SparseLaplaciansSolvers.from_meshes ERROR

[lihuashengmax]

Dear author, thank you for your excellent work!
When I try to run varients/deformations_MINIMAL.py, there is the error shown below. I think the mesh is normal, how can I fix the error? Thanks!

[lihuashengmax]

The error is related ro SparseLaplaciansSolvers.from_meshes, above is my setting.

[namanhd]

Would it be possible for you to send the mesh you're operating on?

This error (especially with pinning) means the mesh is probably bad in some way and needs to be preprocessed. The mesh has to be watertight manifold, and very thin triangles can also cause the laplacian matrix to fail at Cholesky decomposition. It's a bit unfortunate that this initialization can be very particular about the quality of the mesh; this is expected with any method that involves a linear solve with the laplacian.

My usual steps to deal with such meshes would be to open it in something like MeshLab and

1. Repair nonmanifold vertices and edges
2. Close holes if any
3. Isotropically remesh it (which gives uniform-aspect-ratio triangles, for better cotangent weights)

For difficult cases (such as meshes with many non-watertight disjoint parts, like many manmade objects from ShapeNet), before these steps you might have to also preprocess the mesh using something like Manifold or Manifold++ which are rather aggressive options that do turn every mesh into a watertight manifold one but at the cost of losing fidelity and losing any desired self-intersections. For most cases Manifold (at a high enough resolution) followed by an isotropic remesh to bring the resolution back down a little are sufficient and won't be too lossy.

Let me know if you have any trouble; you can send the mesh and I can try to investigate.

[namanhd]

@lihuashengmax bump

Do you still need help with this issue? Let me know if you've had better luck with other meshes or still need help with the one you were trying to use (do send it and I can look into it.)