Fix title bar height on macOS Tahoe (#11241)

Author: emilk

Cargo.lock

@@ -358,7 +358,7 @@ dependencies = [
  "clipboard-win",
  "image",
  "log",
- "objc2 0.6.1",
+ "objc2 0.6.2",
  "objc2-app-kit 0.3.1",
  "objc2-core-foundation",
  "objc2-core-graphics",
@@ -1244,7 +1244,7 @@ version = "0.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "340d2f0bdb2a43c1d3cd40513185b2bd7def0aa1052f956455114bc98f82dcf2"
 dependencies = [
- "objc2 0.6.1",
+ "objc2 0.6.2",
 ]
 
 [[package]]
@@ -2953,7 +2953,7 @@ dependencies = [
  "bitflags 2.9.1",
  "block2 0.6.1",
  "libc",
- "objc2 0.6.1",
+ "objc2 0.6.2",
 ]
 
 [[package]]
@@ -2963,7 +2963,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "89a09f22a6c6069a18470eb92d2298acf25463f14256d24778e1230d789a2aec"
 dependencies = [
  "bitflags 2.9.1",
- "objc2 0.6.1",
+ "objc2 0.6.2",
 ]
 
 [[package]]
@@ -3984,7 +3984,7 @@ dependencies = [
  "glutin_glx_sys",
  "glutin_wgl_sys",
  "libloading 0.8.8",
- "objc2 0.6.1",
+ "objc2 0.6.2",
  "objc2-app-kit 0.3.1",
  "objc2-core-foundation",
  "objc2-foundation 0.3.1",
@@ -5812,9 +5812,9 @@ dependencies = [
 
 [[package]]
 name = "objc2"
-version = "0.6.1"
+version = "0.6.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "88c6597e14493ab2e44ce58f2fdecf095a51f12ca57bec060a11c57332520551"
+checksum = "561f357ba7f3a2a61563a186a163d0a3a5247e1089524a3981d49adb775078bc"
 dependencies = [
  "objc2-encode",
 ]
@@ -5829,10 +5829,10 @@ dependencies = [
  "block2 0.5.1",
  "libc",
  "objc2 0.5.2",
- "objc2-core-data",
- "objc2-core-image",
+ "objc2-core-data 0.2.2",
+ "objc2-core-image 0.2.2",
  "objc2-foundation 0.2.2",
- "objc2-quartz-core",
+ "objc2-quartz-core 0.2.2",
 ]
 
 [[package]]
@@ -5843,10 +5843,15 @@ checksum = "e6f29f568bec459b0ddff777cec4fe3fd8666d82d5a40ebd0ff7e66134f89bcc"
 dependencies = [
  "bitflags 2.9.1",
  "block2 0.6.1",
- "objc2 0.6.1",
+ "libc",
+ "objc2 0.6.2",
+ "objc2-cloud-kit 0.3.1",
+ "objc2-core-data 0.3.1",
  "objc2-core-foundation",
  "objc2-core-graphics",
+ "objc2-core-image 0.3.1",
  "objc2-foundation 0.3.1",
+ "objc2-quartz-core 0.3.1",
 ]
 
 [[package]]
@@ -5862,6 +5867,17 @@ dependencies = [
  "objc2-foundation 0.2.2",
 ]
 
+[[package]]
+name = "objc2-cloud-kit"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "17614fdcd9b411e6ff1117dfb1d0150f908ba83a7df81b1f118005fe0a8ea15d"
+dependencies = [
+ "bitflags 2.9.1",
+ "objc2 0.6.2",
+ "objc2-foundation 0.3.1",
+]
+
 [[package]]
 name = "objc2-contacts"
 version = "0.2.2"
@@ -5885,6 +5901,17 @@ dependencies = [
  "objc2-foundation 0.2.2",
 ]
 
+[[package]]
+name = "objc2-core-data"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "291fbbf7d29287518e8686417cf7239c74700fd4b607623140a7d4a3c834329d"
+dependencies = [
+ "bitflags 2.9.1",
+ "objc2 0.6.2",
+ "objc2-foundation 0.3.1",
+]
+
 [[package]]
 name = "objc2-core-foundation"
 version = "0.3.1"
@@ -5893,7 +5920,7 @@ checksum = "1c10c2894a6fed806ade6027bcd50662746363a9589d3ec9d9bef30a4e4bc166"
 dependencies = [
  "bitflags 2.9.1",
  "dispatch2 0.3.0",
- "objc2 0.6.1",
+ "objc2 0.6.2",
 ]
 
