Squishing mesh made from SubD, Bug?

When I try to squish a mesh, made from a SubD object, the squished copy is not selectable other then by window selection, and parts are not visible. Converting the subD into Nurbs before meshing solves the problem.

Hi - please post the 3dm file with the SubD object and instructions on how to reproduce this behavior.
-wim

After meshing the subD (directly or by QuadRemesh, and squishing the mesh (SplitSeams=Yes PreserveBoundary=No Deformation=Free Material=Floppy Outside=Up Decorate=No) parts of the squished mesh disappear while rotating the view, and selecting by clicking on the mesh mostly does not work. Window selection works fine. I just found out that after moving the mesh, the problem is gone. The same effects I see in V6, after exporting the Subd from WIP7 to V6.

SquishSubD problem.3dm (1.4 MB)

Thanks, this is filed as https://mcneel.myjetbrains.com/youtrack/issue/RH-58242 already.

I have been using ExtractControlPolygon on the SubD and then Unwrap followed by ExtractUVMesh. You might try that too depending on what you’re working on. It avoids this bug and I found the result was better for making a flattened version of the control polygon.

Ok, thanks for the reply.
Using your workaround means extra work,and how do you get the scale right for making 2Dpatterns that fit? Also flattening curves (or squishing back) on the surface is not included. But the result for flattening looks much better, no “scrambled edges” as Squish often produces for a lot of shapes.

I’d need to see more details on what you’re doing specifically to see if I could come up with a way. Make a new post just about that if you want me to take a look. At a guess, use Picture to bring in your source image and then snap to that when dragging out the UV Editor. I could be completely missing what you’re trying to do though. Maybe your goal is to flow objects along a SubD?

Hi Brian,

What I try to achieve is to make 2D patterns for the uppers of shoes, that fit on the (SubD) shoe-last after cutting the parts and stitching them together.
Therefore I need to make a mesh of the last (after splitting the last in two halves) to be able to squish the last and some curves on that 3d shoe-last.
Then I need to be able to squish back the curves that I have drawn on the 2D pattern.
I have experienced that Squish is not very reliable when it comes to the fit of the patterns, and for more complex (orthopaedic) lasts Squish is useless…

For now the only method to create 2D patterns is to produce the last (CNC or 3D print), make the flattening by hand, and scan the 2D “copie” to be able to draw the pattern curves in Rhino.
(Or use very expensive software like Shoemaster)
So any suggestion that can lead to a reliable flattening method is very welcome.

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Thanks, those details help in understanding. If I’ve got it right, you want to be able to take 2D curves and map them back to the SubD. I’d do this with Squish and SquishBack on a mesh created from the SubD as shown in this video and file I made.

Upper-Squish-Pattern.3dm (2.5 MB)

There are a few things I’d point out that will help in copying this workflow that I don’t show in the video. First, separate your SubD into parts using ExtractSrf and Join as needed. Crease the SubD verts that are on the ‘corners’ of the open edgeloops before the next step so that the edges meet up fully. Then use the Mesh command and the Simple Slider to make a mesh from the SubD halves. Join the SubD back together and run Squish on the meshes you made not splitting at the seams. You could also use Pull as a final step to make sure the SquishBack curves are exactly on the SubD.

I also didn’t show it but you could Squish some curves with the 3D mesh too if needed.

I hope this helps!

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Brian, do you think SquishBack with History could ever be possible?

Or failing that, a Grasshopper component using a script for example?

Squishback with history would be great, especially when squish would be a more reliable flattener for more complex curvatures.

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Thanks for the request… I filed https://mcneel.myjetbrains.com/youtrack/issue/RH-60261

It would yes. This has always been a massive limitation in the process to me. I did a search and there were a few threads about this, asking for something similar.

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