Point Sampling
PointCloud(data=None)
Bases: Mesh
A data structure for representing point clouds
Attributes:
Name | Type | Description |
---|---|---|
vertices |
DataContainer
|
the container for all vertices |
__str__ |
str
|
Representation of the object and its elements as a string. |
id_vertices
property
Shortcut for range(len(self.vertices))
append(x)
Shortcut for self.vertices.append(x)
, since we can only append elements in the 'vertices' container
PolyLine(data=None)
Bases: Mesh
A data structure for representing polylines.
Attributes:
Name | Type | Description |
---|---|---|
vertices |
DataContainer
|
the container for all vertices |
edges |
DataContainer
|
the container for all edges |
__str__ |
Representation of the object and its elements as a string. |
id_edges
property
Shortcut for range(len(self.edges))
id_vertices
property
Shortcut for range(len(self.vertices))
SurfaceMesh(data=None)
Bases: Mesh
A data structure for representing polygonal surfaces.
Attributes:
Name | Type | Description |
---|---|---|
vertices |
DataContainer
|
the container for all vertices |
edges |
DataContainer
|
the container for all edges |
faces |
DataContainer
|
the container for all faces |
face_corners |
DataContainer
|
the container for all corner of faces |
boundary_edges |
list
|
list of all edge indices on the boundary |
interior_edges |
list
|
list of all interior edge indices (all edges \ boundary_edges) |
boundary_vertices |
list
|
list of all vertex indices on the boundary |
interior_vertices |
list
|
list of all interior verticex indices (all vertices \ boundary_vertices) |
connectivity |
_SurfaceConnectivity
|
the connectivity utility class |
id_corners
property
Shortcut for range(len(self.face_corners))
id_edges
property
Shortcut for range(len(self.edges))
id_faces
property
Shortcut for range(len(self.faces))
id_vertices
property
Shortcut for range(len(self.vertices))
clear_boundary_data()
Clear all boundary data. Next call to a boundary/interior container or method will recompute everything
is_edge_on_border(u, v)
whether edge (u,v) is a boundary edge or not
Parameters:
Name | Type | Description | Default |
---|---|---|---|
u
|
int
|
vertex id |
required |
v
|
int
|
vertex id |
required |
Returns:
Name | Type | Description |
---|---|---|
bool |
bool
|
whether edge (u,v) is a boundary edge or not. Returns False if (u,v) is not a valid edge. |
is_quad()
Checks if the mesh is a quadrangulation
Returns:
Name | Type | Description |
---|---|---|
bool |
bool
|
True if the mesh is quadrangular (all faces are quad) |
is_triangular()
Checks if the mesh is a triangulation
Returns:
Name | Type | Description |
---|---|---|
bool |
bool
|
True if the mesh is triangular (all faces are triangles) |
is_vertex_on_border(u)
whether vertex u
is a boundary vertex or not.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
u
|
int
|
vertex id |
required |
Returns:
Name | Type | Description |
---|---|---|
bool |
bool
|
whether vertex |
ith_vertex_of_face(fid, i)
helper function to get the i-th vertex of a face, i.e. self.faces[fid][i]
Parameters:
Name | Type | Description | Default |
---|---|---|---|
fid
|
int
|
face id |
required |
i
|
int
|
vertex id in face. Should be 0 <= vid < len(face) |
required |
Returns:
Name | Type | Description |
---|---|---|
int |
int
|
the id of the i-th vertex in face |
pt_of_face(fid)
point coordinates of vertices of face fid
Parameters:
Name | Type | Description | Default |
---|---|---|---|
fid
|
int
|
face id |
required |
Returns:
Name | Type | Description |
---|---|---|
Iterable |
iterator of Vec objects representing point coordinates of vertices |
VolumeMesh(data=None)
Bases: Mesh
id_cells
property
Shortcut for range(len(self.cells))
id_corners
property
Shortcut for range(len(self.face_corners))
id_edges
property
Shortcut for range(len(self.edges))
id_faces
property
Shortcut for range(len(self.faces))
id_vertices
property
Shortcut for range(len(self.vertices))
is_edge_on_border(*args)
Simple test to determine if a given edge is on the boundary of the mesh.
