"""
parent.py
-------------
The base class for Trimesh, PointCloud, and Scene objects
"""
import abc
import numpy as np
from . import bounds, caching
from . import transformations as tf
from .caching import cache_decorator
from .constants import tol
from .typed import Dict, Optional
from .util import ABC
[docs]
class Geometry(ABC):
"""
`Geometry` is the parent class for all geometry.
By decorating a method with `abc.abstractmethod` it means
the objects that inherit from `Geometry` MUST implement
those methods.
"""
# geometry should have a dict to store loose metadata
metadata: Dict
@property
@abc.abstractmethod
def bounds(self):
pass
@property
@abc.abstractmethod
def extents(self):
pass
@property
@abc.abstractmethod
def is_empty(self) -> bool:
pass
[docs]
def __hash__(self):
"""
Get a hash of the current geometry.
Returns
---------
hash : int
Hash of current graph and geometry.
"""
return self._data.__hash__()
[docs]
@abc.abstractmethod
def copy(self):
pass
[docs]
@abc.abstractmethod
def show(self):
pass
@abc.abstractmethod
def __add__(self, other):
pass
[docs]
@abc.abstractmethod
def export(self, file_obj, file_type=None):
pass
[docs]
def __repr__(self):
"""
Print quick summary of the current geometry without
computing properties.
Returns
-----------
repr : str
Human readable quick look at the geometry.
"""
elements = []
if hasattr(self, "vertices"):
# for Trimesh and PointCloud
elements.append(f"vertices.shape={self.vertices.shape}")
if hasattr(self, "faces"):
# for Trimesh
elements.append(f"faces.shape={self.faces.shape}")
if hasattr(self, "geometry") and isinstance(self.geometry, dict):
# for Scene
elements.append(f"len(geometry)={len(self.geometry)}")
if "Voxel" in type(self).__name__:
# for VoxelGrid objects
elements.append(str(self.shape)[1:-1])
if "file_name" in self.metadata:
display = self.metadata["file_name"]
elements.append(f"name=`{display}`")
return "<trimesh.{}({})>".format(type(self).__name__, ", ".join(elements))
[docs]
def apply_translation(self, translation):
"""
Translate the current mesh.
Parameters
----------
translation : (3,) float
Translation in XYZ
"""
translation = np.asanyarray(translation, dtype=np.float64)
if translation.shape == (2,):
# create a planar matrix if we were passed a 2D offset
return self.apply_transform(tf.planar_matrix(offset=translation))
elif translation.shape != (3,):
raise ValueError("Translation must be (3,) or (2,)!")
# manually create a translation matrix
matrix = np.eye(4)
matrix[:3, 3] = translation
return self.apply_transform(matrix)
[docs]
def apply_scale(self, scaling):
"""
Scale the mesh.
Parameters
----------
scaling : float or (3,) float
Scale factor to apply to the mesh
"""
matrix = tf.scale_and_translate(scale=scaling)
# apply_transform will work nicely even on negative scales
return self.apply_transform(matrix)
[docs]
def __radd__(self, other):
"""
Concatenate the geometry allowing concatenation with
built in `sum()` function:
`sum(Iterable[trimesh.Trimesh])`
Parameters
------------
other : Geometry
Geometry or 0
Returns
----------
concat : Geometry
Geometry of combined result
"""
if other == 0:
# adding 0 to a geometry never makes sense
return self
# otherwise just use the regular add function
return self.__add__(type(self)(other))
@cache_decorator
def scale(self) -> float:
"""
A loosely specified "order of magnitude scale" for the
geometry which always returns a value and can be used
to make code more robust to large scaling differences.
It returns the diagonal of the axis aligned bounding box
or if anything is invalid or undefined, `1.0`.
Returns
----------
scale : float
Approximate order of magnitude scale of the geometry.
"""
# if geometry is empty return 1.0
if self.extents is None:
return 1.0
# get the length of the AABB diagonal
scale = float((self.extents**2).sum() ** 0.5)
if scale < tol.zero:
return 1.0
return scale
@property
def units(self) -> Optional[str]:
"""
Definition of units for the mesh.
