Bug: Lightmapped4way results in weird problems

Hello! New here, but definitely not to mapping. I’ve been mapping for over a decade at this point. I recently returned to Source engine after a long time in UE and it’s been well…challenging. One of the issues I’m facing is with Lightmapped4way materials for displacements. There’s this strange error where, if a displacement is viewed at a certain angle, the fourth texture (ALWAYS the fourth) gets very dark, and turns either brown or a muddy blue. There also looks to be some other texture mapped onto it, I sometimes see striations. I’ve checked the .vmt and couldn’t find anything off about it.


As you can see, the problem is pretty glaring.

Here is my vmt:

Any help is greatly appreciated. I’ll definitely stick around and help whoever I can with their issues. Cheers!

You seem to have a lot of parameters in your vmt. Maybe remove any non essential lines and test it out to see wether those are causing issues

Hey there, I recreated the .vmt using VMT Editor 1.3.9 but the issue persists. I think what I will do as a workaround is to simply use the first three textures and disregard the fourth, blending between three textures is better than just two, I suppose. If I ever find a solution I’ll be sure to post it here.