This occurs in V5 - V7.11: Directly deleting entire rows of control points from a non-rational surface converts it to rational even though _List reports all weights as 1.

Yeah, I’ve encountered this before, from a different cause though - I can’t remember the reason, I asked at the time but… let me ask again… RH-66021 Removing surface control points makes it rational -Pascal

https://mcneel.myjetbrains.com/youtrack/issue/RH-61777 was about _RemoveKnot creating rational curves, but not surfaces. Directly deleting control points makes surfaces rational, but not curves.

I’m seeing this in Rhino 7 Crystal Vape - Rational Srf.3dm (5.9 MB) ▶ System Info

Hello- this was fixed in 8. -Pascal

Removing CPs makes surface rational

Rhino

brian (Brian Gillespie) October 26, 2021, 10:52pm 4

RH-66021 is fixed in the latest WIP

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Removing CPs makes surface rational

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