I was under the impression that it was mostly the mobile GPUs that supported blending a large number of planes at scanout time. I've written software for random

I was under the impression that it was mostly the mobile GPUs that supported blending a large number of planes at scanout time. I've written software for random ARM SoCs where there were a dozen planes or so that you had to program the ordering and bounds of. The first was typically the default framebuffer, another was the cursor, two were the outputs of the hardware video decoders, and the rest were up to the application developer to use. The big desktop GPUs seem to only have the standard framebuffer, a cursor plane, and a small number (<= 2) of overlay planes. It seems that the general consensus is that they tend to have such a ridiculous amount of horsepower that rendering everything into an output buffer and displaying that won't even kick the GPU out of its idle power state. That being said, I had a few hours of fun hacking glxgears and glmark2 to render into the cursor plane on Wayland.