Issue importing skinned mesh with wrong materials on some polygons.

I have imported a skeletal mesh and for some reason im getting very odd results. I am new to unreal so forgive any ignorance. The mesh uses several materials and for some reason it is exporting it with weird errors. For instance if you notice the screenshot… a couple of polys along the waste have the hair material applied to them… when they are skin material inside maya. wtf? … same thing with a some eyelashes… one set of eyelashes is correct while another is set to an entirely different material. It makes no logical sense to me. Any ideas what is happening here? again see the screenshot…

-have you applied the materials to the right material slots in the engine?
-are you 100% sure that you have applied the material to the right vertices? -> just check it again :slight_smile:
-could it be that there is probably something in the mesh which will be visible in the ue4 -> e.g a cloth part that is overlapping with the character mesh

Its maya… i dont know how else to apply a material. You select the polygons… and right click on the material and hit apply material. Pretty straight forward. It comes in correct in unity3d. But not in unreal 4. I have nothing special in this… nothing overlapping… its a character… with several materials… on the same skeleton all in 1 mesh. Makes no sense to me. I made the jump to unreal thinkn this was going to be easy…since it works in unity3d but so far im frustrated… I cant even get a model in the engine correct.

If it helps, before i bound it the material used to be multiple meshes that were merged… … at that wasteline combined then merged the verts… then bound to hte skeleton after… no history… And this issue occurs other places. like hte eyelashes… Part of hte eyelashes… like literally the back face of one eyelash has this issue and the flipped side has no issue. All the eyelashes both sides share the hair material in maya.

In terms of material slots… the hair and those polys on the waste is 1 material slot in engine, but in maya that isnt like that… those couple of polys on the waste belong to the skin material in maya. Like its not a question of which materials are applied to what… its an issue of the polys being grouped together on 1 material are no longer on that material or grouped together in engine… they now belong to a different material entirely … while most of hte skin retained the skin… those 2 polys that are part of the skin somehow turned into hair material.

is it better to detach different materials into seperate meshes before binding them to the skeleton?

Also fun fact… if i remove the skeleton the model comes in correct material wise. Any info?

When i export the mesh with no skeleton and just as a static mesh… the materials are fine, but if i export the skeleton with the mesh the materials are not fine… have those issues like in the screenshot.

This problem is kind of a show stopper. I cant move forward until I know what to do to fix this. Does anyone have any ideas?

Just noticed when i import the fbx file itself back into maya… it also has the same error… so its somehow an fbx export issue. I tried exporting again by triangulating some quads manually to test and it seems it was the exporters “triangulate” feature that was messing things up. Anyone with similiar issues should disable that checkbox in the exporter.

It must have been rough figuring this out on your own, but thanks for the heads up on the outcome because I honestly didn’t even know about that and I think you are likely not the only person who will have this issue. Hopefully you don’t see this issue going forward!