Hey everyone, I would like to create the following setup for a box: [image] In which a unique label or identifier can be tied to every face as such and have it persist through non-destructive transformations (rotation, translation or scaling).: 1 - Bottom; 2 - Top; 3->6 - Sides A specific face…

I’m looking for the same thing. My use case: I need to boolean several objects into one, and then do a remesh operation, with the resolution of the faces determined by the objects original ‘parent’ solids.

I think the most simpel but a bit brute force approach is to create a very rough mesh per face and use the inner vertices as sample points against the parents. Note that also geometry can hold custom data / user strings but it is not clear / documented when this data survives or gets lost for examp…

Thank you @Tom_P ! I did try setting userText (in gh) for brep faces, but that info is indeed lost as soon as you join them back into a solid. I will have to stare at your mesh idea for a while longer before it sinks in :wink:

[image] Declan Halpin: brep faces Did you try to attach it to the underlying surface? https://developer.rhino3d.com/api/rhinocommon/rhino.geometry.brep/surfaces EDIT: @declan i did a fast test and it looks like attaching user Data to the underlaying surfaces survives boolean operations an…

Interesting. Are you accessing the srfs in Rhino or gh? Would you mind sharing your test? Using vanilla gh: [image] Using gh python to access Rhino.Geometry.Brep class: [image]

[image] Declan Halpin: accessing the srfs in Rhino or gh in a command in a rhinocommon / c# plugin - using above link / Rhinocommon function. my guess - vanilla gh does not access user Strings attached to geometry (only to attributes).

Just doubling back here because I saw this Material workaround mentioned in another thread. [image] Struggling with GH Definitions – Design Principles or Best Practices? Grasshopper Any favorite strategies or rules of thumb on how people select geometry? FWIW: I’m a big…

Persistent sub-object identifiers

Rhino Developer

declan (Declan Halpin) April 29, 2025, 8:16pm 8

Just doubling back here because I saw this Material workaround mentioned in another thread.

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Persistent sub-object identifiers

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