hub/venv/lib/python3.7/site-packages/trimesh/collision.py

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import numpy as np
import collections
try:
# pip install python-fcl
import fcl
except BaseException:
fcl = None
class ContactData(object):
"""
Data structure for holding information about a collision contact.
"""
def __init__(self, names, contact):
"""
Initialize a ContactData.
Parameters
----------
names : list of str
The names of the two objects in order.
contact : fcl.Contact
The contact in question.
"""
self.names = set(names)
self._inds = {
names[0]: contact.b1,
names[1]: contact.b2
}
self._point = contact.pos
@property
def point(self):
"""
The 3D point of intersection for this contact.
Returns
-------
point : (3,) float
The intersection point.
"""
return self._point
def index(self, name):
"""
Returns the index of the face in contact for the mesh with
the given name.
Parameters
----------
name : str
The name of the target object.
Returns
-------
index : int
The index of the face in collision
"""
return self._inds[name]
class DistanceData(object):
"""
Data structure for holding information about a distance query.
"""
def __init__(self, names, result):
"""
Initialize a DistanceData.
Parameters
----------
names : list of str
The names of the two objects in order.
contact : fcl.DistanceResult
The distance query result.
"""
self.names = set(names)
self._inds = {
names[0]: result.b1,
names[1]: result.b2
}
self._points = {
names[0]: result.nearest_points[0],
names[1]: result.nearest_points[1]
}
self._distance = result.min_distance
@property
def distance(self):
"""
Returns the distance between the two objects.
Returns
-------
distance : float
The euclidean distance between the objects.
"""
return self._distance
def index(self, name):
"""
Returns the index of the closest face for the mesh with
the given name.
Parameters
----------
name : str
The name of the target object.
Returns
-------
index : int
The index of the face in collisoin.
"""
return self._inds[name]
def point(self, name):
"""
The 3D point of closest distance on the mesh with the given name.
Parameters
----------
name : str
The name of the target object.
Returns
-------
point : (3,) float
The closest point.
"""
return self._points[name]
class CollisionManager(object):
"""
A mesh-mesh collision manager.
"""
def __init__(self):
"""
Initialize a mesh-mesh collision manager.
"""
if fcl is None:
raise ValueError('No FCL Available!')
# {name: {geom:, obj}}
self._objs = {}
# {id(bvh) : str, name}
# unpopulated values will return None
self._names = collections.defaultdict(lambda: None)
# cache BVH objects
# {mesh.md5(): fcl.BVHModel object}
self._bvh = {}
self._manager = fcl.DynamicAABBTreeCollisionManager()
self._manager.setup()
def add_object(self,
name,
mesh,
transform=None):
"""
Add an object to the collision manager.
If an object with the given name is already in the manager,
replace it.
Parameters
----------
name : str
An identifier for the object
mesh : Trimesh object
The geometry of the collision object
transform : (4,4) float
Homogeneous transform matrix for the object
"""
# if no transform passed, assume identity transform
if transform is None:
transform = np.eye(4)
transform = np.asanyarray(transform, dtype=np.float32)
if transform.shape != (4, 4):
raise ValueError('transform must be (4,4)!')
# create or recall from cache BVH
bvh = self._get_BVH(mesh)
# create the FCL transform from (4,4) matrix
t = fcl.Transform(transform[:3, :3], transform[:3, 3])
o = fcl.CollisionObject(bvh, t)
# Add collision object to set
if name in self._objs:
self._manager.unregisterObject(self._objs[name])
self._objs[name] = {'obj': o,
'geom': bvh}
# store the name of the geometry
self._names[id(bvh)] = name
self._manager.registerObject(o)
self._manager.update()
return o
def remove_object(self, name):
"""
Delete an object from the collision manager.
Parameters
----------
name : str
The identifier for the object
"""
if name in self._objs:
self._manager.unregisterObject(self._objs[name]['obj'])
self._manager.update(self._objs[name]['obj'])
# remove objects from _objs
geom_id = id(self._objs.pop(name)['geom'])
# remove names
self._names.pop(geom_id)
else:
raise ValueError('{} not in collision manager!'.format(name))
def set_transform(self, name, transform):
"""
Set the transform for one of the manager's objects.
This replaces the prior transform.
Parameters
----------
name : str
An identifier for the object already in the manager
transform : (4,4) float
A new homogeneous transform matrix for the object
"""
if name in self._objs:
o = self._objs[name]['obj']
o.setRotation(transform[:3, :3])
o.setTranslation(transform[:3, 3])
self._manager.update(o)
else:
raise ValueError('{} not in collision manager!'.format(name))
def in_collision_single(self,
mesh,
transform=None,
return_names=False,
return_data=False):
"""
Check a single object for collisions against all objects in the
manager.
