2.5x UV's Mirror and Overlap

Hello Blenderartists!

I’ve got a question that is worrying me for about a time already. How do you mirror and overlap UV-island in the model. I mean straight in the editing mode (this is crucial in my situation). I know that you can join detach a part, unwrap same part, join as uv, mirror detached part and apply scale. This question is more on the blender’s functionality I suppose.

So, you have a model with a couple of same UV-islands which needs to be mirrored and overlapped. What do you do?

At the moment, I mirror an island, rotate it, snap by a vertex, then weld vertices one by one as you can’t really guess the rotation of the other island. Very exhausting I must say.


When you have 2 (not perfectly) mirrored islands, for example 2 halves of a face:

Select the 2 islands and choose UVs -> Copy Mirrored UV Coords (with F6 you can choose which direction on the x-axis).
Scale 1 island ‘-1’ on the x-axis (press S , X & type ‘-1’).
Then use vertex snap to place them on top of each other.

Thanks Sago! Great tip! I think that is true if you have a mirror modifier on the mesh. Let me explain the situation. What would you do if you have a mesh with some same geometry, but you cannot mirror mesh. And you need to work out uvs to make same mesh geometry share exact uv placement.

Do you mean that the 2 sides are not identically mirrored, and if you use ‘Copy Mirrored UV Coords’ some faces of the UV are floating around?

If that’s the case just pin all the islands you’re happy with, then unwrap again. The floating UV faces will fall back into the main islands.

Sorry if I’m completely wrong, something more visual would make the problem more clear.