Mesh gradient editor: artefacts

[B-Vs-V]

Here is what I get when I setup a mesh gradient (via first the Mesh gradient editor tool):

[b77]

@Pat I guess this is a control point that was dragged outside it's area and past another control point, over the other side, creating a sort of "fold".
But it can always help if you post the file here.

[VectorStyler]

@Pat Yes, this can happen. I will try to improve this.
Some of these self-overlapping cases are a bit difficult.
For example, if a control (tangent) point is rotated too much, it may create some impossible cases.