Custom PPSSPP shaders

[LunaMoo]

@Rick1974 I was able to reproduce this quarter screen issue of yours through forcing older ogl drivers by placing outdated dll's in ppsspp directory and at least in that case it was caused by pow(x,2), so try this workaround:
  arcadescanlines1.1fix.7z (Size: 2.06 KB / Downloads: 1048)

Edit: also note I think the issue isn't even about outdated dll's, but the fact that they came from drivers for different gpu installed on different pc as the same old drivers, installed normally worked fine with this shader without changes;p.

Edit2: Actually this fix seems like it how should have been done in the first place see POW reference notably this ~ "The result is undefined if x<0" so it works with POW for full screen with that - 0.5 only due to driver interpretation, let's call it luck as following documentation the 3/4 black screen was correct result of this code.