 [[package]]
@@ -5904,7 +5931,7 @@ checksum = "989c6c68c13021b5c2d6b71456ebb0f9dc78d752e86a98da7c716f4f9470f5a4"
 dependencies = [
  "bitflags 2.9.1",
  "dispatch2 0.3.0",
- "objc2 0.6.1",
+ "objc2 0.6.2",
  "objc2-core-foundation",
  "objc2-io-surface",
 ]
@@ -5921,6 +5948,16 @@ dependencies = [
  "objc2-metal",
 ]
 
+[[package]]
+name = "objc2-core-image"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "79b3dc0cc4386b6ccf21c157591b34a7f44c8e75b064f85502901ab2188c007e"
+dependencies = [
+ "objc2 0.6.2",
+ "objc2-foundation 0.3.1",
+]
+
 [[package]]
 name = "objc2-core-location"
 version = "0.2.2"
@@ -5959,7 +5996,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "900831247d2fe1a09a683278e5384cfb8c80c79fe6b166f9d14bfdde0ea1b03c"
 dependencies = [
  "bitflags 2.9.1",
- "objc2 0.6.1",
+ "objc2 0.6.2",
  "objc2-core-foundation",
 ]
 
@@ -5970,7 +6007,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7282e9ac92529fa3457ce90ebb15f4ecbc383e8338060960760fa2cf75420c3c"
 dependencies = [
  "bitflags 2.9.1",
- "objc2 0.6.1",
+ "objc2 0.6.2",
  "objc2-core-foundation",
 ]
 
@@ -6011,6 +6048,17 @@ dependencies = [
  "objc2-metal",
 ]
 
+[[package]]
+name = "objc2-quartz-core"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "90ffb6a0cd5f182dc964334388560b12a57f7b74b3e2dec5e2722aa2dfb2ccd5"
+dependencies = [
+ "bitflags 2.9.1",
+ "objc2 0.6.2",
+ "objc2-foundation 0.3.1",
+]
+
 [[package]]
 name = "objc2-symbols"
 version = "0.2.2"
@@ -6030,13 +6078,13 @@ dependencies = [
  "bitflags 2.9.1",
  "block2 0.5.1",
  "objc2 0.5.2",
- "objc2-cloud-kit",
- "objc2-core-data",
- "objc2-core-image",
+ "objc2-cloud-kit 0.2.2",
+ "objc2-core-data 0.2.2",
+ "objc2-core-image 0.2.2",
  "objc2-core-location",
  "objc2-foundation 0.2.2",
  "objc2-link-presentation",
- "objc2-quartz-core",
+ "objc2-quartz-core 0.2.2",
  "objc2-symbols",
  "objc2-uniform-type-identifiers",
  "objc2-user-notifications",
@@ -8661,8 +8709,10 @@ dependencies = [
  "jiff",
  "notify",
  "num-traits",
+ "objc2-app-kit 0.3.1",
  "parking_lot",
  "rand 0.8.5",
+ "raw-window-handle",
  "re_analytics",
  "re_build_tools",
  "re_entity_db",
@@ -9564,7 +9614,7 @@ dependencies = [
  "dispatch2 0.2.0",
  "js-sys",
  "log",
- "objc2 0.6.1",
+ "objc2 0.6.2",
  "objc2-app-kit 0.3.1",
  "objc2-core-foundation",
  "objc2-foundation 0.3.1",
@@ -11757,7 +11807,7 @@ dependencies = [
  "jni",
  "log",
  "ndk-context",
- "objc2 0.6.1",
+ "objc2 0.6.2",
  "objc2-foundation 0.3.1",
  "url",
  "web-sys",

Cargo.toml

@@ -276,6 +276,7 @@ notify = { version = "6.1.1", features = ["macos_kqueue"] }
 num-derive = "0.4"
 num-traits = "0.2"
 numpy = "0.24"
+objc2-app-kit = "0.3"
 opentelemetry = { version = "0.30", features = ["metrics"] }
 opentelemetry-appender-tracing = "0.30"
 opentelemetry-otlp = "0.30"
@@ -305,6 +306,7 @@ pyo3-build-config = "0.24.1"
 quote = "1.0"
 rand = { version = "0.8", default-features = false, features = ["small_rng"] }
 rand_distr = { version = "0.4", default-features = false }
+raw-window-handle = "0.6"
 rayon = "1.7"
 regex-lite = "0.1.6"
 rexif = "0.7.5"
@@ -318,8 +320,8 @@ rust-format = "0.3"
 rustdoc-json = "0.9.4"
 rustdoc-types = "0.35.0"
 rustls = { version = "0.23", default-features = false }
-seq-macro = "0.3"
 semver = "1.0.26"
+seq-macro = "0.3"
 serde = { version = "1", features = ["derive"] }
 serde_bytes = "0.11"
 serde_json = { version = "1", default-features = false, features = ["std"] }

crates/viewer/re_ui/Cargo.toml

@@ -64,6 +64,12 @@ url.workspace = true
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 notify.workspace = true # Only used with the `hot_reload_design_tokens` feature
 
