/vr/ - Retro Games

>>10436380
Well, triggering DMA off an hblank interrupt and messing with the video registers is an obvious use for DMA and many SNES games do exactly the same thing. Not necessarily to increase colour depth, but for many other purposes. The hblank interrupts are fundamental to how the mode 7 effect used in F-Zero and other games works. The scaling factor of the background is changed per scanline to create a perspective effect. In pic related, Konami change the background scroll at the chasm to make the background layer scroll both up and down at the same time and also darken the scanlines at the chasm to make the lava look like it is descending.