Cycles: prevent part of texture from being illuminated (AO, no shine, etc) I see this requested here and there and people like to lecture about how it &quot;isn't realistic&quot;. Solutions that are offered are too niche for my use-case.
I have a throat texture and need part of it to not be illuminated AT ALL. I cannot base this effect off of geometry because the edge flow doesn't match the texture. I need to fake depth for the throat. I am only using a diffuse map and a normal map:

This looks pretty good tbh but that is because his mouth is at a downward angle. Notice that if I create a new BSDF material with a 100% black color and put it on a cube, the problem is obvious:

How can I prevent light from interacting with part of a texture AT ALL?
Ok, so I actually did this before but forgot, and since I don't see this solution anywhere else (until mods come and point it out to me), here is the solution:
Specular.
Create an AO map where the baseline color is &quot;50% gray&quot; (HSV: 0,0,0.5) and the completely occluded areas are 100% black (HSV: 0,0,0). (I make all my grayscale maps &quot;grayscale&quot; color mode but am always disappointed by how little effect that has on file size.) Plug that into the Specular property of your Principled BSDF shader.
Before:

After:

In case that is too subtle...
Before:

After: