A comparison against different memory clearing strategies for the PS2 Graphics Synthesizer
I'm happy to include other strategies if any are suggested.
Simply draws a large 640x448 sprite.
The zbuffer will clear the bottom half. Because depth testing is free, you only have to rasterize half of the amount of pixels.
Instead of causing multiple page breaks, fill in memory a page at a time.
Straightforward, a Double Half Clear on the top half of the frame while the zbuffer clears the bottom.
Because of the mirrored block arrangement in CT32/CT24 vs Z32/Z24, filling in the front half of a page will be mirrored by the zbuffer write, filling in the other half.
Setting FBW 1 essentially stacks the framebuffer vertically in 64x32 pages.
Same configuration as the VIS Clear, but now we set ZBP to FBP. Now we only have to draw 32x2048 sprites.
Thank you to refractionpcsx2 and PSI's PS2TEK for the support and documentation required to preserve these fun optimizations.