Mirror UVs for normal maps

Does Unity supports mirrored UVs for normal maps? It is my understanding that the artist wants to have a full model, but with the final unwrap include only 1/2 a symmetrical normal map, then use mirrored UVs to map it to both halves of the model, but we're unclear on if this is supported by Unity.

If I am understanding you correctly, you are asking if you can take a mesh, (i.e. half of a person) and UV map it, then use a mirror modifier to make it into a symmetrical mesh?

If so, yes Unity supports this.

The process goes as follows:

  1. Create the half mesh in your editing software
  2. Unwrap the UV on the half-mesh
  3. Texture it
  4. In the editing software apply the mirror modifier
  5. save and drag n' drop into unity or export as FBX - whichever.

You should be good-to-go.



Make sure than in the import settings of your objects you select the tangents as “Import”

I know this is an old question, but I'm updating it so if other people are searching for this they'll get some better information.

Technically your normal map will work, it'll just appear to be inverted (creases in will appear to go out, ect.) on the mirrored half. If you're just painting your normal maps in photoshop it probably won't look as bad as if you where baking them from a high poly source.

It's up to the artist to decide whether to do this or not. If it's just on some environment pieces or stuff that won't be close to the camera, go for it. If it's on a character spend the extra time to do it right.

When I'm doing anything with normal maps I make sure my UVs aren't flipped/mirrored. If you have overlapping UVs that's fine, as long as they're not mirrored and not overlapping if you're baking out your normals.