RBD Material Fracture Wood Issue

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Hi there,

I have just started messing around with the RBD Material Fracture to fracture a wooden structure, and I am getting these very odd extra geometry both in the 1st output and the proxy geometry output (It seems like the geometry used to make the splinters).

I am just wondering if this is a bug or did I not setup the geometry correctly before the fracturing?

Thanks in advance.
Edited by erhardiazz - May 29, 2019 22:18:49

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rbdMaterialIssue.hipnc (652.5 KB)
screenCaptureIssue.PNG (1.5 MB)

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I tried your file… however the locked Object Merge sop comes in with no geo so the boolean does nothing. (Maybe try a stash SOP instead?)

When I ran it through the RBD MF node, it worked fine though. I did put a clean node just before it though to remove all the attributes, but even without this it worked.

I have found with booleans though that sometimes you get extrusions or surfaces that are not manifold, (water-tight). So it might help to put a polyfill on just to make sure all non-manifold geo is capped.
Sean Lewkiw
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Hi, thanks for replying and also the tips on booleans.

I have a revised version, with the stash sop and clean sop and polyfill sops, but it still seems to give me the same error.
I am almost certain now that the extra geometry is the splinter cutting planes.

Again, any help or tips will be greatly appreciated.
Thanks in advance.

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rbdMaterialIssue_2.hipnc (692.1 KB)

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Hi, I added a polycap and a fuse and it works now. It is also a lot faster. I have also put a divide SOP in there which sometimes helps if the above does not, (it is bypassed but you can see what it's doing).

I often use the blast/exploded view workflow to isolate troubling bits to help debug. When exploded, you could clearly see some of your booleans were uncapped. One problem will be that those extra polys added by the boolean will not have a name attribute if you have pre-calculated names, (but in your case you have not).

Sean

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rbdMaterialIssue_3.hipnc (718.7 KB)

Sean Lewkiw
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Hi, I have done everything as mentioned above but still no success.. mesh is also fine as PolyFill is giving a warning mentioning that there is nothing to fill. Earhardiaz is right about those extra geometries to be splinter cutting planes.
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I had the same kind of problems, for me it comes from a ‘clean’ SOP, with manyfold-only topology checked. Unchecking this seems to solve the problem.

Cheers

Yann
Cheers,

Yann

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I find the following often helps, (try one or more in various combinations):

  • reverse sop
  • divide sop to bricker
  • divide sop to triangulate after bricker
  • polycap
  • fuse
  • clean (as described above post)
  • in the RBD Material fracture node, toggle: Detail -> detriangulate -> only unchanged polys
Sean Lewkiw
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Hi, I was wondering if anymore insight has gained regarding this matter. I’ve tried all of the above but can’t get rid of the splinter geometry.
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Fwiw, I was having the same problem and Sean's suggestion of Detail -> detriangulate -> only unchanged polys worked a treat.
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Just a quick shout out to MrCatfish for their suggestions on this issue. While they did not work perfectly, they got me a most of the way there for resolving these types of issues. I was inspired to make myself a simple little asset to "pre-process" incoming geometry for RBD material fracturing so I don't have to keep dealing with this headache going forward. For the most part it works for most issues that may exist on the incoming geometry which is a big relief.

I didn't share the asset because honestly it's really not that hard to make on your own and it's good practice for you anyway. Ultimately, it addresses most of the major issues that will cause headaches going into the fracture process. Thought I'd share just to motivate others to do the same for yourselves.

Thanks again to all you wizards out there.

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Screenshot 09-24-2021 14.34.55.jpg (208.1 KB)

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