Maybe I’m just overlooking something obvious but I can’t think of a way to make a material element disabled, that is not being rendered at all other than assign a material that is completely transparent which is obviously a waste since the engine would probably try to render the triangles anyway.
The concrete case is that I want to assign different material elements with the same texture to body parts so that I can disable them when they are covered by clothes, for instance the upper arm when the character is wearing a jacket.
There is no way to remove a material ID in Unreal as far as i know. You’ll have to do something like what ViceVersa suggested. Or you can create a mask for that part of the mesh in your modeling program, keeping that part in the same material ID as the rest of the body, and then use material layers inside Unreal to separate/merge that part’s material by using that mask.
Theres a node in material editor called IF. You can make a scalar parameter and use that to switch between 2 differwnt textures (thr second one would have the body part you want temoved erased from the texture) then make a dynamic material instance, and you can set the value of the scalar parameter in other blueprints
This seems to be the only way then. The other suggestion with the layered materials seems overkill for my simple problem then.
It’s a shame that there is no way to turn off a hole material in a mesh, this seems to be a very important part for modular meshes in my view.
Although I think that maybe this may be more expensive in terms of render time than to just leave the covered area unchanged and have it rendered, it would improve the visual quality by not having covered sections poke through the clothing in some animations.