import os import numpy as np import collections from .. import util from .. import units from .. import convex from .. import caching from .. import grouping from .. import transformations from .. import bounds as bounds_module from ..exchange import gltf from ..parent import Geometry from . import cameras from . import lighting from .transforms import TransformForest class Scene(Geometry): """ A simple scene graph which can be rendered directly via pyglet/openGL or through other endpoints such as a raytracer. Meshes are added by name, which can then be moved by updating transform in the transform tree. """ def __init__(self, geometry=None, base_frame='world', metadata={}, graph=None, camera=None, lights=None, camera_transform=None): """ Create a new Scene object. Parameters ------------- geometry : Trimesh, Path2D, Path3D PointCloud or list Geometry to initially add to the scene base_frame : str or hashable Name of base frame metadata : dict Any metadata about the scene graph : TransformForest or None A passed transform graph to use camera : Camera or None A passed camera to use lights : [trimesh.scene.lighting.Light] or None A passed lights to use camera_transform : (4, 4) float or None Camera transform in the base frame """ # mesh name : Trimesh object self.geometry = collections.OrderedDict() # create a new graph self.graph = TransformForest(base_frame=base_frame) # create our cache self._cache = caching.Cache(id_function=self.md5) # add passed geometry to scene self.add_geometry(geometry) # hold metadata about the scene self.metadata = {} self.metadata.update(metadata) if graph is not None: # if we've been passed a graph override the default self.graph = graph self.camera = camera self.lights = lights self.camera_transform = camera_transform def apply_transform(self, transform): """ Apply a transform to every geometry in the scene. Parameters -------------- transform : (4, 4) Homogeneous transformation matrix """ for geometry in self.geometry.values(): geometry.apply_transform(transform) def add_geometry(self, geometry, node_name=None, geom_name=None, parent_node_name=None, transform=None): """ Add a geometry to the scene. If the mesh has multiple transforms defined in its metadata, they will all be copied into the TransformForest of the current scene automatically. Parameters ---------- geometry : Trimesh, Path2D, Path3D PointCloud or list Geometry to initially add to the scene base_frame : str or hashable Name of base frame metadata : dict Any metadata about the scene graph : TransformForest or None A passed transform graph to use Returns ---------- node_name : str Name of node in self.graph """ if geometry is None: return # PointCloud objects will look like a sequence elif util.is_sequence(geometry): # if passed a sequence add all elements return [self.add_geometry( geometry=value, node_name=node_name, geom_name=geom_name, parent_node_name=parent_node_name, transform=transform) for value in geometry] elif isinstance(geometry, dict): # if someone passed us a dict of geometry for key, value in geometry.items(): self.add_geometry(value, geom_name=key) return elif isinstance(geometry, Scene): # concatenate current scene with passed scene concat = self + geometry # replace geometry in-place self.geometry.clear() self.geometry.update(concat.geometry) # replace graph data with concatenated graph self.graph.transforms = concat.graph.transforms return elif not hasattr(geometry, 'vertices'): util.log.warning('unknown type ({}) added to scene!'.format( type(geometry).__name__)) # get or create a name to reference the geometry by if geom_name is not None: # if name is passed use it name = geom_name elif 'name' in geometry.metadata: # if name is in metadata use it name = geometry.metadata['name'] elif 'file_name' in geometry.metadata: name = geometry.metadata['file_name'] else: # try to create a simple name name = 'geometry_' + str(len(self.geometry)) # if its already taken add a unique random string to it if name in self.geometry: name += ':' + util.unique_id().upper() # save the geometry reference self.geometry[name] = geometry # create a unique node name if not passed if node_name is None: # if the name of the geometry is also a transform node if name in self.graph.nodes: # a random unique identifier unique = util.unique_id(increment=len(self.geometry)) # geometry name + UUID node_name = name + '_' + unique.upper() else: # otherwise make the transform node name the same as the geom node_name = name if transform is None: # create an identity transform from parent_node transform = np.eye(4) self.graph.update(frame_to=node_name, frame_from=parent_node_name, matrix=transform, geometry=name, geometry_flags={'visible': True}) return node_name def delete_geometry(self, names): """ Delete one more multiple geometries from the scene and also remove any node in the transform graph which references it. Parameters -------------- name : hashable Name that references self.geometry """ # make sure we have a set we can check if util.is_string(names): names = [names] names = set(names) # remove the geometry reference from relevant nodes self.graph.remove_geometries(names) # remove the geometries from our geometry store [self.geometry.pop(name, None) for name in names] def md5(self): """ MD5 of scene which will change when meshes or transforms are changed Returns -------- hashed : str MD5 hash of scene """ # start with transforms hash return util.md5_object(self._hashable()) def crc(self): return caching.crc32(self._hashable()) def _hashable(self): hashes = [self.graph.md5()] for g in self.geometry.values(): if hasattr(g, 'md5'): hashes.append(g.md5()) elif hasattr(g, 'tostring'): hashes.append(str(hash(g.tostring()))) else: # try to just straight up hash # this may raise errors hashes.append(str(hash(g))) hashable = ''.join(sorted(hashes)).encode('utf-8') return hashable @property def is_empty(self): """ Does the scene have anything in it. Returns ---------- is_empty: bool, True if nothing is in the scene """ is_empty = len(self.geometry) == 0 return is_empty @property def is_valid(self): """ Is every geometry connected to the root node. Returns ----------- is_valid : bool Does every geometry have a transform """ if len(self.geometry) == 0: return True try: referenced = {self.graph[i][1] for i in self.graph.nodes_geometry} except BaseException: # if connectivity to world frame is broken return false return False # every geometry is referenced ok = referenced == set(self.geometry.keys()) return ok @caching.cache_decorator def bounds_corners(self): """ A list of points that represent the corners of the AABB of every geometry in the scene. This can be useful if you want to take the AABB in a specific frame. Returns ----------- corners: (n, 3) float, points in space """ # the saved corners of each instance corners_inst = [] # (n, 3) float corners of each geometry corners_geom = {k: bounds_module.corners(v.bounds) for k, v in self.geometry.items() if v.bounds is not None} if len(corners_geom) == 0: return np.array([]) for node_name in self.graph.nodes_geometry: # access the transform and geometry name from node transform, geometry_name = self.graph[node_name] # not all nodes have associated geometry if geometry_name not in corners_geom: continue # transform geometry corners into where # the instance of the geometry is located corners_inst.extend( transformations.transform_points( corners_geom[geometry_name], transform)) # make corners numpy array corners_inst = np.array(corners_inst, dtype=np.float64) return corners_inst @caching.cache_decorator def bounds(self): """ Return the overall bounding box of the scene. Returns -------- bounds : (2, 3) float or None Position of [min, max] bounding box Returns None if no valid bounds exist """ corners = self.bounds_corners if len(corners) == 0: return None bounds = np.array([corners.min(axis=0), corners.max(axis=0)]) return bounds @caching.cache_decorator def extents(self): """ Return the axis aligned box size of the current scene. Returns ---------- extents : (3,) float Bounding box sides length """ return np.diff(self.bounds, axis=0).reshape(-1) @caching.cache_decorator def scale(self): """ The approximate scale of the mesh Returns ----------- scale : float The mean of the bounding box edge lengths """ scale = (self.extents ** 2).sum() ** .5 return scale @caching.cache_decorator def centroid(self): """ Return the center of the bounding box for the scene. Returns -------- centroid : (3) float Point for center of bounding box """ centroid = np.mean(self.bounds, axis=0) return centroid @caching.cache_decorator def area(self): """ What is the summed area of every geometry which has area. Returns ------------ area : float Summed area of every instanced geometry """ # get the area of every geometry that has an area property areas = {n: g.area for n, g in self.geometry.items() if hasattr(g, 'area')} # get the name of every geometry instance in the scene geoms = [self.graph[n][1] for n in self.graph.nodes_geometry] # sum the area for every instanced geometry area = sum(areas[n] for n in geoms if n in geoms) return area @caching.cache_decorator def triangles(self): """ Return a correctly transformed polygon soup of the current scene. Returns ---------- triangles : (n, 3, 3) float Triangles in space """ triangles = collections.deque() triangles_node = collections.deque() for node_name in self.graph.nodes_geometry: # which geometry does this node refer to transform, geometry_name = self.graph[node_name] # get the actual potential mesh instance geometry = self.geometry[geometry_name] if not hasattr(geometry, 'triangles'): continue # append the (n, 3, 3) triangles to a sequence triangles.append( transformations.transform_points( geometry.triangles.copy().reshape((-1, 3)), matrix=transform)) # save the node