InputCommon:QuarzKB&M: Use KVO to watch window position

CGWindowListCreateDescriptionFromArray would block for up to ~1ms, which isn't a great thing to do on the main emulation thread

2 files changed, 82 insertions, 29 deletions

diff --git a/Source/Core/InputCommon/ControllerInterface/Quartz/QuartzKeyboardAndMouse.h b/Source/Core/InputCommon/ControllerInterface/Quartz/QuartzKeyboardAndMouse.h
index dfcf216e45..e4bdb6e5fb 100644
--- a/Source/Core/InputCommon/ControllerInterface/Quartz/QuartzKeyboardAndMouse.h
+++ b/Source/Core/InputCommon/ControllerInterface/Quartz/QuartzKeyboardAndMouse.h
@@ -8,6 +8,12 @@
 #include "Common/Matrix.h"
 #include "InputCommon/ControllerInterface/CoreDevice.h"
 
+#ifdef __OBJC__
+@class DolWindowPositionObserver;
+#else
+class DolWindowPositionObserver;
+#endif
+
 namespace ciface::Quartz
 {
 std::string KeycodeToName(const CGKeyCode keycode);
@@ -59,13 +65,16 @@ public:
   void UpdateInput() override;
 
   explicit KeyboardAndMouse(void* view);
+  ~KeyboardAndMouse() override;
 
   std::string GetName() const override;
   std::string GetSource() const override;
 
 private:
+  void MainThreadInitialization(void* view);
+
   Common::Vec2 m_cursor;
 
-  uint32_t m_windowid;
+  DolWindowPositionObserver* m_window_pos_observer;
 };
 }  // namespace ciface::Quartz
diff --git a/Source/Core/InputCommon/ControllerInterface/Quartz/QuartzKeyboardAndMouse.mm b/Source/Core/InputCommon/ControllerInterface/Quartz/QuartzKeyboardAndMouse.mm
index 9cc8d07926..9b82ef591c 100644
--- a/Source/Core/InputCommon/ControllerInterface/Quartz/QuartzKeyboardAndMouse.mm
+++ b/Source/Core/InputCommon/ControllerInterface/Quartz/QuartzKeyboardAndMouse.mm
@@ -4,6 +4,7 @@
 #include "InputCommon/ControllerInterface/Quartz/QuartzKeyboardAndMouse.h"
 
 #include <map>
+#include <mutex>
 
 #include <Carbon/Carbon.h>
 #include <Cocoa/Cocoa.h>
@@ -12,6 +13,64 @@
 
 #include "InputCommon/ControllerInterface/ControllerInterface.h"
 
+/// Helper class to get window position data from threads other than the main thread
+@interface DolWindowPositionObserver : NSObject
+
+- (instancetype)initWithView:(NSView*)view;
+@property(readonly) NSRect frame;
+
+@end
+
+@implementation DolWindowPositionObserver
+{
+  NSWindow* _window;
+  NSRect _frame;
+  std::mutex _mtx;
+}
+
+- (NSRect)calcFrame
+{
+  return [_window frame];
+}
+
+- (instancetype)initWithView:(NSView*)view
+{
+  self = [super init];
+  if (self)
+  {
+    _window = [view window];
+    _frame = [self calcFrame];
+    [_window addObserver:self forKeyPath:@"frame" options:0 context:nil];
+  }
+  return self;
+}
+
+- (NSRect)frame
+{
+  std::lock_guard<std::mutex> guard(_mtx);
+  return _frame;
+}
+
+- (void)observeValueForKeyPath:(NSString*)keyPath
+                      ofObject:(id)object
+                        change:(NSDictionary<NSKeyValueChangeKey, id>*)change
+                       context:(void*)context
+{
+  if (object == _window)
+  {
+    NSRect new_frame = [self calcFrame];
+    std::lock_guard<std::mutex> guard(_mtx);
+    _frame = new_frame;
+  }
+}
+
+- (void)dealloc
+{
+  [_window removeObserver:self forKeyPath:@"frame"];
+}
+
+@end
+
 namespace ciface::Quartz
 {
 std::string KeycodeToName(const CGKeyCode keycode)
@@ -149,20 +208,12 @@ KeyboardAndMouse::KeyboardAndMouse(void* view)
   AddCombinedInput("Shift", {"Left Shift", "Right Shift"});
   AddCombinedInput("Ctrl", {"Left Control", "Right Control"});
 
-  NSView* cocoa_view = (__bridge NSView*)view;
-
   // PopulateDevices may be called on the Emuthread, so we need to ensure that
   // these UI APIs are only ever called on the main thread.
   if ([NSThread isMainThread])
-  {
-    m_windowid = [[cocoa_view window] windowNumber];
-  }
+    MainThreadInitialization(view);
   else
-  {
-    dispatch_sync(dispatch_get_main_queue(), ^{
-      m_windowid = [[cocoa_view window] windowNumber];
-    });
-  }
+    dispatch_sync(dispatch_get_main_queue(), [this, view] { MainThreadInitialization(view); });
 
   // cursor, with a hax for-loop
   for (unsigned int i = 0; i < 4; ++i)
@@ -173,26 +224,19 @@ KeyboardAndMouse::KeyboardAndMouse(void* view)
   AddInput(new Button(kCGMouseButtonCenter));
 }
 
-void KeyboardAndMouse::UpdateInput()
-{
-  CGRect bounds = CGRectZero;
-  CGWindowID windowid[1] = {m_windowid};
-  CFArrayRef windowArray = CFArrayCreate(nullptr, (const void**)windowid, 1, nullptr);
-  CFArrayRef windowDescriptions = CGWindowListCreateDescriptionFromArray(windowArray);
-  CFDictionaryRef windowDescription =
-      static_cast<CFDictionaryRef>(CFArrayGetValueAtIndex(windowDescriptions, 0));
-
-  if (CFDictionaryContainsKey(windowDescription, kCGWindowBounds))
-  {
-    CFDictionaryRef boundsDictionary =
-        static_cast<CFDictionaryRef>(CFDictionaryGetValue(windowDescription, kCGWindowBounds));
+// Very important that this is here
+// C++ and ObjC++ have different views of the header, and only ObjC++'s will deallocate properly
+KeyboardAndMouse::~KeyboardAndMouse() = default;
 
-    if (boundsDictionary != nullptr)
-      CGRectMakeWithDictionaryRepresentation(boundsDictionary, &bounds);
-  }
+void KeyboardAndMouse::MainThreadInitialization(void* view)
+{
+  NSView* cocoa_view = (__bridge NSView*)view;
+  m_window_pos_observer = [[DolWindowPositionObserver alloc] initWithView:cocoa_view];
+}
 
-  CFRelease(windowDescriptions);
-  CFRelease(windowArray);
+void KeyboardAndMouse::UpdateInput()
+{
+  NSRect bounds = [m_window_pos_observer frame];
 
   const double window_width = std::max(bounds.size.width, 1.0);
   const double window_height = std::max(bounds.size.height, 1.0);