My understanding (via the help) is that editing a curves controlpoints will discard any user text set to the geometry via
rhinoscriptsyntax.SetUserText (object_id, key, value=None, attach_to_geometry=True)
However it seems editing cp’s will not discard user text set to geometry, where for instance deleting cp’s will.
I also found this related and unanswered post:
Deleting the user text (or any user data for that matter) upon CP editing is a BUG.
My understanding is that there are 2 types of user text:
one bound to geometry and one to the object.
The help here make me come to that conclusion:
I think this bug is thus (somewhat) unrelated.
@dale can you shed some light on this?
In general, Rhino tries to maintain user data. If you find a situation where it is not retaining user data, then let us know.
@Willem, the comments you highlighted might have applied to V4.
Thanks for the info. The image I pasted is from the python help in V5 so @stevebaer might want to update that method and it’s help/description.
It does leave me with a follow up question:
how to know via python, if cpoints are edited.
There is nothing in the Rhino SDK that will let you know something has been modified via control point editing. But by tracking an object’s runtime serial number, you can at least tell when the object has been modified.