Parameters
----------
mesh : Trimesh object
The geometry of the collision object
transform : (4,4) float
Homogeneous transform matrix
return_names : bool
If true, a set is returned containing the names
of all objects in collision with the object
return_data : bool
If true, a list of ContactData is returned as well
Returns
------------
is_collision : bool
True if a collision occurs and False otherwise
names : set of str
[OPTIONAL] The set of names of objects that collided with the
provided one
contacts : list of ContactData
[OPTIONAL] All contacts detected
"""
if transform is None:
transform = np.eye(4)
# Create FCL data
b = self._get_BVH(mesh)
t = fcl.Transform(transform[:3, :3], transform[:3, 3])
o = fcl.CollisionObject(b, t)
# Collide with manager's objects
cdata = fcl.CollisionData()
if return_names or return_data:
cdata = fcl.CollisionData(request=fcl.CollisionRequest(
num_max_contacts=100000,
enable_contact=True))
self._manager.collide(o, cdata, fcl.defaultCollisionCallback)
result = cdata.result.is_collision
# If we want to return the objects that were collision, collect them.
objs_in_collision = set()
contact_data = []
if return_names or return_data:
for contact in cdata.result.contacts:
cg = contact.o1
if cg == b:
cg = contact.o2
name = self._extract_name(cg)
names = (name, '__external')
if cg == contact.o2:
names = reversed(names)
if return_names:
objs_in_collision.add(name)
if return_data:
contact_data.append(ContactData(names, contact))
if return_names and return_data:
return result, objs_in_collision, contact_data
elif return_names:
return result, objs_in_collision
elif return_data:
return result, contact_data
else:
return result
def in_collision_internal(self, return_names=False, return_data=False):
"""
Check if any pair of objects in the manager collide with one another.
Parameters
----------
return_names : bool
If true, a set is returned containing the names
of all pairs of objects in collision.
return_data : bool
If true, a list of ContactData is returned as well
Returns
-------
is_collision : bool
True if a collision occurred between any pair of objects
and False otherwise
names : set of 2-tup
The set of pairwise collisions. Each tuple
contains two names in alphabetical order indicating
that the two corresponding objects are in collision.
contacts : list of ContactData
All contacts detected
"""
cdata = fcl.CollisionData()
if return_names or return_data:
cdata = fcl.CollisionData(request=fcl.CollisionRequest(
num_max_contacts=100000, enable_contact=True))
self._manager.collide(cdata, fcl.defaultCollisionCallback)
result = cdata.result.is_collision
objs_in_collision = set()
contact_data = []
if return_names or return_data:
for contact in cdata.result.contacts:
names = (self._extract_name(contact.o1),
self._extract_name(contact.o2))
if return_names:
objs_in_collision.add(tuple(sorted(names)))
if return_data:
contact_data.append(ContactData(names, contact))
if return_names and return_data:
return result, objs_in_collision, contact_data
elif return_names:
return result, objs_in_collision
elif return_data:
return result, contact_data
else:
return result
def in_collision_other(self, other_manager,
return_names=False, return_data=False):
"""
Check if any object from this manager collides with any object
from another manager.
Parameters
-------------------
other_manager : CollisionManager
Another collision manager object
return_names : bool
If true, a set is returned containing the names
of all pairs of objects in collision.
return_data : bool
If true, a list of ContactData is returned as well
Returns
-------------
is_collision : bool
True if a collision occurred between any pair of objects
and False otherwise
names : set of 2-tup
The set of pairwise collisions. Each tuple
contains two names (first from this manager,
second from the other_manager) indicating
that the two corresponding objects are in collision.
contacts : list of ContactData
All contacts detected
"""
cdata = fcl.CollisionData()
if return_names or return_data:
cdata = fcl.CollisionData(
request=fcl.CollisionRequest(
num_max_contacts=100000,
enable_contact=True))
self._manager.collide(other_manager._manager,
cdata,
fcl.defaultCollisionCallback)
result = cdata.result.is_collision
objs_in_collision = set()
contact_data = []
if return_names or return_data:
for contact in cdata.result.contacts:
reverse = False
names = (self._extract_name(contact.o1),
other_manager._extract_name(contact.o2))
if names[0] is None:
names = (self._extract_name(contact.o2),
other_manager._extract_name(contact.o1))
reverse = True
if return_names:
objs_in_collision.add(names)
if return_data:
if reverse:
names = reversed(names)
contact_data.append(ContactData(names, contact))
if return_names and return_data:
return result, objs_in_collision, contact_data
elif return_names:
return result, objs_in_collision
elif return_data:
return result, contact_data
else:
return result
def min_distance_single(self,
mesh,
transform=None,
return_name=False,
return_data=False):
"""
Get the minimum distance between a single object and any
object in the manager.
