allow None context

Author: Licini

docs/api/compas.scene.rst

@@ -23,7 +23,6 @@ Classes
     GeometryObject
     MeshObject
     NetworkObject
-    NoSceneObjectContextError
     Scene
     SceneObject
     SceneObjectNotRegisteredError

src/compas/__init__.py

@@ -135,6 +135,7 @@
 
 __all_plugins__ = [
     "compas.geometry.booleans.booleans_shapely",
+    "compas.scene",
 ]
 
 

src/compas/scene/__init__.py

@@ -9,7 +9,6 @@
 from __future__ import division
 
 from .exceptions import SceneObjectNotRegisteredError
-from .exceptions import NoSceneObjectContextError
 from .sceneobject import SceneObject
 from .meshobject import MeshObject
 from .networkobject import NetworkObject
@@ -26,9 +25,23 @@
 from .scene import SceneObjectNode
 from .scene import SceneTree
 
+from compas.plugins import plugin
+from compas.geometry import Geometry
+from compas.datastructures import Mesh
+from compas.datastructures import Network
+from compas.datastructures import VolMesh
+
+
+@plugin(category="factories", pluggable_name="register_scene_objects")
+def register_scene_objects_base():
+    register(Geometry, GeometryObject, context=None)
+    register(Mesh, MeshObject, context=None)
+    register(Network, NetworkObject, context=None)
+    register(VolMesh, VolMeshObject, context=None)
+
+
 __all__ = [
     "SceneObjectNotRegisteredError",
-    "NoSceneObjectContextError",
     "SceneObject",
     "MeshObject",
     "NetworkObject",

src/compas/scene/context.py

@@ -5,7 +5,6 @@
 from compas.plugins import PluginValidator
 from compas.plugins import pluggable
 
-from .exceptions import NoSceneObjectContextError
 from .exceptions import SceneObjectNotRegisteredError
 
 ITEM_SCENEOBJECT = defaultdict(dict)
@@ -69,7 +68,7 @@ def is_viewer_open():
     return Scene.viewerinstance is not None
 
 
-def _detect_current_context():
+def detect_current_context():
     """Chooses an appropriate context depending on available contexts and open instances. with the following priority:
     1. Viewer
     2. Plotter
@@ -82,6 +81,10 @@ def _detect_current_context():
         Name of an available context, used as key in :attr:`SceneObject.ITEM_SCENEOBJECT`
 
     """
+
+    if not ITEM_SCENEOBJECT:
+        register_scene_objects()
+
     if is_viewer_open():
         return "Viewer"
     if compas.is_grasshopper():
@@ -93,12 +96,13 @@ def _detect_current_context():
     other_contexts = [v for v in ITEM_SCENEOBJECT.keys()]
     if other_contexts:
         return other_contexts[0]
-    raise NoSceneObjectContextError()
+
+    return None
 
 
 def _get_sceneobject_cls(data, **kwargs):
     # in any case user gets to override the choice
-    context_name = kwargs.get("context") or _detect_current_context()
+    context_name = kwargs.get("context") or detect_current_context()
 
     dtype = type(data)
     cls = None
@@ -122,9 +126,6 @@ def _get_sceneobject_cls(data, **kwargs):
 
 
 def get_sceneobject_cls(item, **kwargs):
-    if not ITEM_SCENEOBJECT:
-        register_scene_objects()
-
     if item is None:
         raise ValueError(
             "Cannot create a scene object for None. Please ensure you pass a instance of a supported class."

src/compas/scene/exceptions.py

@@ -5,14 +5,3 @@
 
 class SceneObjectNotRegisteredError(Exception):
     """Exception that is raised when no scene object is registered for a given data type."""
-
-
-class NoSceneObjectContextError(Exception):
-    """Exception that is raised when no scene object context is assigned is registered for a given data type."""
-
-    def __init__(self):
-        error_message = "No context defined."
-        error_message += "\n\nThis usually means that the script that you are running requires"
-        error_message += "\na CAD environment but it is being ran as a standalone script"
-        error_message += "\n(ie. from the command line or code editor)."
-        super(NoSceneObjectContextError, self).__init__(error_message)

src/compas/scene/geometryobject.py

@@ -52,3 +52,7 @@ def __init__(self, geometry, **kwargs):
         self.show_points = kwargs.get("show_points", False)
         self.show_lines = kwargs.get("show_lines", True)
         self.show_surfaces = kwargs.get("show_surfaces", True)
+
+    def draw(self):
+        """Draw the geometry. Implemented by child classes."""
+        raise NotImplementedError

src/compas/scene/meshobject.py

@@ -2,8 +2,6 @@
 from __future__ import absolute_import
 from __future__ import division
 
-from abc import abstractmethod
-
 from compas.geometry import transform_points
 from .sceneobject import SceneObject
 from .descriptors.colordict import ColorDictAttribute
@@ -99,7 +97,6 @@ def vertex_xyz(self):
     def vertex_xyz(self, vertex_xyz):
         self._vertex_xyz = vertex_xyz
 
-    @abstractmethod
     def draw_vertices(self, vertices=None, color=None, text=None):
         """Draw the vertices of the mesh.
 
