Pak: That's what I am doing. I calculate UV polygon area, and corresponding surface area of the geometric poly, and find the ratio between those, and scale each element by the required amount. Works pretty well.
I think shell definition through surfaces is not the best solution since you run into a blocker for a cylinder shapes, arms aso. It is just easier to use edges contours in many cases. Best would be to let the user use both or either.
i'd like an automatic UV-packing tool that can do a good job of packing something, without being too wasteful. and i'd also like a way to group UVs, so that they're not packed into different locations, but are packed in relation as they were. example: you've UVmapped and mirrored the hands, and neatly placed them over…