I've stumbled upon a question in your forum related with what I want to achieve and would like to check if it could be used for my purpose. In my case I'm looking into rendering parts of the framebuffer at a different frequency, while preserving other parts (which shouldn't change across frames). So, ideally, I'd like to perform clears in specific areas to achieve that. Am I right in assuming that if do the following I'll be able to preserve partial framebuffer contents on Mali GPUs? So, the intention being to tell the driver I want to invalidate the "custom area" and the proceed with a clear and draw to the remaining areas.
// FRAME 1
// draw everything needed
// FRAME 2-N
glScissor(fromX, fromY, custom_area_width, custom_area_height);
glScissor(0, 0, fbo_width, fbo_height); // full screen
// draw only I care about outside the custom area
I'm aware of transaction elimination, but I'd like to (a) completely avoid rendering to areas I know are not changing and (b) preserve those across frames if possible.
Peter Harris said:* I assume that fbo1 here is an off-screen render target, not the window surface?
It could either be the application's EGL backbuffer or an off-screen FBO. With "window surface" are you referring to the frontbuffer as the post I refer to in the original question?
Peter Harris said: Are you using MSAA with the render target?
Possibly (most likely), yes.
Thanks, let me do some digging here, and get back to you.