Parameters
---------------
mesh : Trimesh object
The geometry of the collision object
transform : (4,4) float
Homogeneous transform matrix for the object
return_names : bool
If true, return name of the closest object
return_data : bool
If true, a DistanceData object is returned as well
Returns
-------------
distance : float
Min distance between mesh and any object in the manager
name : str
The name of the object in the manager that was closest
data : DistanceData
Extra data about the distance query
"""
if transform is None:
transform = np.eye(4)
# Create FCL data
b = self._get_BVH(mesh)
t = fcl.Transform(transform[:3, :3], transform[:3, 3])
o = fcl.CollisionObject(b, t)
# Collide with manager's objects
ddata = fcl.DistanceData()
if return_data:
ddata = fcl.DistanceData(
fcl.DistanceRequest(enable_nearest_points=True),
fcl.DistanceResult()
)
self._manager.distance(o, ddata, fcl.defaultDistanceCallback)
distance = ddata.result.min_distance
# If we want to return the objects that were collision, collect them.
name, data = None, None
if return_name or return_data:
cg = ddata.result.o1
if cg == b:
cg = ddata.result.o2
name = self._extract_name(cg)
names = (name, '__external')
if cg == ddata.result.o2:
names = reversed(names)
data = DistanceData(names, ddata.result)
if return_name and return_data:
return distance, name, data
elif return_name:
return distance, name
elif return_data:
return distance, data
else:
return distance
def min_distance_internal(self, return_names=False, return_data=False):
"""
Get the minimum distance between any pair of objects in the manager.
Parameters
-------------
return_names : bool
If true, a 2-tuple is returned containing the names
of the closest objects.
return_data : bool
If true, a DistanceData object is returned as well
Returns
-----------
distance : float
Min distance between any two managed objects
names : (2,) str
The names of the closest objects
data : DistanceData
Extra data about the distance query
"""
ddata = fcl.DistanceData()
if return_data:
ddata = fcl.DistanceData(
fcl.DistanceRequest(enable_nearest_points=True),
fcl.DistanceResult()
)
self._manager.distance(ddata, fcl.defaultDistanceCallback)
distance = ddata.result.min_distance
names, data = None, None
if return_names or return_data:
names = (self._extract_name(ddata.result.o1),
self._extract_name(ddata.result.o2))
data = DistanceData(names, ddata.result)
names = tuple(sorted(names))
if return_names and return_data:
return distance, names, data
elif return_names:
return distance, names
elif return_data:
return distance, data
else:
return distance
def min_distance_other(self, other_manager,
return_names=False, return_data=False):
"""
Get the minimum distance between any pair of objects,
one in each manager.
Parameters
----------
other_manager : CollisionManager
Another collision manager object
return_names : bool
If true, a 2-tuple is returned containing
the names of the closest objects.
return_data : bool
If true, a DistanceData object is returned as well
Returns
-----------
distance : float
The min distance between a pair of objects,
one from each manager.
names : 2-tup of str
A 2-tuple containing two names (first from this manager,
second from the other_manager) indicating
the two closest objects.
data : DistanceData
Extra data about the distance query
"""
ddata = fcl.DistanceData()
if return_data:
ddata = fcl.DistanceData(
fcl.DistanceRequest(enable_nearest_points=True),
fcl.DistanceResult()
)
self._manager.distance(other_manager._manager,
ddata,
fcl.defaultDistanceCallback)
distance = ddata.result.min_distance
names, data = None, None
if return_names or return_data:
reverse = False
names = (self._extract_name(ddata.result.o1),
other_manager._extract_name(ddata.result.o2))
if names[0] is None:
reverse = True
names = (self._extract_name(ddata.result.o2),
other_manager._extract_name(ddata.result.o1))
dnames = tuple(names)
if reverse:
dnames = reversed(dnames)
data = DistanceData(dnames, ddata.result)
if return_names and return_data:
return distance, names, data
elif return_names:
return distance, names
elif return_data:
return distance, data
else:
return distance
def _get_BVH(self, mesh):
"""
Get a BVH for a mesh.
Parameters
-------------
mesh : Trimesh
Mesh to create BVH for
Returns
--------------
bvh : fcl.BVHModel
BVH object of source mesh
"""
bvh = mesh_to_BVH(mesh)
return bvh
def _extract_name(self, geom):
"""
Retrieve the name of an object from the manager by its
CollisionObject, or return None if not found.
Parameters
-----------
geom : CollisionObject or BVHModel
Input model
Returns
------------
names : hashable
Name of input geometry
"""
return self._names[id(geom)]
def mesh_to_BVH(mesh):
"""
Create a BVHModel object from a Trimesh object
Parameters
-----------
mesh : Trimesh
Input geometry
Returns
------------
bvh : fcl.BVHModel
BVH of input geometry
"""
bvh = fcl.BVHModel()
bvh.beginModel(num_tris_=len(mesh.faces),
num_vertices_=len(mesh.vertices))
bvh.addSubModel(verts=mesh.vertices,
triangles=mesh.faces)
bvh.endModel()
return bvh
def scene_to_collision(scene):
"""
Create collision objects from a trimesh.Scene object.
Parameters
------------
scene : trimesh.Scene
Scene to create collision objects for
Returns
------------
manager : CollisionManager
CollisionManager for objects in scene
objects: {node name: CollisionObject}
Collision objects for nodes in scene
"""
manager = CollisionManager()
objects = {}
for node in scene.graph.nodes_geometry:
T, geometry = scene.graph[node]
objects[node] = manager.add_object(name=node,
mesh=scene.geometry[geometry],
transform=T)
return manager, objects