pytorch3d/tests/test_laplacian_matrices.py
Tim Hatch 34bbb3ad32 apply import merging for fbcode/vision/fair (2 of 2)
Summary:
Applies new import merging and sorting from µsort v1.0.

When merging imports, µsort will make a best-effort to move associated
comments to match merged elements, but there are known limitations due to
the diynamic nature of Python and developer tooling. These changes should
not produce any dangerous runtime changes, but may require touch-ups to
satisfy linters and other tooling.

Note that µsort uses case-insensitive, lexicographical sorting, which
results in a different ordering compared to isort. This provides a more
consistent sorting order, matching the case-insensitive order used when
sorting import statements by module name, and ensures that "frog", "FROG",
and "Frog" always sort next to each other.

For details on µsort's sorting and merging semantics, see the user guide:
https://usort.readthedocs.io/en/stable/guide.html#sorting

Reviewed By: bottler

Differential Revision: D35553814

fbshipit-source-id: be49bdb6a4c25264ff8d4db3a601f18736d17be1
2022-04-13 06:51:33 -07:00

120 lines
3.8 KiB
Python

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the BSD-style license found in the
# LICENSE file in the root directory of this source tree.
import unittest
import torch
from common_testing import get_random_cuda_device, TestCaseMixin
from pytorch3d.ops import cot_laplacian, laplacian, norm_laplacian
from pytorch3d.structures.meshes import Meshes
class TestLaplacianMatrices(TestCaseMixin, unittest.TestCase):
def setUp(self) -> None:
super().setUp()
torch.manual_seed(1)
def init_mesh(self) -> Meshes:
V, F = 32, 64
device = get_random_cuda_device()
# random vertices
verts = torch.rand((V, 3), dtype=torch.float32, device=device)
# random valid faces (no self circles, e.g. (v0, v0, v1))
faces = torch.stack([torch.randperm(V) for f in range(F)], dim=0)[:, :3]
faces = faces.to(device=device)
return Meshes(verts=[verts], faces=[faces])
def test_laplacian(self):
mesh = self.init_mesh()
verts = mesh.verts_packed()
edges = mesh.edges_packed()
V, E = verts.shape[0], edges.shape[0]
L = laplacian(verts, edges)
Lnaive = torch.zeros((V, V), dtype=torch.float32, device=verts.device)
for e in range(E):
e0, e1 = edges[e]
Lnaive[e0, e1] = 1
# symetric
Lnaive[e1, e0] = 1
deg = Lnaive.sum(1).view(-1, 1)
deg[deg > 0] = 1.0 / deg[deg > 0]
Lnaive = Lnaive * deg
diag = torch.eye(V, dtype=torch.float32, device=mesh.device)
Lnaive.masked_fill_(diag > 0, -1)
self.assertClose(L.to_dense(), Lnaive)
def test_cot_laplacian(self):
mesh = self.init_mesh()
verts = mesh.verts_packed()
faces = mesh.faces_packed()
V = verts.shape[0]
eps = 1e-12
L, inv_areas = cot_laplacian(verts, faces, eps=eps)
Lnaive = torch.zeros((V, V), dtype=torch.float32, device=verts.device)
inv_areas_naive = torch.zeros((V, 1), dtype=torch.float32, device=verts.device)
for f in faces:
v0 = verts[f[0], :]
v1 = verts[f[1], :]
v2 = verts[f[2], :]
A = (v1 - v2).norm()
B = (v0 - v2).norm()
C = (v0 - v1).norm()
s = 0.5 * (A + B + C)
face_area = (s * (s - A) * (s - B) * (s - C)).clamp_(min=1e-12).sqrt()
inv_areas_naive[f[0]] += face_area
inv_areas_naive[f[1]] += face_area
inv_areas_naive[f[2]] += face_area
A2, B2, C2 = A * A, B * B, C * C
cota = (B2 + C2 - A2) / face_area / 4.0
cotb = (A2 + C2 - B2) / face_area / 4.0
cotc = (A2 + B2 - C2) / face_area / 4.0
Lnaive[f[1], f[2]] += cota
Lnaive[f[2], f[0]] += cotb
Lnaive[f[0], f[1]] += cotc
# symetric
Lnaive[f[2], f[1]] += cota
Lnaive[f[0], f[2]] += cotb
Lnaive[f[1], f[0]] += cotc
idx = inv_areas_naive > 0
inv_areas_naive[idx] = 1.0 / inv_areas_naive[idx]
self.assertClose(inv_areas, inv_areas_naive)
self.assertClose(L.to_dense(), Lnaive)
def test_norm_laplacian(self):
mesh = self.init_mesh()
verts = mesh.verts_packed()
edges = mesh.edges_packed()
V, E = verts.shape[0], edges.shape[0]
eps = 1e-12
L = norm_laplacian(verts, edges, eps=eps)
Lnaive = torch.zeros((V, V), dtype=torch.float32, device=verts.device)
for e in range(E):
e0, e1 = edges[e]
v0 = verts[e0]
v1 = verts[e1]
w01 = 1.0 / ((v0 - v1).norm() + eps)
Lnaive[e0, e1] += w01
Lnaive[e1, e0] += w01
self.assertClose(L.to_dense(), Lnaive)