cocoa_common: use a tracking area to handle mouse events

This change which also flipse the coordinate system of the view, greatly
simplifies the mouse event handling code.

There are still some uglities mostly related to the cursor visibility
code. For instance the core doesn't show the cursor when it receives a mouse
leave event.

video/out/cocoa_common.m

@@ -52,9 +52,10 @@
 @end
 
 @interface GLMPlayerOpenGLView : NSView
+@property(nonatomic, retain) NSTrackingArea *tracker;
 @property(nonatomic, assign) struct vo *videoOutput;
+- (BOOL)containsMouseLocation;
 - (void)recalcDraggableState;
-- (BOOL)containsCurrentMouseLocation;
 - (void)mouseEvent:(NSEvent *)theEvent;
 @property(nonatomic, assign, getter=hasMouseDown) BOOL mouseDown;
 @end
@@ -162,13 +163,9 @@ static void vo_cocoa_set_cursor_visibility(struct vo *vo, bool visible)
     struct vo_cocoa_state *s = vo->cocoa;
 
     if (visible) {
-        // show cursor unconditionally
         CGDisplayShowCursor(kCGDirectMainDisplay);
-    } else if (vo->opts->fullscreen &&
-               [s->view containsCurrentMouseLocation] &&
-               ![s->view hasMouseDown]) {
-        // only hide cursor if in fullscreen and the video view contains the
-        // mouse location
+    } else if (vo->opts->fullscreen && ![s->view hasMouseDown] &&
+               [s->view containsMouseLocation]) {
         CGDisplayHideCursor(kCGDirectMainDisplay);
     }
 }
@@ -322,7 +319,6 @@ static void create_window(struct vo *vo, uint32_t d_width, uint32_t d_height,
     [s->window setRestorable:NO];
     [s->window setContentView:s->view];
     [s->view release];
-    [s->window setAcceptsMouseMovedEvents:YES];
     [s->glContext setView:s->view];
     s->window.videoOutput = vo;
     s->view.videoOutput   = vo;
@@ -798,14 +794,35 @@ int vo_cocoa_cgl_color_size(struct vo *vo)
         [self setContentSize:ns];
     }
 }
+
 @end
 
 @implementation GLMPlayerOpenGLView
+@synthesize tracker = _tracker;
 @synthesize videoOutput = _video_output;
 @synthesize mouseDown = _mouse_down;
-- (BOOL)acceptsFirstResponder { return YES; }
-- (BOOL)becomeFirstResponder { return YES; }
-- (BOOL)resignFirstResponder { return YES; }
+// mpv uses flipped coordinates, because X11 uses those. So let's just use them
+// as well without having to do any coordinate conversion of mouse positions.
+- (BOOL) isFlipped { return YES; }
+
+- (id)initWithFrame:(NSRect)frame {
+    if (self = [super initWithFrame:frame]) {
+        NSTrackingAreaOptions trackingOptions =
+            NSTrackingEnabledDuringMouseDrag |
+            NSTrackingMouseEnteredAndExited | NSTrackingMouseMoved |
+            NSTrackingActiveInActiveApp;
+
+        self.tracker =
+            [[[NSTrackingArea alloc] initWithRect:[self bounds]
+                                          options:trackingOptions
+                                            owner:self
+                                         userInfo:nil] autorelease];
+
+        [self addTrackingArea:self.tracker];
+    }
+
+    return self;
+}
 
 - (NSPoint)mouseLocation
 {
@@ -813,51 +830,53 @@ int vo_cocoa_cgl_color_size(struct vo *vo)
     return [self convertPoint:wLoc fromView:nil];
 }
 
-- (NSPoint)mouseLocationUpperLeft
+- (BOOL)containsMouseLocation
 {
-    NSPoint loc = [self mouseLocation];
-    loc.y = - loc.y + [self bounds].size.height;
-    return loc;
-}
-
-- (BOOL)containsCurrentMouseLocation
-{
-    NSRect vF   = [[self.window screen] visibleFrame];
-    NSRect vFR  = [self.window convertRectFromScreen:vF];
-    NSRect vFRV = [self convertRect:vFR fromView:nil];
+    NSRect vF  = [[self.window screen] visibleFrame];
+    NSRect vFW = [self.window convertRectFromScreen:vF];
+    NSRect vFV = [self convertRect:vFW fromView:nil];
 
     // clip bounds to current visibleFrame
-    NSRect clippedBounds = CGRectIntersection([self bounds], vFRV);
+    NSRect clippedBounds = CGRectIntersection([self bounds], vFV);
     return CGRectContainsPoint(clippedBounds, [self mouseLocation]);
 }
 
+- (BOOL)acceptsFirstResponder { return YES; }
+- (BOOL)becomeFirstResponder { return YES; }
+- (BOOL)resignFirstResponder { return YES; }
+
 - (void)recalcDraggableState
 {
     struct vo *vo = self.videoOutput;
     BOOL movable  = NO;
 
     if (!vo->opts->fullscreen) {
-        NSPoint loc = [self mouseLocationUpperLeft];
+        NSPoint loc = [self mouseLocation];
         movable = !mp_input_test_dragging(vo->input_ctx, loc.x, loc.y);
     }
 
     [self.window setMovableByWindowBackground:movable];
 }
 
+- (void)mouseEntered:(NSEvent *)event
+{
+    // do nothing!
+}
+
+- (void)mouseExited:(NSEvent *)event
+{
+    cocoa_put_key(MP_KEY_MOUSE_LEAVE);
+    vo_cocoa_set_cursor_visibility(self.videoOutput, true);
+}
 
 - (void)signalMouseMovement:(NSEvent *)event
 {
-    if ([self containsCurrentMouseLocation]) {
-        NSPoint loc = [self mouseLocationUpperLeft];
-        vo_mouse_movement(self.videoOutput, loc.x, loc.y);
-        [self recalcDraggableState];
-    } else {
-        cocoa_put_key(MP_KEY_MOUSE_LEAVE);
-    }
+    NSPoint p = [self convertPoint:[event locationInWindow] fromView:nil];
+    vo_mouse_movement(self.videoOutput, p.x, p.y);
 }
 
-- (void)mouseMoved:(NSEvent *)evt     { [self signalMouseMovement:evt]; }
-- (void)mouseDragged:(NSEvent *)evt   { [self signalMouseMovement:evt]; }
+- (void)mouseMoved:(NSEvent *)event   { [self signalMouseMovement:event]; }
+- (void)mouseDragged:(NSEvent *)event { [self signalMouseMovement:event]; }
 - (void)mouseDown:(NSEvent *)evt      { [self mouseEvent:evt]; }
 - (void)mouseUp:(NSEvent *)evt        { [self mouseEvent:evt]; }
 - (void)rightMouseDown:(NSEvent *)evt { [self mouseEvent:evt]; }