def test_poisson_disk_sampling(self): import point_cloud_utils as pcu import numpy as np # v is a nv by 3 NumPy array of vertices # f is an nf by 3 NumPy array of face indexes into v # n is a nv by 3 NumPy array of vertex normals v, f, n = pcu.read_obj(os.path.join(self.test_path, "cube_twist.obj")) bbox = np.max(v, axis=0) - np.min(v, axis=0) bbox_diag = np.linalg.norm(bbox) # Generate very dense random samples on the mesh (v, f, n) # Note that this function works with no normals, just pass in an empty array np.array([], dtype=v.dtype) # v_dense is an array with shape (100*v.shape[0], 3) where each row is a point on the mesh (v, f) # n_dense is an array with shape (100*v.shape[0], 3) where each row is a the normal of a point in v_dense v_dense, n_dense = pcu.sample_mesh_random(v, f, n, num_samples=v.shape[0] * 100) # Downsample v_dense to be from a blue noise distribution: # # v_poisson is a downsampled version of v where points are separated by approximately # `radius` distance, use_geodesic_distance indicates that the distance should be measured on the mesh. # # n_poisson are the corresponding normals of v_poisson v_poisson, n_poisson = pcu.sample_mesh_poisson_disk( v_dense, f, n_dense, radius=0.01 * bbox_diag, use_geodesic_distance=True)
def sample_pointcloud_mesh(obj_path): off_v, off_f, off_n = pcu.read_obj(obj_path) if off_n.shape[0] != off_v.shape[0]: off_n = np.array([]) v_dense, n_dense = pcu.sample_mesh_random(off_v, off_f, off_n, num_samples=point_num) return v_dense
def shootCloud(V, F, density: int = 256, occlusion=80, shuffle=False): cloud, _ = pcu.sample_mesh_random(V, F, np.array([], dtype=V.dtype), num_samples=density + occlusion) tree = KDTree(cloud) # find occlusion nearest neighbours and remove if occlusion > 0: x = np.random.randint(len(cloud)) _, nearest_ind = tree.query(cloud[x].reshape(-1, 3), k=occlusion) cloud = np.delete(cloud, nearest_ind, axis=0) # unorder the data if shuffle: np.random.shuffle(cloud) return cloud
def test_mesh_sampling(self): import point_cloud_utils as pcu import numpy as np # v is a nv by 3 NumPy array of vertices # f is an nf by 3 NumPy array of face indexes into v # n is a nv by 3 NumPy array of vertex normals if they are specified, otherwise an empty array v, f, n = pcu.read_obj(os.path.join(self.test_path, "cube_twist.obj")) bbox = np.max(v, axis=0) - np.min(v, axis=0) bbox_diag = np.linalg.norm(bbox) f_idx1, bc1 = pcu.sample_mesh_random(v, f, num_samples=1000, random_seed=1234567) f_idx2, bc2 = pcu.sample_mesh_random(v, f, num_samples=1000, random_seed=1234567) f_idx3, bc3 = pcu.sample_mesh_random(v, f, num_samples=1000, random_seed=7654321) self.assertTrue(np.all(f_idx1 == f_idx2)) self.assertTrue(np.all(bc1 == bc2)) self.assertFalse(np.all(f_idx1 == f_idx3)) self.assertFalse(np.all(bc1 == bc3)) # Generate very dense random samples on the mesh (v, f) f_idx, bc = pcu.sample_mesh_random(v, f, num_samples=v.shape[0] * 4) v_dense = (v[f[f_idx]] * bc[:, np.newaxis]).sum(1) s_idx = pcu.downsample_point_cloud_poisson_disk(v_dense, 0, 0.1*bbox_diag, random_seed=1234567) s_idx2 = pcu.downsample_point_cloud_poisson_disk(v_dense, 0, 0.1*bbox_diag, random_seed=1234567) s_idx3 = pcu.downsample_point_cloud_poisson_disk(v_dense, 0, 0.1 * bbox_diag, random_seed=7654321) self.assertTrue(np.all(s_idx == s_idx2)) if s_idx3.shape == s_idx.shape: self.assertFalse(np.all(s_idx == s_idx3)) else: self.assertFalse(s_idx.shape == s_idx3.shape) # Ensure we can request more samples than vertices and get something reasonable s_idx_0 = pcu.downsample_point_cloud_poisson_disk(v_dense, 2*v_dense.shape[0], random_seed=1234567) s_idx = pcu.downsample_point_cloud_poisson_disk(v_dense, 1000, random_seed=1234567) s_idx2 = pcu.downsample_point_cloud_poisson_disk(v_dense, 1000, random_seed=1234567) s_idx3 = pcu.downsample_point_cloud_poisson_disk(v_dense, 1000, random_seed=7654321) self.assertTrue(np.all(s_idx == s_idx2)) if s_idx3.shape == s_idx.shape: self.assertFalse(np.all(s_idx == s_idx3)) else: self.assertFalse(s_idx.shape == s_idx3.shape) f_idx1, bc1 = pcu.sample_mesh_poisson_disk(v, f, num_samples=1000, random_seed=1234567, use_geodesic_distance=True, oversampling_factor=5.0) f_idx2, bc2 = pcu.sample_mesh_poisson_disk(v, f, num_samples=1000, random_seed=1234567, use_geodesic_distance=True, oversampling_factor=5.0) f_idx3, bc3 = pcu.sample_mesh_poisson_disk(v, f, num_samples=1000, random_seed=7654321, use_geodesic_distance=True, oversampling_factor=5.0) self.assertTrue(np.all(f_idx1 == f_idx2)) self.assertTrue(np.all(bc1 == bc2)) if f_idx1.shape == f_idx3.shape: self.assertFalse(np.all(f_idx1 == f_idx3)) if bc1.shape == bc3.shape: self.assertFalse(np.all(bc1 == bc3)) f_idx1, bc1 = pcu.sample_mesh_poisson_disk(v, f, num_samples=-1, radius=0.01*bbox_diag, random_seed=1234567, oversampling_factor=5.0) f_idx2, bc2 = pcu.sample_mesh_poisson_disk(v, f, num_samples=-1, radius=0.01*bbox_diag, random_seed=1234567, oversampling_factor=5.0) f_idx3, bc3 = pcu.sample_mesh_poisson_disk(v, f, num_samples=-1, radius=0.01*bbox_diag, random_seed=7654321, oversampling_factor=5.0) self.assertTrue(np.all(f_idx1 == f_idx2)) self.assertTrue(np.all(bc1 == bc2)) if f_idx1.shape == f_idx3.shape: self.assertFalse(np.all(f_idx1 == f_idx3)) if bc1.shape == bc3.shape: self.assertFalse(np.all(bc1 == bc3))