@davidcockey: Yes, that’s the case I’m thinking about (the extracted edge-curves I’m referring to in the header although I didn’t say that).
So, in effect, it is the control points of a surface I want to modify (based on the structure of the extracted boundary curves) in order to arrive at an “untrimmed” surface where the isocurves are not aligned with the edges, right?
Edit: If so, are the
Edit Points (of the curves) and the
Control Points of the surfaces “compatible” so that aligning the surface edges with the curves (and evening out the CPs in between end points) would always result in the same edge positions?
Edit: The problem I describe above illustrated :
It’s obvious from the picture (at “A” and “B”) that
DuplicateEdge, for instance, doesn’t result in curves that reflects the surface’ structure at the edges. The degree is preserved in the curve(s), but not the edit point structure.
At detail “4” I drew (black) interpolate curves through the surface’ control points, and then comparing the curves and the surface’ structure at 6:B shows that interpolate curves are not a big help in constructing a structure to which the trimmed surface (from “3”) can be reduced (or “shrinked”) into an untrimmed surface.