Playing with SubD. Can someone explain these? Display, Snaps, split?

I was following a YT “simple cup” tutorial on SubD. I wanted to see how adding a vertex on a particular face would affect the look. I couldn’t find where/if this was possible. Further the only snap that worked was Vertex. Also, the tutorial uses 3DFace to make faces and the become transparent when the model is rotated. Why is this? I find it confuses.

In the most recent version of the WIP, some more snaps work, but not all. Mid snap, for example, works in smooth mode.

It’s a very early version, they seem to be working through adding missing features slowly and steadily, in part based on user feedback.

Insert edge will let you split that mesh face that you’ve pointed out. Inserting a single point on the top of your dotted line to make it a single pentagonal face and also do the same to the face above it: not a working feature yet, but _insertpoint seems to be on the list of commands they’re developing.

Current workaround to insert that single point: do the insertedge command, then delete the two resulting faces and draw a single subd face using the vertices around the hole you just made as points, and selecting “no” on the interpolate option on the single subd face command. Works in flat mode, not always in smooth mode.

Thanks for the response, but I’m not understanding this and not getting usable results. Is it possible to show the method? I’ve attached the file. Also, what/where is smooth mode?

cup.3dm (36.0 KB)

Moved to Serengeti > SubD

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Your model was a mesh still so you would have to use UnifyMeshNormals to fix the faces you added that had the normals facing inward. Then use ToSubD to make a SubD surface from the mesh. InsertPoint is the command you were looking for to insert a vertex / edge. This doesn’t work on SubD surfaces yet… but it’s filed as RH-53954

Once you have a SubD, use the Tab key to toggle the display mode.

The cup in file you sent is a mesh.

If you don’t have the latest version of the WIP, download and install, or some of what I’m saying below won’t work.

The first thing you need to do is select the cup and call the ToSubD command, and select the option to delete input.

Then type: SubDDisplayToggle (I believe the latest WIP assigns this command to the F4 key, I’ve assigned it elsewhere on my machine because I use F4 for Ortho toggle)

Then try playing with the InsertEdge command. Call it, click on an edge of a face, and see what it does, try it with different options.

Also try selecting edges and deleting them to see what happens.

This will probably be a useful link: https://docs.mcneel.com/rhino/7/help/en-us/toolbarmap/subd_toolbar.htm

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tosubd worked fine for me without running unifymeshnormals, FYI.

That makes sense, the SubD surface can’t to my knowledge have flipped normals per face but a mesh can… hence that command. Good point about using InsertEdge, I am personally hoping InsertPoint gets added for the release as it will be a bit more flexible I think in terms of where you can add an edge. It works on meshes now.

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I guess I did not explain myself correctly. I was trying to alter the mesh before using the “ToSubD” command. I did not like the output I got from the command, and thought if I was able to edit/change the Mesh, (add more vertices) before converting to SubD I would get a more pleasing output. Am I wrong about that? Is it preferable to work on the object after conversion?
I am using the latest WIP. I’ll try your suggestions.

Depends on whether you’re good with mesh and can anticipate the results.

One way to work with it as a mesh while seeing results in SubD would be to use grasshopper to move the mesh a little ways over, and then use the mesh to subD component. Then you could see SubD results from mesh changes in real time.

I’m not an expert on mesh. I don’t like the instant results from converting to SubD here either, but I’ve been practicing using the subD tools to get what I want. When I took a look at the SubD results, for what it’s worth, I got more improvement from deleting extraneous edges than from adding anything.

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