names for each triangle triangles_node.append( np.tile(node_name, len(geometry.triangles))) # save the resulting nodes to the cache self._cache['triangles_node'] = np.hstack(triangles_node) triangles = np.vstack(triangles).reshape((-1, 3, 3)) return triangles @caching.cache_decorator def triangles_node(self): """ Which node of self.graph does each triangle come from. Returns --------- triangles_index : (len(self.triangles),) Node name for each triangle """ populate = self.triangles # NOQA return self._cache['triangles_node'] @caching.cache_decorator def geometry_identifiers(self): """ Look up geometries by identifier MD5 Returns --------- identifiers : dict {Identifier MD5: key in self.geometry} """ identifiers = {mesh.identifier_md5: name for name, mesh in self.geometry.items()} return identifiers @caching.cache_decorator def duplicate_nodes(self): """ Return a sequence of node keys of identical meshes. Will include meshes with different geometry but identical spatial hashes as well as meshes repeated by self.nodes. Returns ----------- duplicates : (m) sequenc Keys of self.nodes that represent identical geometry """ # if there is no geometry we can have no duplicate nodes if len(self.geometry) == 0: return [] # geometry name : md5 of mesh mesh_hash = {k: int(m.identifier_md5, 16) for k, m in self.geometry.items()} # the name of nodes in the scene graph with geometry node_names = np.array(self.graph.nodes_geometry) # the geometry names for each node in the same order node_geom = np.array([self.graph[i][1] for i in node_names]) # the mesh md5 for each node in the same order node_hash = np.array([mesh_hash[v] for v in node_geom]) # indexes of identical hashes node_groups = grouping.group(node_hash) # sequence of node names where each # sublist has identical geometry duplicates = [np.sort(node_names[g]).tolist() for g in node_groups] return duplicates def deduplicated(self): """ Return a new scene where each unique geometry is only included once and transforms are discarded. Returns ------------- dedupe : Scene One copy of each unique geometry from scene """ # collect geometry geometry = {} # loop through groups of identical nodes for group in self.duplicate_nodes: # get the name of the geometry name = self.graph[group[0]][1] # collect our unique collection of geometry geometry[name] = self.geometry[name] return Scene(geometry) def set_camera(self, angles=None, distance=None, center=None, resolution=None, fov=None): """ Create a camera object for self.camera, and add a transform to self.graph for it. If arguments are not passed sane defaults will be figured out which show the mesh roughly centered. Parameters ----------- angles : (3,) float Initial euler angles in radians distance : float Distance from centroid center : (3,) float Point camera should be center on camera : Camera object Object that stores camera parameters """ if fov is None: fov = np.array([60, 45]) # if no geometry nothing to set camera to if len(self.geometry) == 0: self._camera = cameras.Camera(fov=fov) self.graph[self._camera.name] = np.eye(4) return self._camera # set with no rotation by default if angles is None: angles = np.zeros(3) rotation = transformations.euler_matrix(*angles) transform = cameras.look_at( self.bounds_corners, fov=fov, rotation=rotation, distance=distance, center=center) if hasattr(self, '_camera') and self._camera is not None: self._camera.fov = fov if resolution is not None: self._camera.resolution = resolution else: # create a new camera object self._camera = cameras.Camera(fov=fov, resolution=resolution) self.graph[self._camera.name] = transform return self._camera @property def camera_transform(self): """ Get camera transform in the base frame Returns ------- camera_transform : (4, 4) float Camera transform in the base frame """ return self.graph[self.camera.name][0] def camera_rays(self): """ Calculate the trimesh.scene.Camera origin and ray direction vectors. Returns one ray per pixel as set in camera.resolution Returns -------------- origin: (n, 3) float Ray origins in space vectors: (n, 3) float Ray direction unit vectors in world coordinates pixels : (n, 2) int Which pixel does each ray correspond to in an image """ # get the unit vectors of the camera vectors, pixels = self.camera.to_rays() # find our scene's transform for the camera transform = self.camera_transform # apply the rotation to the unit ray direction vectors vectors = transformations.transform_points( vectors, transform, translate=False) # camera origin is single point so extract from origins = (np.ones_like(vectors) * transformations.translation_from_matrix(transform)) return origins, vectors, pixels @camera_transform.setter def camera_transform(self, camera_transform): """ Set the camera transform in the base frame Parameters ---------- camera_transform : (4, 4) float Camera transform in the base frame """ if camera_transform is None: return