search

skyfloogle / red-viper

A Virtual Boy emulator for the 3DS
764 stars 17 forks source link

Account for HOFSTR hardware flaw in h-bias worlds #43

Closed pizzarollsroyce closed 3 months ago

pizzarollsroyce commented 4 months ago

VB hardware will OR the eye "offset" with the param_base instead of adding it to compute the h-bias offset, which results in incorrect behavior if the param_base isn't word-aligned. See http://perfectkiosk.net/stsvb.html#vip_worlds_h_bias

Another selfish fix for Elevated Speed, which exploits this flaw to reduce writes to VRAM

pizzarollsroyce commented 4 months ago

I double checked the behavior against level 3 of Wario Land. H-bias layers that are used for the wavy underwater effect still work.