CoreAnimation performance profiling - CAReplicatorLayer with CAShapeLayer

Question

I'm making an app that relies on CoreAnimation. It has got a CAReplicatorLayer and as a sublayer a CAShapeLayer. When having 12 replications and then animating the path (changing it on touchMoved) there's a significant reduction in FPS once the graphics get bigger on screen (about 12-20 fps).

The time profiler shows about 10 % CPU Utilization, the Open GL ES Driver profiler reports about 90-97% "Render Utilization" and 40-50 % "Tiler Utilization".

This guide explains these two words but not to a great detail. Can anybody explain what these two are exactly? Apple Docs

Apparently the high Render Utilization is the problem, so what can I do to improve the performance?

Answer 1

The solution to this was to remove all UI elements with transparency from the screen (or setting them to opaque).

The fillrate suffers highly when rendering an animated CAShapeLayer under or above UI elements with transparency.

After optimizing this, the render utilization went down to 30-40 percent.