It's an interesting idea, but how would updating individual tiles at different rates appear to the user? Obviously if some parts of the frame remain static you could delay updating those, but how would it look in cases where the entire frame has changed such as during a camera pan? And how would it work with post effects like motion blur or DOF? Maybe it would look good at very high frame rates, but would the individual tiles updates become visible if your app encounters slowdown and FPS drops below 30? It's an interesting idea, and thanks for providing more info. However, I'd need to see a proof of concept, including post effects, before I considered it further.