal/src/layout/tabs/mod.rs

@@ -251,7 +251,9 @@ impl<D: ActionDispatch + Send + Sync> LayoutContainer<D> {
 
             return v_flex()
                 .size_full()
-                .child(container);
+                .child(AnyView::from(container).cached(
+                    StyleRefinement::default().size_full()
+                ));
         }
 
         let num_children = children.len();
@@ -303,7 +305,7 @@ impl<D: ActionDispatch + Send + Sync> LayoutContainer<D> {
                         })
                         .clone();
 
-                    container
+                    AnyView::from(container).cached(StyleRefinement::default().size_full())
                 }),
             )
     }

crates/okena-views-terminal/src/layout/terminal_pane/render.rs

@@ -189,7 +189,9 @@ impl<D: ActionDispatch + Send + Sync> Render for TerminalPane<D> {
                         .min_w_0()
                         .overflow_hidden()
                         .relative()
-                        .child(self.content.clone())
+                        .child(AnyView::from(self.content.clone()).cached(
+                            StyleRefinement::default().size_full()
+                        ))
                         .when(show_border, |el| {
                             el.child(div().absolute().inset_0().border_1().border_color(border_color))
                         }),

crates/okena-views-terminal/src/overlays/detached_terminal.rs

@@ -314,7 +314,9 @@ impl Render for DetachedTerminalView {
                 div()
                     .flex_1()
                     .min_h_0()
-                    .child(self.content.clone()),
+                    .child(AnyView::from(self.content.clone()).cached(
+                        StyleRefinement::default().size_full()
+                    )),
             )
             .id("detached-terminal-main")
             .on_click(cx.listener(|this, _, window, cx| {

src/simple_root.rs

@@ -4,7 +4,7 @@
 use gpui::{
     AnyView, Bounds, Context, CursorStyle, Decorations, DispatchPhase, Hitbox, HitboxBehavior,
     InteractiveElement, IntoElement, MouseButton, MouseDownEvent, ParentElement, Pixels, Point,
-    Render, ResizeEdge, Size, Styled, Window, canvas, div, point, prelude::FluentBuilder, px,
+    Render, ResizeEdge, Size, StyleRefinement, Styled, Window, canvas, div, point, prelude::FluentBuilder, px,
 };
 
 /// Edge detection zone size (pixels) for CSD resize handles.
@@ -94,7 +94,7 @@ impl Render for SimpleRoot {
                     .absolute(),
                 )
             })
-            .child(self.view.clone())
+            .child(self.view.clone().cached(StyleRefinement::default().size_full()))
     }
 }
 

src/views/panels/project_column.rs

@@ -704,7 +704,9 @@ impl Render for ProjectColumn {
                         .flex_1()
                         .min_h_0()
                         .overflow_hidden()
-                        .child(self.layout_container.clone().unwrap())
+                        .child(AnyView::from(self.layout_container.clone().unwrap()).cached(
+                            StyleRefinement::default().size_full()
+                        ))
                         .into_any_element()
                 } else if is_creating {
                     self.render_creating_state(cx).into_any_element()

src/views/root/render.rs

@@ -181,7 +181,9 @@ impl RootView {
                     .w(px(pixel_width))
                     .flex_shrink_0()
                     .h_full()
-                    .child(col)
+                    .child(AnyView::from(col).cached(
+                        StyleRefinement::default().size_full()
+                    ))
                     .into_any_element();
 
                 elements.push(col_element);
@@ -832,7 +834,9 @@ impl Render for RootView {
                                         div()
                                             .w(px(configured_width))
                                             .h_full()
-                                            .child(self.sidebar.clone())
+                                            .child(AnyView::from(self.sidebar.clone()).cached(
+                                                StyleRefinement::default().size_full()
+                                            ))
                                     )
                                 })
                         }