Add Per Channel AO (height), Normal strength, Roughness mod

[TokisanGames]

We can use height as AO for free. We can use per channel AO and strength. I'm currently experimenting with it on our many textures and so far it's something we'll definitely be using on most of our textures.

I'm also finding the need for per channel normal strength, and roughness mod.

[TokisanGames]

I attempted to add height as AO today, however I'm finding that either the indexing or the depth blending operates in a strange square pattern that makes this not possible at the moment. I think this also causes a lot of issues I have when painting textures and attempting to blend them in general.

This will have to wait until we can rework the texturing to a more artist friendly method.

In the meantime AO can be added as a whole by enabling the shader override and adding this in the pbr section. Change 0.4 to taste:

AO = color.a;
AO_LIGHT_AFFECT = 0.4;