GitLab

Summary: Fix #873, that grid_sizes defaults to the wrong dtype in points2volumes code, and mask doesn't have a proper default.

Reviewed By: nikhilaravi

Differential Revision: D31503545

fbshipit-source-id: fa32a1a6074fc7ac7bdb362edfb5e5839866a472

Summary:
Symmetric eigenvalues 3x3 implementation from https://github.com/fairinternal/denseposeslim/blob/roman_c3dpo/tools/functions.py#L612

based on https://en.wikipedia.org/wiki/Eigenvalue_algorithm#3.C3.973_matrices and https://www.geometrictools.com/Documentation/RobustEigenSymmetric3x3.pdf

Benchmarks show significant outperformance of symeig3x3 in comparison with torch implementations (torch.symeig and torch.linalg.eigh) on GPU (P100), especially for large batches: 70-280ns per sample vs 3400ns per sample for torch_linalg_eigh_1048576_cpu

It's worth mentioning that torch.linalg.eigh is still comparably fast for batches up to 8192 on CPU.

Some tests are still failing as the error thresholds need to be adjusted appropriately.

Reviewed By: patricklabatut

Differential Revision: D29915453

fbshipit-source-id: 7c1b062da631c57c4e22a42dd0027ea5e205f1b5