How to UV unwrap an object with mirror modifier?

Hello. Thank you for watching.

I’m struggling with UV-unwrap an object which has a mirror modifier.

After some research on the internet, I understood that I could UV-unwrap the mesh of the mirror side by checking “U” on the mirror modifier and checking “modified” on the display panel of the UV editor type.
But how can I UV-unwrap the object which has a mirror modifier without separating the right side (real object) and the left side (mirror side)?

For example, the UVmap of the image below is ideal, which is from the object without mirror modifier. How can I make the same UVmap from the object with mirror modifier, which is red one in this case.

The reason why I want them to be connected is because I want to draw continuous scars on it

I’m so sorry for my bad Englisn and bad explanation. I’d appreciate if you could help me.


uvmirror.blend (527 KB)

Rotate the uvs so the centre line is as vertical as you can get
Select the points you want on the centre line in the uv editor.
Align them on the x axis (W / Align X)
If they don’t perfectly align scale them on the x axis (S X 0) so they are vertical
Pin these points (shortcut P) so they don’t move when you unwrap. The points will turn red
Unwrap again

Wooooow!! Thank you very much!

One more question, please?
When I choose “export UV layout”, the mirror side doesn’t appear.
Also, when I turn from view to paint mode, the mirror disappears.
Any solution?

In the UV export settings enable the ‘Modified’ option to export the resulting effect of the modifiers

Duplicate object, apply modifiers, paint, save image, apply image to original

Oh, i didn’t expect the button appears there. Undetectable.
Thank you very much.