def test_sample_locations_between_surfaces(depth, n_points):
inner = flat_mesh(5, 7)
outer = inner[0] + [0., 0., 1.], inner[1]
locations = surface._sample_locations_between_surfaces(
outer, inner, np.eye(4), n_points=n_points, depth=depth)
if depth is None:
# can be simplified when we drop support for np 1.15
# (broadcasting linspace)
expected = np.asarray(
[np.linspace(b, a, n_points)
for (a, b) in zip(inner[0].ravel(), outer[0].ravel())])
expected = np.rollaxis(
expected.reshape((*outer[0].shape, n_points)), 2, 1)
else:
offsets = ([[0., 0., - z] for z in depth])
expected = np.asarray([vertex + offsets for vertex in outer[0]])
assert np.allclose(locations, expected)
N_T = 10
u, v = np.mgrid[:N_T, :N_Z]
triangulation = matplotlib.tri.Triangulation(u.flatten(), v.flatten())
angles = u.flatten() * 2 * np.pi / N_T
x, y = np.cos(angles), np.sin(angles)
z = v.flatten() * 2 / N_Z
mesh = [np.asarray([x, y, z]).T, triangulation.triangles]
inner_mesh = [[.7, .7, 1.] * mesh[0], triangulation.triangles]
#########################################################################
# Get the locations from which vol_to_surf would draw its samples
#########################################################################
nested_sample_points = surface._sample_locations_between_surfaces(
mesh, inner_mesh, np.eye(4))
line_sample_points = surface._line_sample_locations(
mesh, np.eye(4), segment_half_width=.2, n_points=6)
ball_sample_points = surface._ball_sample_locations(
mesh, np.eye(4), ball_radius=.15, n_points=20)
######################################################################
# Plot the mesh and the sample locations
######################################################################
fig = plt.figure()
ax = plt.subplot(projection='3d')
ax.view_init(67, -42)