trimesh.path.path¶
path.py¶
A module designed to work with vector paths such as those stored in a DXF or SVG file.

class
trimesh.path.path.
Path
(entities=None, vertices=None, metadata=None, process=True, colors=None, **kwargs)¶ Bases:
trimesh.parent.Geometry
A Path object consists of vertices and entities. Vertices are a simple (n, dimension) float array of points in space.
Entities are a list of objects representing geometric primitives, such as Lines, Arcs, BSpline, etc. All entities reference vertices by index, so any transform applied to the simple vertex array is applied to the entity.

apply_layer
(name)¶ Apply a layer name to every entity in the path.
 Parameters
name (str) – Apply layer name to every entity

apply_transform
(transform)¶ Apply a transformation matrix to the current path in place
 Parameters
transform ((d+1, d+1) float) – Homogeneous transformations for vertices

property
bounds
¶ Return the axis aligned bounding box of the current path.
 Returns
bounds – AABB with (min, max) coordinates
 Return type
(2, dimension) float

property
centroid
¶ Return the centroid of axis aligned bounding box enclosing all entities of the path object.
 Returns
centroid – Approximate centroid of the path
 Return type
(d,) float

property
colors
¶ Colors are stored perentity.
 Returns
colors – RGBA colors for each entity
 Return type
(len(entities), 4) uint8

colors_crc
()¶ A CRC of the current entity colors.
 Returns
crc – CRC of the current entity colors
 Return type
int

convert_units
(desired, guess=False)¶ Convert the units of the current drawing in place.
 Parameters
desired (str) – Unit system to convert to
guess (bool) – If True will attempt to guess units

copy
()¶ Get a copy of the current mesh
 Returns
copied – Copy of self
 Return type
Path object

crc
()¶ A CRC of the current vertices and entities.
 Returns
crc – CRC of entity points and vertices
 Return type
int

property
dangling
¶ List of entities that aren’t included in a closed path
 Returns
dangling – Index of self.entities
 Return type
(n,) int

property
discrete
¶ A sequence of connected vertices in space, corresponding to self.paths.
 Returns
discrete – A sequence of (m*, dimension) float
 Return type
(len(self.paths),)

discretize_path
(path)¶ Given a list of entities, return a list of connected points.
 Parameters
path ((n,) int) – Indexes of self.entities
 Returns
discrete – Linear segment path.
 Return type
(m, dimension)

property
entities
¶ The actual entities making up the path.
 Returns
entities – Entities such as Line, Arc, or BSpline curves
 Return type

explode
()¶ Turn every multi segment entity into single segment entities in place.

export
(file_obj=None, file_type=None, **kwargs)¶ Export the path to a file object or return data.
 Parameters
file_obj (None, str, or file object) – File object or string to export to
file_type (None or str) – Type of file: dxf, dict, svg
 Returns
exported – Exported as specified type
 Return type
bytes or str

property
extents
¶ The size of the axis aligned bounding box.
 Returns
extents – Edge length of AABB
 Return type
(dimension,) float

fill_gaps
(distance=0.025)¶ Find vertices without degree 2 and try to connect to other vertices. Operations are done inplace.
 Parameters
distance (float) – Connect vertices up to this distance

property
is_closed
¶ Are all entities connected to other entities.
 Returns
closed – Every entity is connected at its ends
 Return type
bool

property
is_empty
¶ Are any entities defined for the current path.
 Returns
empty – True if no entities are defined
 Return type
bool

property
kdtree
¶ A KDTree object holding the vertices of the path.
 Returns
kdtree – Object holding self.vertices
 Return type
scipy.spatial.cKDTree

property
layers
¶ Get a list of the layer for every entity.
 Returns
layers – Whatever is stored in each entity.layer
 Return type
(len(entities), ) any

property
length
¶ The total discretized length of every entity.
 Returns
length
 Return type
float, summed length of every entity

md5
()¶ An MD5 hash of the current vertices and entities.
 Returns
md5 – Appended MD5 hashes
 Return type
str

merge_vertices
(digits=None)¶ Merges vertices which are identical and replace references by altering self.entities and self.vertices
 Parameters
digits (None, or int) – How many digits to consider when merging vertices

property
paths
¶ Sequence of closed paths, encoded by entity index.
 Returns
paths – Referencing self.entities
 Return type
(n,) sequence of (*,) int

process
()¶ Apply basic cleaning functions to the Path object in place.

property
referenced_vertices
¶ Which vertices are referenced by an entity.
 Returns
referenced_vertices
 Return type
(n,) int, indexes of self.vertices

remove_duplicate_entities
()¶ Remove entities that are duplicated
Notes
self.entities: length same or shorter

remove_entities
(entity_ids)¶ Remove entities by index.
 Parameters
entity_ids ((n,) int) – Indexes of self.entities to remove

remove_invalid
()¶ Remove entities which declare themselves invalid
Notes
self.entities: shortened

remove_unreferenced_vertices
()¶ Removes all vertices which aren’t used by an entity.
Notes
self.vertices : reordered and shortened self.entities : entity.points references updated

replace_vertex_references
(mask)¶ Replace the vertex index references in every entity.
 Parameters
mask ((len(self.vertices), ) int) – Contains new vertex indexes
Notes
 entity.points in self.entities
Replaced by mask[entity.points]

rezero
()¶ Translate so that every vertex is positive in the current mesh is positive.
 Returns
matrix – Homogeneous transformations that was applied to the current Path object.
 Return type
(dimension + 1, dimension + 1) float

property
scale
¶ What is a representitive number that reflects the magnitude of the world holding the paths, for numerical comparisons.
 Returns
scale – Approximate size of the world holding this path
 Return type
float

scene
()¶ Get a scene object containing the current Path3D object.
 Returns
scene
 Return type
trimesh.scene.Scene object containing current path

to_dict
()¶

property
units
¶ If there are units defined in self.metadata return them.
 Returns
units – Current unit system
 Return type
str

property
vertex_graph
¶ Return a networkx.Graph object for the entity connectiviy
 graphnetworkx.Graph
Holds vertex indexes

property
vertex_nodes
¶ Get a list of which vertex indices are nodes, which are either endpoints or points where the entity makes a direction change.
 Returns
nodes – Indexes of self.vertices which are nodes
 Return type
(n, 2) int

property
vertices
¶


class
trimesh.path.path.
Path2D
(entities=None, vertices=None, metadata=None, process=True, colors=None, **kwargs)¶ Bases:
trimesh.path.path.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 inplace.

property
area
¶ Return the area of the polygons interior.
 Returns
area
 Return type
float, total area of polygons minus interiors

property
body_count
¶

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
¶ Networkx Graph object of polygon enclosure.

property
enclosure_directed
¶ Networkx DiGraph of polygon enclosure

property
enclosure_shell
¶ A dictionary of path indexes which are ‘shell’ paths, and values of ‘hole’ paths.
 Returns
corresponding
 Return type
dict, {index of self.paths of shell : [indexes of holes]}

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
 Return type
(5,) float, unique identifier

property
identifier_md5
¶ Return an MD5 of the identifier

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 – which are valid polygons :rtype: (n,) bool, indexes of self.paths self.polygons_closed

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

property
polygons_closed
¶ 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
¶ 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, origin, 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
 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
 Return type
(n,) int, list of indexes

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 bsplines.
 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

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 metadata that transform will be used.
 Returns
path_3D
 Return type
Path3D version of current path

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.path.
Path3D
(entities=None, vertices=None, metadata=None, process=True, colors=None, **kwargs)¶ Bases:
trimesh.path.path.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
