tag

#oam

2 posts

RetrogamingDeep Dive October 4, 2026 8 min read

Game Boy Advance Affine OBJ: OAM Matrix Slots, Fixed-Point Mapping, and Double Size

Decode GBA affine OBJ state across OAM attributes and interleaved PA/PB/PC/PD slots, then map pixels with signed 8.8 coefficients.

#game-boy-advance#gba#obj

RetrogamingDeep Dive October 4, 2026 7 min read

Follow NES sprite evaluation from primary OAM through eight secondary slots, the diagonal overflow bug, sprite fetches, and scanline-visible state.

#nes#ppu#sprites