SubD friendly curve after a point added does not extrude into a SubD

Rhino SubD
1

Hello,
As the title says, a SubD friendly curve after a point added does not extrude into a SubD

Is this the way it should be as it can be confusing ?

Cheers
Joao

2

Hi Joao -

The title doesn’t actually specify all the assumptions that you are making, but anyway…

I’m sure it can be confusing, but, yes, this is by design.
When you edit a curve that was created with the SubDFriendly=Yes option, it gets demoted from “SubD friendly+” to “SubD friendly”.

Only curves that are “SubD friendly+” will automatically create SubD objects when extruding with the gumball.

Note:

  • You can turn a “SubD friendly” curve into a “SubD friendly+” with the MakeSubDFriendly or Rebuild commands
  • You can always force the creation of SubD objects, even from “unfriendly” curves, by using the ExtrudeCrv command and setting the Output option to SubD.

Further reading - RH-58784
-wim

3

Thank you for the detailed explanation Wim
Joao