I created a human head. In order to put some texture on it, I would like to create
an UV map (as described in so many tutorials).
So i put some seams on the head, and want to unwrap it. But the UV-image just stays empty.
When I try it with any other basic object (e.g. a newly created UV-sphere or a box) it works. The UV image shows a correct 2D image of the objects surface.
But not for my created head.
Is there anything else required for an object to be able to be UV-mapped?