Every view is re-rendered, even those without dirty render objects. Attaching a video with quartz debug visualizing screen updates.

Known problems

Some things we need to figure out before we can do this optimization:

1. External textures. When an external texture changes, the framework isn’t aware of which views are dirty. Instead, the engine schedules a new frame and lets the framework re-render all views. We’ll need to update the framework to be aware of which views are affected when an external texture changes so that it re-renders just those views.
2. Android platform views. This works similar to external textures.
3. More?