Reduce surface complexity changing spans and degree

Hi, how can I reduce the surface shown to a degree 5/5 single span surface? The Rebuild command destroys the CV structure also in the direction where degree and CP count was not changed by me. Thanks!

Reducing surface complexity.3dm (221.9 KB)

Hello- RemoveKnot is where I’d start if you want to simplify it. The U direction has several internal knots - you can get rid of those and then ChangeDegree in U to 5 to get some more points back if needed.


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Thanks Pascal, very helpful.

I set the Isocurve Density to 0 to see only real knot lines. Then I clicked on the two knot lines in the V orientation, and only 4 CPs were left in that direction. Then I changed the degree in the V orientation back to 5 and thus I have 6 evenly spaced CPs. Then I matched both sides G2. When I then join the surface with its right hand neighbour, and check for naked edges, none is shown along their common boundary. So, I would think this is the way to do it to always have clean single span surfaces.

Is there a way to check numerically if the surfaces are G2 continuous, other than relying on the Zebra display? It looks good, but I’d like to know for sure…

Hello - use EdgeContinuity to check.


Shows 0.000 (-1.000) for G2. I assume that means… within the set tolerances. Is EdgeContinuity also available in the Rino 6 release?

Nope - that is a V7 feature.


I see. In any case, the issue is solved. No more multi-span surfaces with your two-step process. Very good!