User strings not retained in SumSurfaces after JoinBreps

The subject occurs up through 6.0.18016.23451, 1/16/2018.

Before JoinBreps:
SumSurface bar
NurbsSurface bar
PlaneSurface bar
NurbsSurface bar
RevSurface bar
SumSurface bar

After JoinBreps:
SumSurface None
NurbsSurface bar
PlaneSurface bar
NurbsSurface bar
RevSurface bar
SumSurface None

UserStringsInSrfsAfterJoinBreps.py (891 Bytes)
VariousSrfTypes.3dm (69.1 KB)

Thank you,
Steve

Hi @spb,

Yep, I see that. Thanks for reporting.

https://mcneel.myjetbrains.com/youtrack/issue/RH-43931

– Dale

Hi @dale ,

I am having the similar issue when using Brep.DuplicateBrep().

Under Brep.Surfaces(), I have UserData saved in PlaneSurfaces, and SumSurface. But after DuplicateBrep(), all UserData under SumSurface are gone. PlaneSurface and NurbsSurface type are ok.

Geometries are simple extrusion to breps, not sure why it creates so many different types of surface.

I have been trapped on this for two days, finally identify it is because of this.
Please let me know if you need an example.

Thanks

Hi @mingo1214,

I’ve bumped the YouTrack issue.

– Dale

1 Like

A workaround for this is to convert each SumSurface to a NurbsSurface and copy the former’s user data into the latter before performing the Brep method. If the NurbsSurfaces (created and previously present) are unique, the SumSurfaces can even be retained after the operation.

Thanks, yes, I have converted all to PlaneSurface for fixing this problem.