blend

I managed to get the affect of compositing multiple CALayers by drawing them directly into a UIView’s graphics context. -(void)drawRect:(CGRect)rect { CGContextRef c = UIGraphicsGetCurrentContext(); CGContextSetBlendMode(c, kCGBlendModeDifference); [myLayer drawInContext:c]; } BTW, I did not add the layers as sublayers of the view’s layer (that is I never called [myView.layer addSublayer:myLayer])