06-01-2022, 10:59 PM
About vertex color formula vertexColor * 2 * baseColor:
That's also the formula the PS1 used (it let's you also brighten textures instead of only darkening them). The neutral point where there's no effect on the texture is vertexColor=0.5 since 2*0.5=1. But if it's like the PS1 it's supposed to be in sRGB space. Starting in Blender 2.8, colors are passed around in linear space, so 0.5 (sRGB) will be passed into the node as 0.22 (linear) and 2*0.22=0.44 which makes things too dark. So you can try using a factor of about 4.6 instead of 2 to keep the neutral point neutral. I found this worked pretty well for PS1 models I tried. Unfortunately it loses accuracy as you move away from vertexColor=0.5, but maybe you can try it and see if it's any better than changing the global exposure.
That's also the formula the PS1 used (it let's you also brighten textures instead of only darkening them). The neutral point where there's no effect on the texture is vertexColor=0.5 since 2*0.5=1. But if it's like the PS1 it's supposed to be in sRGB space. Starting in Blender 2.8, colors are passed around in linear space, so 0.5 (sRGB) will be passed into the node as 0.22 (linear) and 2*0.22=0.44 which makes things too dark. So you can try using a factor of about 4.6 instead of 2 to keep the neutral point neutral. I found this worked pretty well for PS1 models I tried. Unfortunately it loses accuracy as you move away from vertexColor=0.5, but maybe you can try it and see if it's any better than changing the global exposure.