[Question] Exclude normal map shading from specific channal

When I plug the normal map on low poly model, the highlight from roughness channel got affect by normal map too (as expect). But I want the roughness channel to treat the model as if it doesn’t have normal map(So the highlight run on low poly mesh not the modified normal shading mesh) . Is it possible to do that? Thank you in advance.

Unplug the normal map then?

I make an eyeball which has normal map to make it concave in the middle (iris) so I want a shading from normal map but I want the the highlight from roughness that run on the whole sphere(which is cornea+sclera) So I won’t unplug normal map.

You might want to invest into a separate mesh for the gloss aspect of the eye, getting a shader that would both have a normal for the iris conclave and cornea is near impossible, yet alone impractical.

Good example

But if you want to use only one layer of mesh, I suggest you look into parralax solutions. There is an example of Golumn’s eyes in marmoset, you could utilize that.

Thanks but even with separated mesh I can’t get clear cornea glass with highlight example here https://docs.unrealengine.com/latest/INT/Engine/Rendering/Materials/HowTo/Transparency/index.html When I decrease the opacity the highlight is fading with it. Is there a way to keep only the rougness specularity highlight and omitt everything else so I get only highlight? OR is there a way to boost only highlight intensity.

The one in example can be achieved simply, set Base color at 1, metallic 1, spec inbetween 1-1000, roughness - depending on how blurred you need, 0.05 works well, opacity at 0.1, set material blend to translucent and in translucent tab set the lighting mode to surface per pixel and set screen space reflections to true. The caviat is that reflections will be screen space, so light wont be able to affect the translucency directly, hence highlights will only come from the environment.

If you dont want to tinker with translucency, search the forums for Warrior scene collab, they have a good explanation of the shader they used for their eyes.