Open Radar

 
Summary:
Calling -[NSWindow invalidateShadow] no longer updates the shadow shape in a transparent borderless NSWindow with a shadow. The stale shadow from the first paint remains.

Steps to Reproduce:
1. Download the attached file and save it as main.m.
2. Compile and run it with clang++ main.m -framework Cocoa -o test && ./test
3. Wait for two seconds.

Expected Results:
There should be a blue circle with a shadow around it.

Actual Results:
The blue circle doesn't have a shadow. Instead, there is a shadow in the place where there was a red circle. invalidateShadow failed to update the shadow.

Version:
10.12 Beta (16A201w)

Notes:


Configuration:


Attachments:
'main.m' was successfully uploaded.

Contents of main.m reproduced here for convenience:

/**
 * Save as main.m.
 * Compile and run using: clang++ main.m -framework Cocoa -o test && ./test
 *
 * This program creates a borderless window with a transparent background, and a shadow.
 * It draws a red circle into it. After two seconds, it repaints, and draws a blue circle
 * in a different location. Then it calls -[NSWindow invalidateShadow] so that the shadow
 * is updated to be around the blue circle instead of around the red circle.
 *
 * However, on 10.12 Beta (16A201w), invalidateShadow has no effect and the stale shadow remains.
 **/

#import <Cocoa/Cocoa.h>

@interface TestView: NSView
{
  bool _firstDraw;
}

@end

@implementation TestView

- (id)initWithFrame:(NSRect)aFrame
{
  if (self = [super initWithFrame:aFrame]) {
    _firstDraw = YES;
  }
  return self;
}

- (void)drawRect:(NSRect)rect
{
  if (_firstDraw) {

    // Draw a red circle in the bottom left corner.
    NSRect r = NSMakeRect(10, 10, 50, 50);
    NSBezierPath* circlePath = [NSBezierPath bezierPath];
    [circlePath appendBezierPathWithOvalInRect: r];
    [[NSColor redColor] set];
    [circlePath fill];
    _firstDraw = NO;

    // trigger second draw.
    [self performSelector:@selector(invalidate) withObject:nil afterDelay:2.0];

  } else {

    // Draw a blue circle further up and to the right from the right circle.
    NSRect r = NSMakeRect(100, 70, 50, 50);
    NSBezierPath* circlePath = [NSBezierPath bezierPath];
    [circlePath appendBezierPathWithOvalInRect: r];
    [[NSColor blueColor] set];
    [circlePath fill];

    // Invalidate the window shadow.
    [[self window] performSelector:@selector(invalidateShadow) withObject:nil afterDelay:0.0];

  }
}

- (void)invalidate
{
  [self setNeedsDisplay:YES];
}

- (void)mouseUp:(NSEvent*)event
{
  // Shut down on double click.
  if ([event clickCount] >= 2) {
    [NSApp terminate:self];
  }
}

@end

int
main (int argc, char **argv)
{
  NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init];

  [NSApplication sharedApplication];
  [NSApp setActivationPolicy:NSApplicationActivationPolicyRegular];

  int style = NSBorderlessWindowMask;
  NSRect contentRect = NSMakeRect(400, 300, 300, 400);
  NSWindow* window = [[NSWindow alloc] initWithContentRect:contentRect
                                       styleMask:style
                                         backing:NSBackingStoreBuffered
                                           defer:NO];
  [window setHasShadow:YES];
  [window setBackgroundColor:[NSColor clearColor]];

  NSView* view = [[TestView alloc] initWithFrame:NSMakeRect(0, 0, contentRect.size.width, contentRect.size.height)];
    
  [window setContentView:view];
  [NSApp activateIgnoringOtherApps:YES];
  [window makeKeyAndOrderFront:window];

  [NSApp run];

  [pool release];
  
  return 0;
}