self.graph[self.camera.name] = camera_transform @property def camera(self): """ Get the single camera for the scene. If not manually set one will abe automatically generated. Returns ---------- camera : trimesh.scene.Camera Camera object defined for the scene """ # no camera set for the scene yet if not self.has_camera: # will create a camera with everything in view return self.set_camera() assert self._camera is not None return self._camera @camera.setter def camera(self, camera): """ Set a camera object for the Scene. Parameters ----------- camera : trimesh.scene.Camera Camera object for the scene """ if camera is None: return self._camera = camera @property def has_camera(self): return hasattr(self, '_camera') and self._camera is not None @property def lights(self): """ Get a list of the lights in the scene. If nothing is set it will generate some automatically. Returns ------------- lights : [trimesh.scene.lighting.Light] Lights in the scene. """ if not hasattr(self, '_lights') or self._lights is None: # do some automatic lighting lights, transforms = lighting.autolight(self) # assign the transforms to the scene graph for L, T in zip(lights, transforms): self.graph[L.name] = T # set the lights self._lights = lights return self._lights @lights.setter def lights(self, lights): """ Assign a list of light objects to the scene Parameters -------------- lights : [trimesh.scene.lighting.Light] Lights in the scene. """ self._lights = lights def rezero(self): """ Move the current scene so that the AABB of the whole scene is centered at the origin. Does this by changing the base frame to a new, offset base frame. """ if self.is_empty or np.allclose(self.centroid, 0.0): # early exit since what we want already exists return # the transformation to move the overall scene to AABB centroid matrix = np.eye(4) matrix[:3, 3] = -self.centroid # we are going to change the base frame new_base = str(self.graph.base_frame) + '_I' self.graph.update(frame_from=new_base, frame_to=self.graph.base_frame, matrix=matrix) self.graph.base_frame = new_base def dump(self, concatenate=False): """ Append all meshes in scene freezing transforms. Parameters ------------ concatenate : bool If True, concatenate results into single mesh Returns ---------- dumped : (n,) Trimesh or Trimesh Trimesh objects transformed to their location the scene.graph """ result = [] for node_name in self.graph.nodes_geometry: transform, geometry_name = self.graph[node_name] # get a copy of the geometry current = self.geometry[geometry_name].copy() # move the geometry vertices into the requested frame current.apply_transform(transform) current.metadata['name'] = node_name # save to our list of meshes result.append(current) if concatenate: return util.concatenate(result) return np.array(result) @caching.cache_decorator def convex_hull(self): """ The convex hull of the whole scene Returns --------- hull: Trimesh object, convex hull of all meshes in scene """ points = util.vstack_empty([m.vertices for m in self.dump()]) hull = convex.convex_hull(points) return hull def export(self, file_obj=None, file_type=None, **kwargs): """ Export a snapshot of the current scene. Parameters ---------- file_obj : str, file-like, or None File object to export to file_type : str or None What encoding to use for meshes IE: dict, dict64, stl Returns ---------- export : bytes Only returned if file_obj is None """ # if we weren't passed a file type extract from file_obj if file_type is None: if util.is_string(file_obj): file_type = str(file_obj).split('.')[-1] else: raise ValueError('file_type not specified!') # always remove whitepace and leading characters file_type = file_type.strip().lower().lstrip('.') # now handle our different scene export types if file_type == 'gltf': data = gltf.export_gltf(self, **kwargs) elif file_type == 'glb': data = gltf.export_glb(self, **kwargs) elif file_type == 'dict': from ..exchange.export import scene_to_dict data = scene_to_dict(self) elif file_type == 'obj': from ..exchange.obj import export_obj data = export_obj(self) elif file_type == 'dict64': from ..exchange.export import scene_to_dict data = scene_to_dict(self, use_base64=True) else: raise ValueError( 'unsupported export format: {}'.format(file_type)) # now write the data or return bytes of result if hasattr(file_obj, 'write'): # if it's just a regular file object file_obj.write(data) elif util.is_string(file_obj): # assume strings are file paths file_path = os.path.expanduser( os.path.abspath(file_obj)) if util.is_string(data): mode = 'w' else: mode = 'wb' with open(file_path, mode) as f: f.write(data) else: # no writeable file object so return data return data def save_image(self, resolution=None, **kwargs): """ Get a PNG image of a scene. Parameters ----------- resolution : (2,) int Resolution to render image **kwargs Passed to SceneViewer constructor Returns ----------- png : bytes Render