feat: add rotate gesture for macOS (#19294)

* feat: add rotate gesture for macOS

* docs: document change

* refactor: rename 'rotate' -> 'rotate-gesture'

* refactor: const float -> float

* forgot one 🤦‍♂️

docs/api/browser-window.md

@@ -614,6 +614,19 @@ Returns:
 
 Emitted on 3-finger swipe. Possible directions are `up`, `right`, `down`, `left`.
 
+#### Event: 'rotate-gesture' _macOS_
+
+Returns:
+
+* `event` Event
+* `rotation` Float
+
+Emitted on trackpad rotation gesture. Continually emitted until rotation gesture is
+ended. The `rotation` value on each emission is the angle in degrees rotated since
+the last emission. The last emitted event upon a rotation gesture will always be of
+value `0`. Counter-clockwise rotation values are positive, while clockwise ones are
+negative.
+
 #### Event: 'sheet-begin' _macOS_
 
 Emitted when the window opens a sheet.

shell/browser/api/atom_api_top_level_window.cc

@@ -246,6 +246,10 @@ void TopLevelWindow::OnWindowSwipe(const std::string& direction) {
   Emit("swipe", direction);
 }
 
+void TopLevelWindow::OnWindowRotateGesture(float rotation) {
+  Emit("rotate-gesture", rotation);
+}
+
 void TopLevelWindow::OnWindowSheetBegin() {
   Emit("sheet-begin");
 }

shell/browser/api/atom_api_top_level_window.h

@@ -73,6 +73,7 @@ class TopLevelWindow : public mate::TrackableObject<TopLevelWindow>,
   void OnWindowScrollTouchBegin() override;
   void OnWindowScrollTouchEnd() override;
   void OnWindowSwipe(const std::string& direction) override;
+  void OnWindowRotateGesture(float rotation) override;
   void OnWindowSheetBegin() override;
   void OnWindowSheetEnd() override;
   void OnWindowEnterFullScreen() override;

shell/browser/native_window.cc

@@ -513,6 +513,11 @@ void NativeWindow::NotifyWindowSwipe(const std::string& direction) {
     observer.OnWindowSwipe(direction);
 }
 
+void NativeWindow::NotifyWindowRotateGesture(float rotation) {
+  for (NativeWindowObserver& observer : observers_)
+    observer.OnWindowRotateGesture(rotation);
+}
+
 void NativeWindow::NotifyWindowSheetBegin() {
   for (NativeWindowObserver& observer : observers_)
     observer.OnWindowSheetBegin();

shell/browser/native_window.h

@@ -256,6 +256,7 @@ class NativeWindow : public base::SupportsUserData,
   void NotifyWindowScrollTouchBegin();
   void NotifyWindowScrollTouchEnd();
   void NotifyWindowSwipe(const std::string& direction);
+  void NotifyWindowRotateGesture(float rotation);
   void NotifyWindowSheetBegin();
   void NotifyWindowSheetEnd();
   void NotifyWindowEnterFullScreen();

shell/browser/native_window_observer.h

@@ -78,6 +78,7 @@ class NativeWindowObserver : public base::CheckedObserver {
   virtual void OnWindowScrollTouchBegin() {}
   virtual void OnWindowScrollTouchEnd() {}
   virtual void OnWindowSwipe(const std::string& direction) {}
+  virtual void OnWindowRotateGesture(float rotation) {}
   virtual void OnWindowSheetBegin() {}
   virtual void OnWindowSheetEnd() {}
   virtual void OnWindowEnterFullScreen() {}

shell/browser/ui/cocoa/atom_ns_window.mm

@@ -72,6 +72,10 @@ bool ScopedDisableResize::disable_resize_ = false;
   }
 }
 
+- (void)rotateWithEvent:(NSEvent*)event {
+  shell_->NotifyWindowRotateGesture(event.rotation);
+}
+
 - (NSRect)contentRectForFrameRect:(NSRect)frameRect {
   if (shell_->has_frame())
     return [super contentRectForFrameRect:frameRect];