Shrink problem about the splited surface

I splited the surface with a curve. After that, I wanted to shrink control points around it. But I couldn’t shrink them. Because the shrink was already done. So I tried to solve this problem using ShrinkTrimmedSrfToEdge even though. But I couldn’t do that. How can I do now ?
436-2-질문.3dm (2.2 MB)

That is the expected result- shrinking will only remove all of the extra control points if the trim is an isocurve. Arbitrary trims will always leave some points, since the full grid of points must be maintained in each direction throughout the underlying surface.


Thank you Pascal.
I tried to drape a design pattern on the surface using “ApplyCrv”. In that case, but I couldn’t control to put my pattern in the exact boundary of splited area.
So how can I delete the extra control points above the boundary ?

Hi hylee- I guess I would make the 2d pattern in the uv rectangle from CreateUVCrv - then you will see where the trim curves lie in the 2d space.


I did that, but I couldn’t do it like below image. I think my problem is to remove extra CPs around this splited surface. I think "split command’ cannot remove extra CPs but I don’t know the reason why. There were no commands at all to solve it, I guess. Thanks Pascal.

See the section on NURBS surface topology in


Thanks a lot Pascal.

If I can solve this one, I’ll show the process immediately.