@@ -124,7 +121,6 @@ def draw_vertices(self, vertices=None, color=None, text=None):
         """
         raise NotImplementedError
 
-    @abstractmethod
     def draw_edges(self, edges=None, color=None, text=None):
         """Draw the edges of the mesh.
 
@@ -149,7 +145,6 @@ def draw_edges(self, edges=None, color=None, text=None):
         """
         raise NotImplementedError
 
-    @abstractmethod
     def draw_faces(self, faces=None, color=None, text=None):
         """Draw the faces of the mesh.
 
@@ -188,6 +183,16 @@ def draw_mesh(self, *args, **kwargs):
         """
         return self.draw(*args, **kwargs)
 
+    def draw(self):
+        """draw the mesh.
+
+        Returns
+        -------
+        None
+
+        """
+        raise NotImplementedError
+
     def clear(self):
         """Clear all components of the mesh.
 

src/compas/scene/networkobject.py

@@ -2,8 +2,6 @@
 from __future__ import absolute_import
 from __future__ import division
 
-from abc import abstractmethod
-
 from compas.geometry import transform_points
 from .sceneobject import SceneObject
 from .descriptors.colordict import ColorDictAttribute
@@ -90,7 +88,6 @@ def node_xyz(self):
     def node_xyz(self, node_xyz):
         self._node_xyz = node_xyz
 
-    @abstractmethod
     def draw_nodes(self, nodes=None, color=None, text=None):
         """Draw the nodes of the network.
 
@@ -115,7 +112,6 @@ def draw_nodes(self, nodes=None, color=None, text=None):
         """
         raise NotImplementedError
 
-    @abstractmethod
     def draw_edges(self, edges=None, color=None, text=None):
         """Draw the edges of the network.
 
@@ -140,6 +136,10 @@ def draw_edges(self, edges=None, color=None, text=None):
         """
         raise NotImplementedError
 
+    def draw(self):
+        """Draw the network."""
+        raise NotImplementedError
+
     def clear_nodes(self):
         """Clear the nodes of the network.
 

src/compas/scene/scene.py

@@ -4,6 +4,7 @@
 
 from .context import clear
 from .context import redraw
+from .context import detect_current_context
 from .sceneobject import SceneObject
 
 
@@ -207,7 +208,7 @@ class Scene(Data):
     def __init__(self, name=None, context=None):
         super(Scene, self).__init__(name)
         self._tree = SceneTree("Scene")
-        self.context = context
+        self.context = context or detect_current_context()
 
     @property
     def data(self):
@@ -288,6 +289,10 @@ def clear_objects(self):
 
     def redraw(self):
         """Redraw the scene."""
+
+        if not self.context:
+            raise ValueError("No context detected.")
+
         self.clear_objects()
 
         drawn_objects = []

src/compas/scene/volmeshobject.py

@@ -2,8 +2,6 @@
 from __future__ import absolute_import
 from __future__ import division
 
-from abc import abstractmethod
-
 from compas.geometry import transform_points
 from .sceneobject import SceneObject
 from .descriptors.colordict import ColorDictAttribute
@@ -108,7 +106,6 @@ def vertex_xyz(self):
     def vertex_xyz(self, vertex_xyz):
         self._vertex_xyz = vertex_xyz
 
-    @abstractmethod
     def draw_vertices(self, vertices=None, color=None, text=None):
         """Draw the vertices of the mesh.
 
@@ -133,7 +130,6 @@ def draw_vertices(self, vertices=None, color=None, text=None):
         """
         raise NotImplementedError
 
-    @abstractmethod
     def draw_edges(self, edges=None, color=None, text=None):
         """Draw the edges of the mesh.
 
@@ -158,7 +154,6 @@ def draw_edges(self, edges=None, color=None, text=None):
         """
         raise NotImplementedError
 
-    @abstractmethod
     def draw_faces(self, faces=None, color=None, text=None):
         """Draw the faces of the mesh.
 
@@ -183,7 +178,6 @@ def draw_faces(self, faces=None, color=None, text=None):
         """
         raise NotImplementedError
 
-    @abstractmethod
     def draw_cells(self, cells=None, color=None, text=None):
         """Draw the cells of the mesh.
 
@@ -208,6 +202,10 @@ def draw_cells(self, cells=None, color=None, text=None):
         """
         raise NotImplementedError
 
+    def draw(self):
+        """Draw the volmesh."""
+        raise NotImplementedError
+
     def clear_vertices(self):
         """Clear the vertices of the mesh.