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Yixin-Hu / TetWild

Robust Tetrahedral Meshing in the Wild.
https://yixin-hu.github.io/tetwild.pdf
GNU General Public License v3.0
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TetWild creates invalid surface connectivities. #41

Open nburgess350 opened 5 years ago

nburgess350 commented 5 years ago

Hi, I was recently using TetWild to do some re-meshing before some finite-element simulations. When generating a particularly coarse mesh with --epsilon = 500, I got a mesh that has 4 boundary faces incident on the same edge (see attached picture). Using a higher value of epsilon seems to make this go away but I thought you might want to know.
badtetwild

Best Regards and Thanks, Nick

qnzhou commented 5 years ago

Thanks Nick! Does this happen at a particular thin feature of the input?

jdumas commented 5 years ago

I don't think there is anything in TetWild's algorithm that prevents it from creating non-manifold edges. I mean, if the envelope is too large, and surface vertices get pinched into a single edge within the envelope, the result is still technically correct (and I don't think there is any topological check in TetWild's update scheme). Decreasing the epsilon should make it go away as you observed.

Yixin-Hu commented 5 years ago

Jeremie is correct. Large envelope would make the output "pixelized".