CALayer masking in drawLayer:inContext (to avoid layer.cornerRadius performance hit)

gistfile1.m

/*
Source: Apple Developer - Understanding iOS View Compositing
Note: setting view.layer.cornerRadius and .masksToBounds
sends the view for rending to an offscreen buffer.
We want to avoid unnecessary rendering passes. 
Let the context do the work. 
*/

- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx {
	CGRect rect = layer.bounds;
	[[UIBezierPath bezierPathWithRoundedRect:rect
								cornerRadius:10.0] addClip];
	[image drawInRect:rect];
}