Hello - run MakeUniform on these - you’ll see the isocurves even out, for one thing. Mr Pink has a fully multiple knot at the top end of the curved part, which Mr Green does not - that makes the isocurves appear different, and introduces a kink at that location.
If I remember correctly the difference between uniform and non-uniform (or at least one of the differences) was that the weight of the control points in one of the are all 1s and the points are 3d whilst the other are 4d and you can modify the weight.
Is there some way in Rhino that these are shown as being different? Because currently in Object Description I see no difference.
Hello - all weights are 1 here as far as I can see. The difference is in the knot vector. Use UntrimAll and then List to see the knots (among other things) - you’ll see one in the pink surface that has a knot of multiplicity 3 that is not at one end of the list. That is the kink.
I do not know that term, but that does not mean much… my guess of the moment is that it is a 3d thing - a locally highest point or series of points on a surface- something like that. I do not know if it applies to surfaces as NURBS things or 3d topography, so to speak…