SubD: How do I get rid of these naked edges?

Building a simple shell by extruding edges in SubD box mode. Get to this point and cannot close the indicated naked edges between ceiling and walls. I must have missed the SubD 101 where this was covered - what do I do?

Stitch up.3dm (1.4 MB)

Hi Jeremy - I am not sure why it is this way but you can fix it by ExtractSrf the underside and the vertical edge faces, and rejoining these back into the rest.

image

-Pascal

Hi Pascal,

Thanks for the workaround. Thinking about why there is a problem: it might be because stitch doesn’t work for a pair of edges adjacent to a joined vertex. If I reduce the faces to this


I still can’t stitch A but I can stitch B. If I swap to smooth view and turn on control points there is obviously a difference between the corners, with a stitched vertex at one end:

An unstitch command would be helpful here…

In a separate test I placed two SubD planes together:


Having stitched 2, I cannot stitch 1 or 3, but I can stitch 4, further proof of my hypothesis.

Jeremy

Hi Jeremy - yes I see and in testing, it seems to me to be a bit finicky to even Stich edges that are on top of one another at all - is that your experience?

-Pascal

Yes absolutely, it can be deeply frustrating. But because I am new to this and experimenting to find the best way to do different things, I’m never sure to what extent I am struggling because I am approaching something in the wrong way or to what extent SubD isn’t ready for what I am trying to do (which in this case is different to what I see in @theoutside’s videos where he is riffing off SubD so creatively - I’m trying to produce models that conform to all sorts of dimensional constraints). Anyway, in respect of stitch, here are a couple more frustrations:

Post-selection needs to be more user-friendly: when you have to select the second edge it isn’t helpful to be presented with a list of edges including the edge selected first (without anything to say which is which).

Often after picking (I think) two edges I just get an error message telling me the count is wrong. That may be because I picked the same edge twice or because a vortex is being rolled up with the edges, or something completely different - to be user friendly the message needs to be more informative.

Jeremy

Right - that should not be allowed - I made this earlier:
RH-62027 Stitch: Edge selection tricky

-Pascal