/vr/ - Retro Games

>>7935167
>changing the palette in hblank is relatively easy.
It is not. First, you must determine when hBlank is. This has it's own synchronization issues. Then you have to shut off PPU rendering and set the PPU address pointer to the color you want to change. This is all of the time you have in that hBlank, so, you have to wait for the next scanline. The background color will be the color you are pointing at, so, consider that. While this line is rendering, load the new color you want to change and nametable address you want to restore into the A, X, and Y registers. Wait an appopriate amount of time. Then, when the next hBlank starts, write the new color to palette RAM and restore the nametable address to the PPU address register. If you don't do this in a vertical multiple of 8 then your Y address won't line up properly.
There. You changed one color. If you want to change more, you'll have to sacrifice more scanlines or accept a rainbowy mess drawing on the screen.
now you can properly appreciate how fucking smooth my shit is =)

>>7679872
transition screens are done with smooth playfield scroll in.
it was difficult to get a perfect moving sprite 0 hit for the vertically scrolling background color change but you can accomplish difficult things when you put your mind to it.
>>7696832
video captured from real console