Fix save_ply with noncontiguous faces

Summary: As noted in #710, save_ply was failing with some values of the faces tensor. It was assuming the faces were contiguous in using view() to change them. Here we avoid doing that.

Reviewed By: patricklabatut

Differential Revision: D29159655

fbshipit-source-id: 47214a7ce915bab8d81f109c2b97cde464fd57d8
This commit is contained in:
Jeremy Reizenstein 2021-06-21 06:05:03 -07:00 committed by Facebook GitHub Bot
parent 8006842f2a
commit 354a1808ff
2 changed files with 13 additions and 3 deletions

View File

@ -1154,9 +1154,14 @@ def _save_ply(
if ascii:
np.savetxt(f, faces_array, "3 %d %d %d")
else:
# rows are 13 bytes: a one-byte 3 followed by three four-byte face indices.
faces_uints = np.full((len(faces_array), 13), 3, dtype=np.uint8)
faces_uints[:, 1:] = faces_array.astype(np.uint32).view(np.uint8)
faces_recs = np.zeros(
len(faces_array),
dtype=[("count", np.uint8), ("vertex_indices", np.uint32, 3)],
)
faces_recs["count"] = 3
faces_recs["vertex_indices"] = faces_array
faces_uints = faces_recs.view(np.uint8)
if isinstance(f, BytesIO):
f.write(faces_uints.tobytes())
else:

View File

@ -353,6 +353,11 @@ class TestMeshPlyIO(TestCaseMixin, unittest.TestCase):
save_ply(file, verts=verts, faces=faces, verts_normals=normals)
file.close()
def test_contiguity_unimportant(self):
verts = torch.rand(32, 3)
self._test_save_load(verts, torch.randint(30, size=(10, 3)))
self._test_save_load(verts, torch.randint(30, size=(3, 10)).T)
def test_empty_save_load(self):
# Vertices + empty faces
verts = torch.tensor([[0.1, 0.2, 0.3]])