05-05-2014, 07:34 AM
DS has a very unusual line-based rasterizer which is non-trivial to emulate accurately with a regular PC gpu. Also, it renders at very small resolutions which makes a software rasterizer fast. The PSP's GPU, while it has a few oddities, is more standard and renders at twice the resolution so more suitable to emulate with a PC gpu.
It could of course also just be a case of a bad implementation in the DS emu.
It could of course also just be a case of a bad implementation in the DS emu.