of scene as a PNG """ from ..viewer import render_scene png = render_scene(scene=self, resolution=resolution, **kwargs) return png @property def units(self): """ Get the units for every model in the scene, and raise a ValueError if there are mixed units. Returns ----------- units : str Units for every model in the scene """ existing = [i.units for i in self.geometry.values()] if any(existing[0] != e for e in existing): # if all of our geometry doesn't have the same units already # this function will only do some hot nonsense raise ValueError('models in scene have inconsistent units!') return existing[0] @units.setter def units(self, value): """ Set the units for every model in the scene without converting any units just setting the tag. Parameters ------------ value : str Value to set every geometry unit value to """ for m in self.geometry.values(): m.units = value def convert_units(self, desired, guess=False): """ If geometry has units defined convert them to new units. Returns a new scene with geometries and transforms scaled. Parameters ---------- desired : str Desired final unit system: 'inches', 'mm', etc. guess : bool Is the converter allowed to guess scale when models don't have it specified in their metadata. Returns ---------- scaled : trimesh.Scene Copy of scene with scaling applied and units set for every model """ # if there is no geometry do nothing if len(self.geometry) == 0: return self.copy() current = self.units if current is None: # will raise ValueError if not in metadata # and not allowed to guess current = units.units_from_metadata(self, guess=guess) # find the float conversion scale = units.unit_conversion(current=current, desired=desired) # exit early if our current units are the same as desired units if np.isclose(scale, 1.0): result = self.copy() else: result = self.scaled(scale=scale) # apply the units to every geometry of the scaled result result.units = desired return result def explode(self, vector=None, origin=None): """ Explode a scene around a point and vector. Parameters ----------- vector : (3,) float or float Explode radially around a direction vector or spherically origin : (3,) float Point to explode around """ if origin is None: origin = self.centroid if vector is None: vector = self.scale / 25.0 vector = np.asanyarray(vector, dtype=np.float64) origin = np.asanyarray(origin, dtype=np.float64) for node_name in self.graph.nodes_geometry: transform, geometry_name = self.graph[node_name] centroid = self.geometry[geometry_name].centroid # transform centroid into nodes location centroid = np.dot(transform, np.append(centroid, 1))[:3] if vector.shape == (): # case where our vector is a single number offset = (centroid - origin) * vector elif np.shape(vector) == (3,): projected = np.dot(vector, (centroid - origin)) offset = vector * projected else: raise ValueError('explode vector wrong shape!') transform[0:3, 3] += offset self.graph[node_name] = transform def scaled(self, scale): """ Return a copy of the current scene, with meshes and scene transforms scaled to the requested factor. Parameters ----------- scale : float Factor to scale meshes and transforms Returns ----------- scaled : trimesh.Scene A copy of the current scene but scaled """ scale = float(scale) # matrix for 2D scaling scale_2D = np.eye(3) * scale # matrix for 3D scaling scale_3D = np.eye(4) * scale # preallocate transforms and geometries nodes = np.array(self.graph.nodes_geometry) transforms = np.zeros((len(nodes), 4, 4)) geometries = [None] * len(nodes) # collect list of transforms for i, node in enumerate(nodes): transforms[i], geometries[i] = self.graph[node] # result is a copy result = self.copy() # remove all existing transforms result.graph.clear() for group in grouping.group(geometries): # hashable reference to self.geometry geometry = geometries[group[0]] # original transform from world to geometry original = transforms[group[0]] # transform for geometry new_geom = np.dot(scale_3D, original) if result.geometry[geometry].vertices.shape[1] == 2: # if our scene is 2D only scale in 2D result.geometry[geometry].apply_transform(scale_2D) else: # otherwise apply the full transform result.geometry[geometry].apply_transform(new_geom) for node, T in zip(nodes[group], transforms[group]): # generate the new transforms transform = util.multi_dot( [scale_3D, T, np.linalg.inv(new_geom)]) # apply scale to translation transform[:3, 3] *= scale # update scene with new transforms result.graph.update(frame_to=node, matrix=transform, geometry=geometry) return result def copy(self): """ Return a deep copy of the current scene Returns ---------- copied : trimesh.Scene Copy of the current scene """ # use the geometries copy method to # allow them to handle references to unpickle-able objects geometry = {n: g.copy() for n, g in self.geometry.items()} if not hasattr(self, '_camera') or self._camera is None: # if no camera set