Previously mistakenly used the BGR format instead of the RGB.
Probably won't make much of a difference for anything, but may affect #17881
if my theory about it is correct.
Also minor cleanups.
Might be helpful to diagnose performance problems on user devices.
Additionally, moves the texture replacement controls to the top. They
should probably be moved somewhere else entirely...
See #17918
Haven't been using these for a while.
I've come to the conclusion here that I think it's better to try to
deal with the issues using safe workarounds like copies, instead of
relying on features with somewhat iffy driver support that are not
universal across APIs anyway.
This is a conceptually cool trick that just doesn't seem to be worth
it, compared to the old approach of copy + blend-in-shader. I haven't
found any game that benefits more than absolutely minimally, and having
two paths to test isn't great, when the win is so small.
So I'm disabling it. I'm keeping the code for now, but might clear it
out later.
Fixes#17069
Saves about 0.75MB of VRAM, but mainly just to clean things up.
I think I meant to use this one instead of grabbing the one from
DrawEngine in the TextureCache.
