trimesh.path

trimesh.path

Handle 2D and 3D vector paths such as those contained in an SVG or DXF file.

class trimesh.path.Path2D(entities: Iterable[Entity] | None = None, vertices: Buffer | _SupportsArray[dtype[Any]] | _NestedSequence[_SupportsArray[dtype[Any]]] | bool | int | float | complex | str | bytes | _NestedSequence[bool | int | float | complex | str | bytes] | None = None, metadata: dict | None = None, process: bool = True, colors=None, **kwargs)

Bases: Path

Hold multiple vector curves (lines, arcs, splines, etc) in 3D.

apply_obb()

Transform the current path so that its OBB is axis aligned and OBB center is at the origin.

Returns:

obb – Homogeneous transformation matrix

Return type:

(3, 3) float

apply_scale(scale)

Apply a 2D scale to the current Path2D.

Parameters:

scale (float or (2,) float) – Scale to apply in-place.

property area

Return the area of the polygons interior.

Returns:

area – Total area of polygons minus interiors

Return type:

float

property body_count

Returns a count of the number of unconnected polygons that may contain other curves but aren’t contained themselves.

Returns:

body_count – Number of unconnected independent polygons.

Return type:

int

connected_paths(path_id, include_self=False)

Given an index of self.paths find other paths which overlap with that path.

Parameters:

  • path_id (int) – Index of self.paths

  • include_self (bool) – Should the result include path_id or not

Returns:

path_ids – Indexes of self.paths that overlap input path_id

Return type:

(n, ) int

property enclosure

Undirected graph object of polygon enclosure.

Returns:

enclosure – Enclosure graph of self.polygons by index.

Return type:

networkx.Graph

property enclosure_directed

Directed graph of polygon enclosure.

Returns:

enclosure_directed – Directed graph: child nodes are fully contained by their parent node.

Return type:

networkx.DiGraph

property enclosure_shell

A dictionary of path indexes which are ‘shell’ paths, and values of ‘hole’ paths.

Returns:

corresponding – {index of self.paths of shell : [indexes of holes]}

Return type:

dict

extrude(height, **kwargs)

Extrude the current 2D path into a 3D mesh.

Parameters:

  • height (float, how far to extrude the profile)

  • kwargs (passed directly to meshpy.triangle.build:) –

    triangle.build(mesh_info,

    verbose=False, refinement_func=None, attributes=False, volume_constraints=True, max_volume=None, allow_boundary_steiner=True, allow_volume_steiner=True, quality_meshing=True, generate_edges=None, generate_faces=False, min_angle=None)

Returns:

mesh

Return type:

trimesh object representing extruded polygon

property identifier

A unique identifier for the path.

Returns:

identifier – Unique identifier

Return type:

(5,) float

property identifier_hash

Return a hash of the identifier.

Returns:

hashed – SHA256 hash of the identifier vector.

Return type:

(64,) str

medial_axis(resolution=None, clip=None)

Find the approximate medial axis based on a voronoi diagram of evenly spaced points on the boundary of the polygon.

Parameters:

  • resolution (None or float) – Distance between each sample on the polygon boundary

  • clip (None, or (2,) float) – Min, max number of samples

Returns:

medial – Contains only medial axis of Path

Return type:

Path2D object

property obb

Get a transform that centers and aligns the OBB of the referenced vertices with the XY axis.

Returns:

obb – Homogeneous transformation matrix

Return type:

(3, 3) float

property path_valid
returns: path_valid – Indexes of self.paths self.polygons_closed

which are valid polygons.

Return type:

(n,) bool

plot_discrete(show=False, annotations=True)

Plot the closed curves of the path.

plot_entities(show=False, annotations=True, color=None)

Plot the entities of the path with no notion of topology.

Parameters:

  • show (bool) – Open a window immediately or not

  • annotations (bool) – Call an entities custom plot function.

  • color (str) – Override entity colors and make them all this color.

property polygons_closed: ndarray[Any, dtype[_ScalarType_co]]

Cycles in the vertex graph, as shapely.geometry.Polygons. These are polygon objects for every closed circuit, with no notion of whether a polygon is a hole or an area. Every polygon in this list will have an exterior, but NO interiors.

