Android Rendering: Is actually in the end everything rendered via OpenGL

Question

Is actually in the end everything rendered via OpenGL in Android. I have already checked out this video https://youtu.be/zdQRIYOST64 and the relevant documents. And it seems that not all is rendered via OpenGL or maybe Vulkan nowadays. But when it is not rendered via this, how is it rendered, via some internal stuff inside the SurfaceFlinger? Can someone show up the way through the code from the application level to the very last point before the hardware?

Answer 1

I have asked @Romain Guy on twitter to answer this question and this is his answer https://twitter.com/romainguy/status/1272314819333337090

Apps are rendered pretty much entirely with OpenGL yes. SurfaceFlinger avoids using the GPU whenever possible and uses dedicated compositing hardware instead (hardware composer). But sometimes it falls back to GL.