BUG: Duplicate control points after Fillet edge

Quite often I find out that certain fillet surfaces consist between 4 and 7 duplicate control points located at the very end. It only happens on certain radius size, whereas the majority of larger or smaller radii work just fine. In this example, the issue happens when the radius is 1 mm or slightly less than 1 mm. The video were captured last year, but I forgot to upload them at the time. Today that bug happened again while working with the latest Rhino 7 Service release candidate. The bug was also present in Rhino 5 and Rhino 6 over the past several years.

P.S.: I can’t upload the model, because it’s confidential work.

Hi Bobi - I’ll see if I can reproduce this. It wo8uld be interesting to know if ShrinkTrimmedSrf makes any difference in this behavior - I see the underlying surfaces are quite a bit larger than the trimmed faces when you are done, and I have see FilletEdge misbehave in the past in that situation.

FWIW, CreateSolid might save a good few steps in making that object to begin with.


I will have to try this with the model, though the bug also happens on relatively simple objects such like extruded curves that form a solid extrusion, which means that there are no split surfaces prior the fillet operation. The only workaround to this is to manually remove the unnecessary control points via the ! _RemoveControlPoint command, as I shown in my videos above.

Hi Bobi - RemoveKnot might also help but this should not happen as far as I know.


Hi Pascal, I found the model, but it’s already finished and tomorrow I may try to extract the basic surfaces and repeat the process to see if shrinking them will help to avoid the bug with duplicate points.

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