Returns
----------
units : str
Unit system mesh is in, or None if not defined
"""
return self.metadata.get("units", None)
@units.setter
def units(self, value: str) -> None:
"""
Define the units of the current mesh.
"""
self.metadata["units"] = str(value).lower().strip()
class Geometry3D(Geometry):
"""
The `Geometry3D` object is the parent object of geometry objects
which are three dimensional, including Trimesh, PointCloud,
and Scene objects.
"""
@caching.cache_decorator
def bounding_box(self):
"""
An axis aligned bounding box for the current mesh.
Returns
----------
aabb : trimesh.primitives.Box
Box object with transform and extents defined
representing the axis aligned bounding box of the mesh
"""
from . import primitives
transform = np.eye(4)
# translate to center of axis aligned bounds
transform[:3, 3] = self.bounds.mean(axis=0)
aabb = primitives.Box(transform=transform, extents=self.extents, mutable=False)
return aabb
@caching.cache_decorator
def bounding_box_oriented(self):
"""
An oriented bounding box for the current mesh.
Returns
---------
obb : trimesh.primitives.Box
Box object with transform and extents defined
representing the minimum volume oriented
bounding box of the mesh
"""
from . import bounds, primitives
to_origin, extents = bounds.oriented_bounds(self)
obb = primitives.Box(
transform=np.linalg.inv(to_origin), extents=extents, mutable=False
)
return obb
@caching.cache_decorator
def bounding_sphere(self):
"""
A minimum volume bounding sphere for the current mesh.
Note that the Sphere primitive returned has an unpadded
exact `sphere_radius` so while the distance of every vertex
of the current mesh from sphere_center will be less than
sphere_radius, the faceted sphere primitive may not
contain every vertex.
Returns
--------
minball : trimesh.primitives.Sphere
Sphere primitive containing current mesh
"""
from . import nsphere, primitives
center, radius = nsphere.minimum_nsphere(self)
minball = primitives.Sphere(center=center, radius=radius, mutable=False)
return minball
@caching.cache_decorator
def bounding_cylinder(self):
"""
A minimum volume bounding cylinder for the current mesh.
Returns
--------
mincyl : trimesh.primitives.Cylinder
Cylinder primitive containing current mesh
"""
from . import bounds, primitives
kwargs = bounds.minimum_cylinder(self)
mincyl = primitives.Cylinder(mutable=False, **kwargs)
return mincyl
@caching.cache_decorator
def bounding_primitive(self):
"""
The minimum volume primitive (box, sphere, or cylinder) that
bounds the mesh.
Returns
---------
bounding_primitive : object
Smallest primitive which bounds the mesh:
trimesh.primitives.Sphere
trimesh.primitives.Box
trimesh.primitives.Cylinder
"""
options = [
self.bounding_box_oriented,
self.bounding_sphere,
self.bounding_cylinder,
]
volume_min = np.argmin([i.volume for i in options])
bounding_primitive = options[volume_min]
return bounding_primitive
def apply_obb(self, **kwargs):
"""
Apply the oriented bounding box transform to the current mesh.
This will result in a mesh with an AABB centered at the
origin and the same dimensions as the OBB.
Parameters
------------
kwargs
Passed through to `bounds.oriented_bounds`
Returns
----------
matrix : (4, 4) float
Transformation matrix that was applied
to mesh to move it into OBB frame
"""
# save the pre-transform volume
if tol.strict and hasattr(self, "volume"):
volume = self.volume
# calculate the OBB passing keyword arguments through
matrix, extents = bounds.oriented_bounds(self, **kwargs)
# apply the transform
self.apply_transform(matrix)
if tol.strict:
# obb transform should not have changed volume
if hasattr(self, "volume"):
assert np.isclose(self.volume, volume)
# overall extents should match what we expected
assert np.allclose(self.extents, extents)
return matrix
