First off, apologies - I’m a blender newbie, and I’ve been having a ton of difficulty modifying the UV mappings of a 3d arc (kind of shaped like a spectacle lens) to fit the entire UV square. After doing a UV unwrap, this is what I get:
Sorry again if my question seems rather basic, but I haven’t been able to figure out how to do this without having to edit the UV map on a per-vertex basis.
try using the live unwrap function. enable live unwrap, pin the corner vertexes§, then move(G) them to the corners, and the rest of the coordinates will auto-optimize. I don’t know if it will be a perfect square though.