Curve Control Points cannot be deleted without deleting the whole curve

I recently started using Rhino 7 WIP for Mac, and this very basic procedure does not work properly.

  1. select a Nurbs curve
  2. turn control points ON
  3. delete some points in the middle of the curve
  4. the whole curve is deleted

Am I doing something wrong, and I should use slightly different commands, or is this a bug?
Thanks for letting me know


I can not duplicate that.
I drew a single span degree 3 curve with 4 points.
Turned on the points, selected an interior point and deleted it.
The curve changed shape and had 3 points.
I selected the last interior point and deleted it.
Now the curve is straight with just end points.

What are you doing differently?

I have noticed it too. It is not regular behaviour and does not have a pattern.
It happend for me several times, last one with curves created with Elk plugin from GH.
Example file attached, See crv marked with Revision Cloud.OSM.3dm (1.0 MB)

That’s a degree 1 polycurve, but it acts the same way.
If I select the polycurve and run PON, then I can select the inline control points between sharp angles and delete them.
If I select a point on a kink, it changes the shape of the polycurve.

Is there any change you are selecting the curve itself (not points) and tapping Delete?
Then it would act just like you described.


  • clicking on a curve thus activating a control points and
  • running _PointsOn command and then deleting any point results in disappearing the curve

What build of V7 WIP are you running?

Last one before today’s.

Chek this out: remove one control point of a revision cloud and the whole thing goes away.

Wow: Just installed today’s build and the problem went away.

Something must have been fixed that has not been on my radar.
It seems fine in both Windows and Mac

RevCloud points too

I checked polyline and rev cloud too. Both works as expected.