WIP: Optimistically produce a frame at the end of an effect cycle

Co-Authored-By: Thorsten Ball <thorsten@zed.dev>

Cargo.lock

@@ -3255,6 +3255,7 @@ dependencies = [
  "serde",
  "serde_derive",
  "serde_json",
+ "signpost",
  "simplelog",
  "slotmap",
  "smallvec",
@@ -7312,6 +7313,12 @@ dependencies = [
  "rand_core 0.6.4",
 ]
 
+[[package]]
+name = "signpost"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "acde4ef7ee97ad3bac7c4f73ee22ddb71067aa1d427a22efa76284de48eada41"
+
 [[package]]
 name = "simdutf8"
 version = "0.1.4"

crates/gpui/Cargo.toml

@@ -47,6 +47,7 @@ seahash = "4.1"
 serde.workspace = true
 serde_derive.workspace = true
 serde_json.workspace = true
+signpost = "0.1"
 slotmap = "1.0.6"
 smallvec.workspace = true
 smol.workspace = true

crates/gpui/src/app.rs

@@ -652,25 +652,19 @@ impl AppContext {
                     }
                 }
             } else {
-                for window in self.windows.values() {
-                    if let Some(window) = window.as_ref() {
-                        if window.dirty {
-                            window.platform_window.invalidate();
-                        }
-                    }
-                }
-
-                #[cfg(any(test, feature = "test-support"))]
                 for window in self
                     .windows
                     .values()
                     .filter_map(|window| {
                         let window = window.as_ref()?;
-                        (window.dirty || window.focus_invalidated).then_some(window.handle)
+                        window.dirty.then_some(window.handle)
                     })
                     .collect::<Vec<_>>()
                 {
-                    self.update_window(window, |_, cx| cx.draw()).unwrap();
+                    self.update_window(window, |_, cx| {
+                        cx.draw();
+                    })
+                    .unwrap();
                 }
 
                 if self.pending_effects.is_empty() {

crates/gpui/src/window.rs

@@ -341,8 +341,16 @@ impl Window {
         platform_window.on_request_frame(Box::new({
             let mut cx = cx.to_async();
             move || {
-                measure("frame duration", || {
+                signpost::trace_function(42, &[0; 4], || {
-                    handle.update(&mut cx, |_, cx| cx.draw()).log_err();
+                    measure("frame duration", || {
+                        handle
+                            .update(&mut cx, |_, cx| {
+                                cx.window
+                                    .platform_window
+                                    .draw(&cx.window.rendered_frame.scene);
+                            })
+                            .log_err();
+                    })
                 })
             }
         }));
@@ -380,10 +388,12 @@ impl Window {
         platform_window.on_input({
             let mut cx = cx.to_async();
             Box::new(move |event| {
-                handle
+                signpost::trace_function(41, &[0; 4], || {
-                    .update(&mut cx, |_, cx| cx.dispatch_event(event))
+                    handle
-                    .log_err()
+                        .update(&mut cx, |_, cx| cx.dispatch_event(event))
-                    .unwrap_or(false)
+                        .log_err()
+                        .unwrap_or(false)
+                })
             })
         });
 
@@ -1071,9 +1081,7 @@ impl<'a> WindowContext<'a> {
                 .retain(&(), |listener| listener(&event, self));
         }
 
-        self.window
+        self.window.platform_window.invalidate();
-            .platform_window
-            .draw(&self.window.rendered_frame.scene);
         self.window.refreshing = false;
         self.window.drawing = false;
     }