I have black and screwed up materials after building lights. Images below.
I found a lot of posts about overlapping and wrapping UV’s problems and the basic responses have been to go back into the modeling program and fix it. But I bought these models and do not have access to the original source files. So how do you fix it in that case short of importing the mesh into Maya or something and starting the UV mapping process all over? In the good old UDK I would generate unique UV’s, but that option is gone for some reason and I have already played with the Generate Lightmap UVs check box to no result changes at all. The wierd thing is that both models below are using the same materials, are from the same purchased source, and both have UV maps that look like spider webs. One works, one does not. ANy help would be appreciated. I have bought a **** ton of models from these guys back with UDK and this is very common on let’s say 600+ models I have. Thanks Everyone…
In the Mesh editor window, there is an option to generate new UV coordinates for light mapping.
Use that, and make sure you select the new UV coordinate set index as the light map coordinate index for the mesh.
Now, your models say there are 6 UV coordinate sets. That’s … exceedingly large. Whoever modeled these models, did it to some rather uncommon specification, and/or using tools or techniques that have never been a best practice.
Thanks so much for responding. I’m just waiting for the Engine to spool up so I can give it a try. They are commercial models and I’m unfamiliar with other engines but maybe they made them to be universal? I’m guessing to be honest, I don’t know how Unity or Torque works on that stuff. But I’ll post back here if this works so others can see the results.
No, neither Unity nor Torque can make use of 6 UV channels. I know of no engine that can. It looks to me just like sloppy exporting, but I’d prefer to think they had some reason to do it, rather than just assume they’re idiots
The reason may be as simple as the tool they’re using exports one UV channel per sub-material they use for some reason (which, in turn, would also be non-standard, but who knows what their setup is?)
Maybe they export two separate UV channels, and each of them has a tangent basis? That would make for 6 sets. But if the second coordinate set is not useful for light maps, then what is it good for? Detail textures?
Anyway, Unreal does an OK-ish job of building light map coordinates for meshes for me (not great, but sufficient to get the job done.) Good luck!
Well, half of them where able to be fixed by setting the new UV light map index. The other half I had to open in Maya LT and then re-export. I won’t name the specific web site they where purchased from but it was one of the top search results (not Turbosquid) and I will say they worked flawless in UDK so something got lost along the way. But Oh well, problem is solved. Thanks for the help and suggestions.
