Dendro, is that you?
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Hallelujah!! This is what I need! Thank you Rhino developers!
I work a lot with mesh data and sometimes the mesh is just bad; instead of trying to fix the mesh, shrinkwrap is usually the faster and better option.
I just tested it on a mesh in which I had a lot of duplicates that I struggled to remove and it worked like a charm. Now I have one decent mesh. Thanks a million!
Can you also put it in Grasshopper please?!
You’re the best!
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I’m not certain that shrink wrap is the right tool for this task for the simple fact that shrink wrap will always result in a closed mesh vs any form of mesh plane. It seems like some form of mesh drape with boundaries and internal hole filling would be more suited for the task. Certainly something we can keep in mind as we tackle some of these more complicated remeshing tasks.
some kind of mesh drape like that sounds great.
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Hi,
first - thank you for interesting new tool. Looks very promising. 
My first test object is a seat cushion of a train seat. I don’t want to increase the size, but without an offset I don’t get a closed object. Could be nice, if the scattered look could be avoided.
Here I used an offset, the surface is closed but the size is much to large. I expected a result where the whole object looks like in a shrink wrap foil. I miss to define a hole size which makes inner holes closed.
I expected a result which looks like if I would take a kitchen foil and wrap around. A single surface option could be nice so that it looks like known from QuadRemesh.
Hi @Micha
One way you can use now to fill in openings without making the object larger is to shrinkwrap once with a large positive offset, then shrinkwrap that result with a negative offset of the same magnitude
(like the process described here How to smooth a curve but preserve area? - #2 by DanielPiker)
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What type of offset? Negative offset in the Shrinkwrap dialogue box? Or just a typical mesh offset?
Shrinkwrap with offset r, then shrinkwrap the result of that with offset -r (in the shrinkwrap dialog box)
This gives you a solid like you’d get if you tried to mill the shape with a spherical bit of radius r.
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Will be possible to ShrinkWrap a positive+negative mesh?
(do a Boolean subtraction without first using the _MeshBooleanDifference command)
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More volume style tools are on the roadmap.
Please try the new mesh booleans in v8 and report any issues you have here.
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Hi there, The ShrinkWrap tool looks like an exciting addition but I’m having an issue getting it to work, every time I trial ShrinkWrap I get the message ‘ShrinkWrap failed to generate a mesh’. I have an 8 year old macbook pro running MacOS Big Sur 11.7.1 Could the issue be with my older mac?
Any help would be greatly appreciated.
Share your file and system info on a separate thread. So we can help you.
I had really wished ShrinkWrap could produce an acceptable result with this the type of object in the file below. Even if I set the edge length target very fine, it cannot produce sharp edges, they are always jagged and “bitten-off”…
TestAFewBldgsMM-SW.zip (6.4 MB)
This (want to eliminate the overhangs):
Becomes this (settings edge length 0.05mm, unwelded afterwards):
When Magics first introduced Shrinkwrap for fixing 3D printing objects maybe 15 years ago, it produced the same kinds of artifacts…
the more important question is even with this, does your printer even care?
I’d be curious to see some test prints to see if any of what you are seeing translates to actual physical flaws in your part.
In my experience, stuff that look like that on screen typically prints fine, and even if there are some small defects in the print, by the time they get cleaned up, or primed, painted, etc… these flaws are a non issue.
Even for tooling, this stuff tends to get polished out.
But your mileage may vary from mine. 
Yes, it does, the defects are on the order of the max edge length setting, so in this case around 0.05mm. A good quality 3D printer (polymer inkjet, sla) picks this stuff up no problem. Of course, I could set the threshold even lower, but my experience is that it simply hangs Rhino. Already one small building had over 60K faces because everything is subdivided, not just the edges. That’s mostly unworkable if there are a large number of objects. MergeAllCoplanarFaces does not work to reduce that - all it creates is NGons, it does not actually “merge” any faces…
These objects generally don’t get individually sanded - when there are hundreds of them they might get a light sandblasting, but that does not fix the defects/softness at the edges. Painting only adds more edge softness, so the idea is to have as much sharpness as possible to begin with.
standard layer resolution for most DLP’s is going to be around .025 mm in Z thickness and around .05 mm YX resolution. You’ll see more Z layers on this part than you will double contouring side effects. SLA generally maxes out in spot diameter around .05 so it’s a non event. FDM will definitely never show any of this at these resolutions. If anything 1 or 2 smoother iterations could be helpful here if it doesn’t cause too much shrink. Daniels been working with some Implicits that might be helpful in these sorts of scenarios but SDF is always going to result in these sorts of artifacts to some degree.
Well, we can agree to disagree… If the result of Shrinkwrap leaves, say a 0.05 chamfered corner, then the slicing will reflect that and the toolpath will follow the chamfered slicing contour. The result is this:
The red line is the slice polyline, the blue circles represent a 0.05 diameter ‘spot’ that follows the toolpath. The “sharp” corner has the theoretical radius of the spot (0.025), whereas the chamfered corner is flattened off and has a sort of “visual” radius of around 0.06.
Yes, we can certainly make the target edge length smaller still, but the amount of mesh faces required goes up exponentially, and the whole thing blows up memory and processing wise…
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Did you print it yet to verify you can see it? Have you also adjusted the polygon optimization and smoothing values at all?
Smooth 3 , poly optimize 50%
The Z slice will be far more noticeable than any of the contouring.
I’m curious now. Can I have the file please? I’ll print it here on the 8K Elegoo Saturn 2 at 3 micron and we’ll settle this.
G
its posted above. The saturns max XY resolution is 28.5 microns. So id say wrap it at .02 to .025 mm.