Fill opaque parts of NSImage with color

maskNSImage.c

+ (NSImage *)maskImageNamed:(NSString *)name color:(NSColor *)color
{
	NSImage *image = [NSImage imageNamed:name];
	CGRect rect = CGRectMake(0, 0, image.size.width, image.size.height);
    CGContextRef c = MyCreateBitmapContext(image.size.width, image.size.height);
 	[image drawInRect:rect fromRect:NSZeroRect operation:NSCompositeSourceOver fraction:1.0];
 	CGContextSetFillColorWithColor(c, [color CGColor]);
	CGContextSetBlendMode(c, kCGBlendModeSourceAtop);
	CGContextFillRect(c, rect);
    CGImageRef ciImage =  CGBitmapContextCreateImage(c);
    CGContextDrawImage(c, rect, ciImage);
	NSImage *newImage= [[[NSImage alloc] initWithCGImage:ciImage size:image.size] autorelease];
     CGContextRelease(c);
    CGImageRelease(ciImage);
    return newImage;
}