What's the difference between overlapping and wrapping uvs?

just to further expand on this. for the lightmap all objects must be unwrapped in the 0-1 space for both U and V and must not be overlapping. wrapping and overlapping are fine for other purposes (although not for baking normals).

and please mark this problem as answered if it is.

Hi Nuclear,

Thanks for your input! And yes, I already marked as answered after my comment.


I was getting errors about “Object has overlapping uvs” on my meshes not having secound UV channels, I fixed that following the advice on here by creating or importing a second UV channel without any overlap. I then chose this light channel in the lightmass index, but after building lighting now the error has changed to “Object has wrapping uvs”. What’s the difference here?

Are wrapping UV’s okay?


No, wrapping UVs are not okay. I’m not an artist, but I hope my Paint Skills are enough for this.

So, make sure your lightmap UVs are in the 0-1 space.

Excellent, that makes total sense! Thanks alot for your answer, your paint skills are more than enough =)