don't include it camera = None else: # otherwise get a copy of the camera camera = self.camera.copy() # create a new scene with copied geometry and graph copied = Scene(geometry=geometry, graph=self.graph.copy(), camera=camera) return copied def show(self, viewer=None, **kwargs): """ Display the current scene. Parameters ----------- viewer: str What kind of viewer to open, including 'gl' to open a pyglet window, 'notebook' for a jupyter notebook or None kwargs : dict Includes `smooth`, which will turn on or off automatic smooth shading """ if viewer is None: # check to see if we are in a notebook or not from ..viewer import in_notebook viewer = 'gl' if in_notebook(): viewer = 'notebook' if viewer == 'gl': # this imports pyglet, and will raise an ImportError # if pyglet is not available from ..viewer import SceneViewer return SceneViewer(self, **kwargs) elif viewer == 'notebook': from ..viewer import scene_to_notebook return scene_to_notebook(self, **kwargs) else: raise ValueError('viewer must be "gl", "notebook", or None') def __add__(self, other): """ Concatenate the current scene with another scene or mesh. Parameters ------------ other : trimesh.Scene, trimesh.Trimesh, trimesh.Path Other object to append into the result scene Returns ------------ appended : trimesh.Scene Scene with geometry from both scenes """ result = append_scenes([self, other], common=[self.graph.base_frame]) return result def split_scene(geometry, **kwargs): """ Given a geometry, list of geometries, or a Scene return them as a single Scene object. Parameters ---------- geometry : splittable Returns --------- scene: trimesh.Scene """ # already a scene, so return it if util.is_instance_named(geometry, 'Scene'): return geometry # a list of things if util.is_sequence(geometry): metadata = {} for g in geometry: try: metadata.update(g.metadata) except BaseException: continue return Scene(geometry, metadata=metadata) # a single geometry so we are going to split split = [] metadata = {} for g in util.make_sequence(geometry): split.extend(g.split(**kwargs)) metadata.update(g.metadata) # if there is only one geometry in the mesh # name it from the file name if len(split) == 1 and 'file_name' in metadata: split = {metadata['file_name']: split[0]} scene = Scene(split, metadata=metadata) return scene def append_scenes(iterable, common=['world']): """ Concatenate multiple scene objects into one scene. Parameters ------------- iterable : (n,) Trimesh or Scene Geometries that should be appended common : (n,) str Nodes that shouldn't be remapped Returns ------------ result : trimesh.Scene Scene containing all geometry """ if isinstance(iterable, Scene): return iterable # save geometry in dict geometry = {} # save transforms as edge tuples edges = [] # nodes which shouldn't be remapped common = set(common) # nodes which are consumed and need to be remapped consumed = set() def node_remap(node): """ Remap node to new name if necessary Parameters ------------- node : hashable Node name in original scene Returns ------------- name : hashable Node name in concatenated scene """ # if we've already remapped a node use it if node in map_node: return map_node[node] # if a node is consumed and isn't one of the nodes # we're going to hold common between scenes remap it if node not in common and node in consumed: name = str(node) + '-' + util.unique_id().upper() map_node[node] = name node = name # keep track of which nodes have been used # in the current scene current.add(node) return node # loop through every geometry for s in iterable: # allow Trimesh/Path2D geometry to be passed if hasattr(s, 'scene'): s = s.scene() # if we don't have a scene raise an exception if not isinstance(s, Scene): raise ValueError('{} is not a scene!'.format( type(s).__name__)) # remap geometries if they have been consumed map_geom = {} for k, v in s.geometry.items(): # if a geometry already exists add a UUID to the name if k in geometry: name = str(k) + '-' + util.unique_id().upper() else: name = k # store name mapping map_geom[k] = name # store geometry with new name geometry[name] = v # remap nodes and edges so duplicates won't # stomp all over each other map_node = {} # the nodes used in this scene current = set() for a, b, attr in s.graph.to_edgelist(): # remap node names from local names a, b = node_remap(a), node_remap(b) # remap geometry keys # if key is not in map_geom it means one of the scenes # referred to geometry that doesn't exist # rather than crash here we ignore it as the user # possibly intended to add in geometries back later if 'geometry' in attr and attr['geometry'] in map_geom: attr['geometry'] = map_geom[attr['geometry']] # save the new edge edges.append((a, b, attr)) # mark nodes from current scene as consumed consumed.update(current) # add all data to a new scene result = Scene() result.graph.from_edgelist(edges) result.geometry.update(geometry) return result