I’ve been trying to fix a UV Overlapping issue for about 2½ hours now.
I am working on a little sandbox project to learn new things, and I use models that I find around the internet. I have 2 models right now that got the UV overlapping error, preventing lightmass being built properly.
Using Blender I have tried so many things to make the UV Overlapping stop. I scaled the UV, moved it around, made sure it was all within the UV Grid, added more channels and everything, but I have managed to make the UV overlap from 22 % to 21.8 % in those 2½ hours…that’s just retarded.
I come here to seek help for the above problem.
If you need pictures, source or anything else, I can provide it. Thanks in advance.
By the way, UV overlapping doesn’t prevent you from building lighting, it just won’t necessarily look right, you can build lighting and if it looks fine then don’t worry about the error.
Models off the internet though usually aren’t suitable for games, so it may be difficult to map them correctly.
Any way, I know they are not suitable, but they will do for this project.
But if it wasn’t because they mess up what the scene looks like, I Wouldn’t care. But they do. A lot actually. So that’s why I need it fixed
I can link the files if that helps? It’s two files.
Have you got the lightmap coordinate index set correctly? If you’ve generated a proper lightmap in Blender (so on the second channel) import the mesh into UE and open it in the Mesh editor. Hit the UV button and make sure from the Dropdown menu that ‘UV Channel 0’ has your UV texture map on and that ‘UV channel 1’ has your Blender lightmap on. In the details pane under Static mesh settings check lightmap coordinate index is set to 1 (the second UV channel in blender).
If that doesn’t help link the files and we can have a look at your UVs.
I’ve had problem when UE4 could not calculate second uv channel properly. The root of problem - different polygons were in same place and had same uv’s, so UE4 treated them like same polygons and have not “shuffled” their uv’s so they basically stay in same place and overlap.
Illustration of problematic mesh(8 cubes)
To solve this you have to manually create UV for Lightmass without overlapping.
