Unwrapping a custom ShapeBufferGeometry

Hi, I’m trying to use a shader to get an inset border in some custom geometries, but it turns out to be a big task for me.

Not sure if I’m not implementing the effect correctly or maybe the custom shapes need to be unwrapped in a specific way (or both).

This is my post in StackOverflow: three.js - ThreeJS: Problem implementing 'non-ThreeJS' shader - Stack Overflow

Are the custom shapes’ UVs automatically unwrapped after being created or they need an specific unwrapping for ellipses, triangles, etc.?

If they are not unwrapped, it would be nice to have some unwrapping methods in some ‘utils’ class for noobs like me. Thanks for all your work on this engine.

As far as I know, shape UVs are world coordinates.

If it’s of any help, I once wrote some shaders for different types of shape “vector” gradients, including “contour” gradient, that could be used to create borders, after some modification.