Returns:
Name | Type | Description |
---|---|---|
bool |
bool
|
Returns True if the given edge is on the boundary of the mesh. |
is_face_on_border(*args)
Simple test to determine if a given face is on the boundary of the mesh.
Returns:
Name | Type | Description |
---|---|---|
bool |
bool
|
Returns True is the given face exists and is on the boundary of the mesh |
is_tetrahedral()
Returns:
Name | Type | Description |
---|---|---|
bool |
bool
|
True if the mesh is tetrahedral (all cells are tetrahedra) |
sample_AABB(box, n_pts, mode='uniform', return_point_cloud=False)
Sample a point cloud uniformly at random inside an axis-aligned bounding box. Works by sampling the unit cube and applying an affine transformation.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
box
|
AABB
|
the domain of sampling |
required |
n_pts
|
int
|
number of points to sample. If mode is 'grid', the function may return a slightly smaller number of points (nearest perfect n-th root). |
required |
mode
|
str
|
sampling mode. 'uniform' or 'grid'. Uniform takes points at random, while 'grid' generates a grid of regularly spaced points. |
'uniform'
|
return_point_cloud
|
bool
|
whether to compile the points in a PointCloud object or return the raw numpy array. Is ignored if the bounding box has dimension >3. Defaults to False. |
False
|
Raises:
Type | Description |
---|---|
Exception
|
fails if the bounding box is empty. |
ValueError
|
fails if the dimension of the box is > 3 and return_point_cloud is set to True, so that no PointCloud object with dim > 3 is created. |
Returns:
Type | Description |
---|---|
PointCloud | np.ndarray: a sampled point cloud of |
sample_ball(center, radius, n_pts, return_point_cloud=False)
Samples points uniformly inside a 3D ball.
Parameters:
Name | Type | Description | Default |
---|---|---|---|
center
|
Vec
|
center of the ball |
required |
radius
|
float
|
radius of the ball |
required |
n_pts
|
int
|
number of points to sample |
required |
return_point_cloud
|
bool
|
whether to compile the points in a PointCloud object or return the raw numpy array. Defaults to False. |
False
|
Returns:
Type | Description |
---|---|
PointCloud | np.ndarray: a sampled point cloud of |
sample_polyline(mesh, n_pts, return_point_cloud=False)
Sample a point cloud uniformly at random from a polyline
Parameters:
Name | Type | Description | Default |
---|---|---|---|
mesh
|
PolyLine
|
the input polyline |
required |
n_pts
|
int
|
number of points to sample |
required |
return_point_cloud
|
bool
|
whether to compile the points in a PointCloud object or return the raw numpy array. Defaults to False. |
False
|
Returns:
Type | Description |
---|---|
PointCloud | np.ndarray: a sampled point cloud of |
sample_sphere(center, radius, n_pts, return_point_cloud=False)
Samples points uniformly on the surface of a 3D sphere
Parameters:
Name | Type | Description | Default |
---|---|---|---|
center
|
Vec
|
center of the sphere |
required |
radius
|
float
|
radius of the spheres |
required |
n_pts
|
int
|
number of points to sample |
required |
return_point_cloud
|
bool
|
whether to compile the points in a PointCloud object or return the raw numpy array. Defaults to False. |
False
|
Returns:
Type | Description |
---|---|
PointCloud | np.ndarray: a sampled point cloud of |
sample_surface(mesh, n_pts, return_point_cloud=False, return_normals=False)
Sample a point cloud uniformly at random from a surface mesh
Parameters:
Name | Type | Description | Default |
---|---|---|---|
mesh
|
SurfaceMesh
|
input mesh |
required |
n_pts
|
int
|
number of points to sample |
required |
return_point_cloud
|
bool
|
whether to compile the points in a PointCloud object or return the raw numpy array. Defaults to False. |
False
|
return_normals
|
bool
|
wether to assign the normal of the faces to sampled points. Only has effect if return_point_cloud is set to True. Defaults to False. |
False
|
Returns:
Type | Description |
---|---|
PointCloud | np.ndarray: a sampled point cloud of |
|
np.ndarray : the associated normals (if sample_normals was set to True) |