What's the magic behind CAReplicatorLayer?

Question

What I find interesting with CAReplicatorLayer:

• It is able to display a CALayer multiple times with different transforms very efficiently (how?)
• It seems

Answer 1

The special-purpose CALayers like CAReplicatorLayer or CAGradientLayer are able (via private APIs) do execute their drawing directly on the GPU using fast filling or copying. In a sense they are different such that the backing store is not in normal RAM, but directly on the GPU.