[osx] Use NSTrackingInVisibleRect for mouse movement tracking (#21996)

* [osx] Use NSTrackingInVisibleRect for tracking mouse movement

* nit: comment

* Update native/Avalonia.Native/src/OSX/AvnView.mm

Co-authored-by: Max Katz <maxkatz6@outlook.com>

---------

Co-authored-by: Max Katz <maxkatz6@outlook.com>

Author: drasticactions

native/Avalonia.Native/src/OSX/AvnView.mm

@@ -80,7 +80,17 @@ -(AvnView*)  initWithParent: (TopLevelImpl*) parent
     [self setLayerContentsRedrawPolicy: NSViewLayerContentsRedrawDuringViewResize];
 
     _parent = parent;
-    _area = nullptr;
+
+    // NSTrackingInVisibleRect makes AppKit follow the visible bounds of the view.
+    // Because of this, the tracking area does not need to change on resize.
+    // Do not remove and add the area again on each live-resize tick.
+    // If you do, AppKit queues synthetic enter and exit events with stale locations.
+    // These events corrupt the pointer position after a resize and force it to the top left.
+    NSTrackingAreaOptions options = NSTrackingActiveAlways | NSTrackingMouseMoved |
+        NSTrackingMouseEnteredAndExited | NSTrackingEnabledDuringMouseDrag | NSTrackingInVisibleRect;
+    _area = [[NSTrackingArea alloc] initWithRect:NSZeroRect options:options owner:self userInfo:nullptr];
+    [self addTrackingArea:_area];
+
     _lastPixelSize.Height = 100;
     _lastPixelSize.Width = 100;
     [self registerForDraggedTypes: @[@"public.data", GetAvnCustomDataType()]];
@@ -128,25 +138,12 @@ -(void)setFrameSize:(NSSize)newSize
 {
     [super setFrameSize:newSize];
 
-    if(_area != nullptr)
-    {
-        [self removeTrackingArea:_area];
-        _area = nullptr;
-    }
-
     auto parent = _parent.tryGet();
     if (parent == nullptr)
     {
         return;
     }
 
-    NSRect rect = NSZeroRect;
-    rect.size = newSize;
-
-    NSTrackingAreaOptions options = NSTrackingActiveAlways | NSTrackingMouseMoved | NSTrackingMouseEnteredAndExited | NSTrackingEnabledDuringMouseDrag;
-    _area = [[NSTrackingArea alloc] initWithRect:rect options:options owner:self userInfo:nullptr];
-    [self addTrackingArea:_area];
-
     parent->UpdateCursor();
 
     auto fsize = [self convertSizeToBacking: [self frame].size];
@@ -258,8 +255,12 @@ - (void)mouseEvent:(NSEvent *)event withType:(AvnRawMouseEventType) type
         return;
     }
 
-    NSPoint eventLocation = [event locationInWindow];
-    
+    // AppKit synthesizes enter and exit events for the tracked geometry.
+    // They can have stale locations. Use the current pointer location instead.
+    NSPoint eventLocation = event.type == NSEventTypeMouseEntered || event.type == NSEventTypeMouseExited
+        ? [[self window] mouseLocationOutsideOfEventStream]
+        : [event locationInWindow];
+
     auto viewLocation = [self convertPoint:NSMakePoint(0, 0) toView:nil];
 
     auto localPoint = NSMakePoint(eventLocation.x - viewLocation.x, viewLocation.y - eventLocation.y);
@@ -392,7 +393,10 @@ - (void)mouseEvent:(NSEvent *)event withType:(AvnRawMouseEventType) type
         parent->TopLevelEvents->RawMouseEvent(type, pointerType, timestamp, modifiers, point, delta, pressure, xTilt, yTilt);
     }
 
-    [super mouseMoved:event];
+    // This handler is shared by all mouse event types. Only real mouse-moved
+    // events must continue up the responder chain as mouseMoved:
+    if (event.type == NSEventTypeMouseMoved)
+        [super mouseMoved:event];
 }
 
 - (BOOL) resignFirstResponder
@@ -560,7 +564,10 @@ - (void)swipeWithEvent:(NSEvent *)event
 
 - (void)mouseEntered:(NSEvent *)event
 {
-    [self mouseEvent:event withType:Move];
+    // If the pointer is not inside the view, the enter event is false. Ignore it.
+    NSPoint location = [self convertPoint:[[self window] mouseLocationOutsideOfEventStream] fromView:nil];
+    if (NSPointInRect(location, self.bounds))
+        [self mouseEvent:event withType:Move];
     [super mouseEntered:event];
 }