Studio parts editor, decals, connectivity...

[Philippe Hurbain]

I don't know exactly. Looks like some form of u-v mapping (hence the added parameters to type 3 triangles in textured Studio parts). But in most cases (in particular minifig heads and torsos) it shouldn't be very difficult to convert from one format to the other. Remains the issue of ownership of images in the case of Studio to  LDraw conversion.

Definitely u-v mapping.This kind of explain the choice of a different method than LDraw texmap, since this method is more powerful (but imho overkill!)
I inserted a regular grid pattern, replacing a standard face decal, and here is the result in Studio. If it was simple cylindrical mapping, the top and bottom lines wouldn't appear there. Note the strange wiggles of lines that should be straight...