+# Mac-specific
+[target.'cfg(target_os = "macos")'.dependencies]
+objc2-app-kit.workspace = true
+raw-window-handle.workspace = true
+
+
 [dev-dependencies]
 egui_kittest.workspace = true
 rand = { workspace = true, features = ["std"] }

crates/viewer/re_ui/README.md

@@ -12,3 +12,5 @@ Rerun GUI theme and helpers, built around [`egui`](https://www.egui.rs/).
 Defines the theme of the Rerun Viewer, and has helpers for constructing some UI elements.
 
 Also contains our fonts and icons.
+
+Run the example with `cargo r -p re_ui --example re_ui_example`

crates/viewer/re_ui/examples/re_ui_example/main.rs

@@ -1,3 +1,5 @@
+// Run the example with `cargo r -p re_ui --example re_ui_example`
+
 mod drag_and_drop;
 mod hierarchical_drag_and_drop;
 mod right_panel;
@@ -157,7 +159,7 @@ impl eframe::App for ExampleApp {
 
         self.show_text_logs_as_notifications();
 
-        self.top_bar(egui_ctx);
+        self.top_bar(_frame, egui_ctx);
 
         egui::TopBottomPanel::bottom("bottom_panel")
             .frame(egui_ctx.tokens().bottom_panel_frame())
@@ -413,8 +415,8 @@ fn parse_url(url: &str) -> Option<CommandPaletteUrl> {
 }
 
 impl ExampleApp {
-    fn top_bar(&mut self, egui_ctx: &egui::Context) {
-        let top_bar_style = egui_ctx.top_bar_style(false);
+    fn top_bar(&mut self, frame: &eframe::Frame, egui_ctx: &egui::Context) {
+        let top_bar_style = egui_ctx.top_bar_style(frame, false);
 
         egui::TopBottomPanel::top("top_bar")
             .frame(egui_ctx.tokens().top_panel_frame())

crates/viewer/re_ui/src/context_ext.rs

@@ -88,7 +88,7 @@ pub trait ContextExt {
         egui::RichText::new(text).color(style.visuals.error_fg_color)
     }
 
-    fn top_bar_style(&self, style_like_web: bool) -> TopBarStyle {
+    fn top_bar_style(&self, _frame: &eframe::Frame, style_like_web: bool) -> TopBarStyle {
         let tokens = self.tokens();
         let egui_zoom_factor = self.ctx().zoom_factor();
         let fullscreen = self
@@ -103,7 +103,31 @@ pub trait ContextExt {
             && crate::fullsize_content(self.ctx().os())
             && !fullscreen;
 
-        let native_buttons_size_in_native_scale = egui::vec2(64.0, 24.0); // source: I measured /emilk
+        let traffic_button_sizes_fallback = egui::vec2(64.0, 24.0); // source: I measured /emilk
+
+        #[cfg(target_os = "macos")]
+        let native_buttons_size_in_native_scale = {
+            use crate::egui_ext::WindowChromeMetrics;
+            use raw_window_handle::HasWindowHandle as _;
+
+            let metrics = _frame
+                .window_handle()
+                .ok()
+                .and_then(|handle| WindowChromeMetrics::from_window_handle(&handle.as_raw()));
+            if let Some(metrics) = metrics {
+                let WindowChromeMetrics {
+                    traffic_lights_size,
+                } = metrics;
+                traffic_lights_size
+            } else {
+                if cfg!(debug_assertions) {
+                    re_log::warn_once!("Failed to measure the size of the mac traffic light area");
+                }
+                traffic_button_sizes_fallback
+            }
+        };
+        #[cfg(not(target_os = "macos"))]
+        let native_buttons_size_in_native_scale = traffic_button_sizes_fallback;
 
         let height = if make_room_for_window_buttons {
             // On mac we want to match the height of the native red/yellow/green close/minimize/maximize buttons.