Wish: SelNakedSubDEdges, DupVertex

It would be very useful to have some more _Sel commands for SubD.

Examples I’ve seen in other software are for naked edges and for creased edges. Internal uncreased edges would be great too. Another good one would be for holes (naked edges, excluding external border.) Why would we need holes when we already have naked edges? Convenience. There are a number of ways to sort holes from exterior naked edges, but some of them, like simply using the length, can fail: it’s possible to have a hole with a longer border curve than the exterior border of a SubD.



Maybe more? I’d also like to see these options on the SubDEdges grasshopper component.

Also: Adding _DupVertex command, history enabled, would be really useful. Either that or an option when selecting points in grasshopper to reference a vertex. What for? For example: creating planes from chosen subD vertices using the Plane 3pt command, using the planes to generate geometry for altering a Brep created from an editable subD.

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Thanks for the suggestions. I added https://mcneel.myjetbrains.com/youtrack/issue/RH-59189 and https://mcneel.myjetbrains.com/youtrack/issue/RH-59190 for the selection enhancements.

Regarding the request for a ‘dupvertex’ command. I want to make sure I file this one in the best way. It sounds like it might be useful for NURBS as well. Since the Control Point location on a SubD is what you’d need to line up to in order to Join two separate SubD, would it be better to have a DupControlPoint command with History support instead? I think you can also do this now in GH like this…

Provide a specific file and more details if you think we still need a new command. Thx

I’ll try this method and see if it works. The first difference I see, though is that with dupcontrolpoint with history, It’d just be more efficient. With this, I’d still need to import the points I want, and then use them to sort the vertices.

Seems like it’d be faster to have the option to just import history-enabled points to grasshopper or have grasshopper’s point component be capable of referencing vertices or control points.

For 100% generative design, this is less of a concern, but for combining explicit modeling with parametric augmentation, I think what I’m suggesting would be very helpful.

I filed https://mcneel.myjetbrains.com/youtrack/issue/RH-59197 . There may be a blocking issue that I’ve been lobbying for that would give control points their own ID number under the hood. Maybe it isn’t a barrier, but I mention it just to set expectations :slight_smile:

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Ah, this makes sense. Just like named selections, I’d expect it to fail on subD vertices if the subD has any faces, edges or vertices deleted.

But also, just like with named selection, that limitation doesn’t mean it would not still be very useful for deforming SubD objects after the user has committed to a topology structure.

I made some changes to the SubD Edges component. The Tag output now provides a richer description of the edge; it lists both the type (smooth vs. crease) and the topological kind (naked vs. interior vs. non-manifold).

However in order to prevent this change from breaking existing files, this new output is only available if you create a SubD Edges component anew. If one is opened from an older file, it will behave as it used to before.

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