Without this line, the resulting shape will be at the plane, parallel to XY-plane.
The idea is, using a quaternion, put points to a plane, parallel to XY-plane, build a shape and a geometry of THREE.ShapeGeometry()
and apply original points, as we have a set of faces, we just use old points instead of current ones in the geometry.
There are UVs for the shape from the fiddle:
And there’s no surprise why: