def test_interpolate_attributes_grad(self):
verts = torch.randn((4, 3), dtype=torch.float32)
faces = torch.tensor([[2, 1, 0], [3, 1, 0]], dtype=torch.int64)
vert_tex = torch.tensor(
[[0, 1, 0], [0, 1, 1], [1, 1, 0], [1, 1, 1]],
dtype=torch.float32,
requires_grad=True,
)
tex = Textures(verts_rgb=vert_tex[None, :])
mesh = Meshes(verts=[verts], faces=[faces], textures=tex)
pix_to_face = torch.tensor([0, 1], dtype=torch.int64).view(1, 1, 1, 2)
barycentric_coords = torch.tensor([[0.5, 0.3, 0.2], [0.3, 0.6, 0.1]],
dtype=torch.float32).view(
1, 1, 1, 2, -1)
fragments = Fragments(
pix_to_face=pix_to_face,
bary_coords=barycentric_coords,
zbuf=torch.ones_like(pix_to_face),
dists=torch.ones_like(pix_to_face),
)
grad_vert_tex = torch.tensor(
[
[0.3, 0.3, 0.3],
[0.9, 0.9, 0.9],
[0.5, 0.5, 0.5],
[0.3, 0.3, 0.3],
],
dtype=torch.float32,
)
texels = interpolate_vertex_colors(fragments, mesh)
texels.sum().backward()
self.assertTrue(hasattr(vert_tex, "grad"))
self.assertTrue(torch.allclose(vert_tex.grad, grad_vert_tex[None, :]))
def test_interpolate_attributes(self):
"""
This tests both interpolate_vertex_colors as well as
interpolate_face_attributes.
"""
verts = torch.randn((4, 3), dtype=torch.float32)
faces = torch.tensor([[2, 1, 0], [3, 1, 0]], dtype=torch.int64)
vert_tex = torch.tensor([[0, 1, 0], [0, 1, 1], [1, 1, 0], [1, 1, 1]],
dtype=torch.float32)
tex = Textures(verts_rgb=vert_tex[None, :])
mesh = Meshes(verts=[verts], faces=[faces], textures=tex)
pix_to_face = torch.tensor([0, 1], dtype=torch.int64).view(1, 1, 1, 2)
barycentric_coords = torch.tensor([[0.5, 0.3, 0.2], [0.3, 0.6, 0.1]],
dtype=torch.float32).view(
1, 1, 1, 2, -1)
expected_vals = torch.tensor([[0.5, 1.0, 0.3], [0.3, 1.0, 0.9]],
dtype=torch.float32).view(1, 1, 1, 2, -1)
fragments = Fragments(
pix_to_face=pix_to_face,
bary_coords=barycentric_coords,
zbuf=torch.ones_like(pix_to_face),
dists=torch.ones_like(pix_to_face),
)
texels = interpolate_vertex_colors(fragments, mesh)
self.assertTrue(torch.allclose(texels, expected_vals[None, :]))
