Voronoi fracture results in poor quality geo

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Hi,
I am using the voronoi split/fracture node on the default test pig head and finding that whatever settings I use I get a poor quality resulting surface. It has holes all over the place where the split faces don't properly sit together.
How to I stop this happening?
Here's what I am seeing:


Bonus question - is it possible to do a voronoi split without actually separating the pieces? ie the result I would get if I used a fuse after running voronoi split (without internal surfaces). I don't want to rely on fuse because I might fuse points that shouldn't be fused.

Thanks!

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piggyWithHoles.JPG (143.9 KB)

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please post the scene and freeze the voronoi fracture sop.
this should not be happening.

greetings

Olaf
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Here it is, hope you can work out what is going on!

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holeyPigHeadTest.hipnc (1.4 MB)

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That was using v 17 non-commercial but I also tested 16.5 commercial version and it behaves in the same way.
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Looks to me like the voronoi split node can't handle non-planner faces.
Pre-triangulating would be a workaround in some cases but it will mess up others and it would be great if it worked robustly for all good faces.
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sorry i did not answer yet. I will try to look at it later
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yes you are right this is not a clean solution.
But you could use the divide sop before voronoi fracture
- turn off or set Maximum Edges to 4
- turn on triangulate non planar, so the planar quads will not be divided.
this would result in what i would expect. It keeps the good planar faces…

BUt it still has errors… grr

greetings

Olaf
Edited by Olaf Finkbeiner - Nov. 5, 2018 16:32:38
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PS
the pighead has almost no planar faces
setting the Non-planar polygons value to a small value will not leave many faces untriangulated.
So voronoi fracture actually does quite a good job…
for the pighead i get almost 100% non planar at 0.001
for a torus i get 0% at 0.000001
Edited by Olaf Finkbeiner - Nov. 5, 2018 16:44:02
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Yes the pig head is a great test model as it's so lacking in planner faces!
The workaround splitting the faces first does seem to work fairly well but it would be nice to have a more robust solution out of the box.
Thanks,
Philip
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The pig head is a subd model, so it should be subdivided to the limit surface and triangulated before fracturing.
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