Returns:

polygons_closed

Return type:

(n,) list of shapely.geometry.Polygon objects

property polygons_full: list

A list of shapely.geometry.Polygon objects with interiors created by checking which closed polygons enclose which other polygons.

Returns:

full – Polygons containing interiors

Return type:

(len(self.root),) shapely.geometry.Polygon

rasterize(pitch=None, origin=None, resolution=None, fill=True, width=None, **kwargs)

Rasterize a Path2D object into a boolean image (“mode 1”).

Parameters:

  • pitch (float or (2,) float) – Length(s) in model space of pixel edges

  • origin ((2,) float) – Origin position in model space

  • resolution ((2,) int) – Resolution in pixel space

  • fill (bool) – If True will return closed regions as filled

  • width (int) – If not None will draw outline this wide (pixels)

Returns:

raster – Rasterized version of closed regions.

Return type:

PIL.Image object, mode 1

property root

Which indexes of self.paths/self.polygons_closed are root curves, also known as ‘shell’ or ‘exterior.

Returns:

root – List of indexes

Return type:

(n,) int

sample(count, **kwargs)

Use rejection sampling to generate random points inside a polygon.

Parameters:

  • count (int) – Number of points to return If there are multiple bodies, there will be up to count * bodies points returned

  • factor (float) – How many points to test per loop IE, count * factor

  • max_iter (int,) – Maximum number of intersection loops to run, total points sampled is count * factor * max_iter

Returns:

hit – Random points inside polygon

Return type:

(n, 2) float

show(annotations=True)

Plot the current Path2D object using matplotlib.

simplify(**kwargs)

Return a version of the current path with colinear segments merged, and circles entities replacing segmented circular paths.

Returns:

simplified

Return type:

Path2D object

simplify_spline(smooth=0.0002, verbose=False)

Convert paths into b-splines.

Parameters:

  • smooth (float) – How much the spline should smooth the curve

  • verbose (bool) – Print detailed log messages

Returns:

simplified – Discrete curves replaced with splines

Return type:

Path2D

split(**kwargs)

If the current Path2D consists of n ‘root’ curves, split them into a list of n Path2D objects

Returns:

split – Each connected region and interiors

Return type:

(n,) list of Path2D objects

to_3D(transform=None)

Convert 2D path to 3D path on the XY plane.

Parameters:

transform ((4, 4) float) – If passed, will transform vertices. If not passed and ‘to_3D’ is in self.metadata that transform will be used.

Returns:

path_3D – 3D version of current path

Return type:

Path3D

triangulate(**kwargs)

Create a region- aware triangulation of the 2D path.

Parameters:

**kwargs (dict) – Passed to trimesh.creation.triangulate_polygon

Returns:

  • vertices ((n, 2) float) – 2D vertices of triangulation

  • faces ((n, 3) int) – Indexes of vertices for triangles

class trimesh.path.Path3D(entities: Iterable[Entity] | None = None, vertices: Buffer | _SupportsArray[dtype[Any]] | _NestedSequence[_SupportsArray[dtype[Any]]] | bool | int | float | complex | str | bytes | _NestedSequence[bool | int | float | complex | str | bytes] | None = None, metadata: dict | None = None, process: bool = True, colors=None, **kwargs)

Bases: Path

Hold multiple vector curves (lines, arcs, splines, etc) in 3D.

show(**kwargs)

Show the current Path3D object.

to_planar(to_2D=None, normal=None, check=True)

Check to see if current vectors are all coplanar.

If they are, return a Path2D and a transform which will transform the 2D representation back into 3 dimensions

Parameters:

  • to_2D ((4,4) float) – Homogeneous transformation matrix to apply, If not passed a plane will be fitted to vertices.

  • normal ((3,) float, or None) – Approximate normal of direction of plane If to_2D is not specified sign will be applied to fit plane normal

  • check (bool) – If True: Raise a ValueError if points aren’t coplanar

Returns:

  • planar (trimesh.path.Path2D) – Current path transformed onto plane

  • to_3D ((4,4) float) – Homeogenous transformations to move planar back into 3D space