SubD "Merge edges" and "Bridge"?

I just watched a video about Rhino 7’s SubD and I noticed one common case that also happens quite often with 3DS Max polygon modeling. Check this video at the 3:02 minute where the focus is on a bunch of corner faces that are basically where the control polygon has a 90-degree transition:

I wonder is there a tool in SubD that could merge edges to other adjacent edges, so that this particular model gets transformed into the following shape? Also, is there a “Bridge” tool between faces in SubD already? :slight_smile: At 7:05 minute of the video I saw that there is a “Bridge” between holes, though. Will the faces need to be deleted in order for the “Bridge” tool to work?



Hello - DissolveEdge does something like what you describe but the result is not as in your diagram, using that setup as input.


Bridge does look for naked edges.


I see the lack of a proper “Merge edge” as a big miss for SubD, because that technique is widely used in most 3d mesh modeling programs to deal with 90-degree shapes that must be transformed into a more useful transition while preserving the main structure. The video above shows a typical problem when trying to smooth out the model in that area. Merging the edges is the way to solve that oddly looking transition.

3DS Max also has a “Target weld” command that allows the modeler to pick a control point and merge it into another adjacent point. Merging two points to adjacent points does the same result as “Merge edge”.

Well, I don’t know, SubD has not been my bailiwick, particularly, but your diagram seems to assume some unexplained (to me) magic at the vertical edges adjacent to 1 and 2.


It’s fairly easy to explain the process of merging edges. First mouse click is on the red edge marked with 1. Then the second click is on the next edge where the arrow points. That will result in what the middle figure shows.
The third figure shows what happens if the command is repeated with the other red edge marked with 2. 3d mesh modeling programs based on the Catmull-Clark subdivision principle do it with ease.

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Work with the Stitch command But now there is a problem and I have reported it

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