Fixed compas_ghpython is not importable in Rhino8

CHANGELOG.md

@@ -11,6 +11,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+* Fixed support for `compas_gpython` in Rhino 8 Grasshopper CPython components.
+
 ### Removed
 
 

src/compas/plugins.py

@@ -22,6 +22,8 @@
 import pkgutil
 import threading
 
+import compas
+
 __all__ = [
     "pluggable",
     "plugin",
@@ -33,6 +35,17 @@
     "PluginDefaultNotAvailableError",
 ]
 
+if compas.RHINO:
+    import System  # type: ignore  # pragma: no cover
+
+    DotNetException = System.Exception  # pragma: no cover
+else:
+
+    class DummyDotNetException(BaseException):
+        pass
+
+    DotNetException = DummyDotNetException
+
 
 class PluginNotInstalledError(Exception):
     """Exception raised when an extension point is invoked but no plugin is available."""
@@ -401,15 +414,15 @@ def try_import(self, module_name):
             If importable, it returns the imported module, otherwise ``None``.
         """
         module = None
-
         try:
             module = __import__(module_name, fromlist=["__name__"], level=0)
             self._cache[module_name] = True
 
         # There are two types of possible failure modes:
         # 1) cannot be imported, or
         # 2) is a python 3 module and we're in IPY, which causes a SyntaxError
-        except (ImportError, SyntaxError):
+        # 3) in Rhino8 we may get a nasty DotNet Exception when trying to import a module
+        except (ImportError, SyntaxError, DotNetException):
             self._cache[module_name] = False
 
         return module

src/compas_ghpython/__init__.py

@@ -11,9 +11,6 @@
 
 __version__ = "2.4.2"
 
-if compas.is_rhino():
-    from .utilities import *  # noqa: F401 F403
-
 __all__ = [
     "get_grasshopper_managedplugin_path",
     "get_grasshopper_library_path",

src/compas_ghpython/drawing.py

@@ -20,8 +20,8 @@
 from Rhino.Geometry import Vector3f
 
 from compas.geometry import centroid_points
+from compas.geometry import centroid_polygon
 from compas.itertools import pairwise
-from compas_rhino.drawing import _face_to_max_quad
 
 try:
     from Rhino.Geometry import MeshNgon
@@ -31,6 +31,17 @@
 TOL = sc.doc.ModelAbsoluteTolerance
 
 
+def _face_to_max_quad(points, face):
+    faces = []
+    c = len(points)
+    points.append(centroid_polygon(points))
+    for i in range(-1, len(face) - 1):
+        a = face[i]
+        b = face[i + 1]
+        faces.append([c, a, b, b])
+    return faces
+
+
 def draw_frame(frame):
     """Draw a frame."""
     pt = Point3d(*iter(frame.point))

src/compas_ghpython/scene/__init__.py

@@ -87,7 +87,7 @@ def register_scene_objects():
     register(VolMesh, VolMeshObject, context="Grasshopper")
     register(Brep, BrepObject, context="Grasshopper")
 
-    # print("GH SceneObjects registered.")
+    print("GH SceneObjects registered.")
 
 
 __all__ = [

src/compas_ghpython/scene/meshobject.py

@@ -4,7 +4,6 @@
 
 from compas.scene import MeshObject as BaseMeshObject
 from compas_rhino import conversions
-from compas_rhino.scene.helpers import ngon
 
 from .sceneobject import GHSceneObject
 
@@ -147,11 +146,21 @@ def draw_faces(self):
             for face in faces:
                 color = self.facecolor[face]  # type: ignore
                 vertices = [self.mesh.vertex_attributes(vertex, "xyz") for vertex in self.mesh.face_vertices(face)]  # type: ignore
-                facet = ngon(len(vertices))
+                facet = self._create_ngon(len(vertices))
 
                 if facet:
                     geometry = conversions.vertices_and_faces_to_rhino(vertices, [facet], color=color)
                     geometry.Transform(transformation)
                     meshes.append(geometry)
 
         return meshes
+
+    @staticmethod
+    def _create_ngon(vertex_count):
+        if vertex_count < 3:
+            return
+        if vertex_count == 3:
+            return [0, 1, 2]
+        if vertex_count == 4:
+            return [0, 1, 2, 3]
+        return list(range(vertex_count))

src/compas_ghpython/scene/volmeshobject.py

@@ -4,7 +4,6 @@
 
 from compas.scene import VolMeshObject as BaseVolMeshObject
 from compas_rhino import conversions
-from compas_rhino.scene.helpers import ngon
 
 from .sceneobject import GHSceneObject
 
@@ -84,7 +83,7 @@ def draw_faces(self):
         for face in faces:
             color = self.facecolor[face]
             vertices = [self.vertex_xyz[vertex] for vertex in self.volmesh.face_vertices(face)]
-            facet = ngon(len(vertices))
+            facet = self._create_ngon(len(vertices))
             if facet:
                 meshes.append(conversions.vertices_and_faces_to_rhino(vertices, [facet], color=color))
 
@@ -115,3 +114,13 @@ def draw_cells(self):
             meshes.append(mesh)
 
         return meshes
+
+    @staticmethod
+    def _create_ngon(vertex_count):
+        if vertex_count < 3:
+            return
+        if vertex_count == 3:
+            return [0, 1, 2]
+        if vertex_count == 4:
+            return [0, 1, 2, 3]
+        return list(range(vertex_count))

tests/compas/test_plugins.py

@@ -1,7 +1,7 @@
 from abc import abstractmethod
 
 import pytest
-
+import compas
 from compas.plugins import IncompletePluginImplError
 from compas.plugins import PluginValidator
 
@@ -36,3 +36,28 @@ def test_ensure_implementations_fails_with_incomplete_impl():
 
 def test_ensure_implementations_with_valid_impl():
     PluginValidator.ensure_implementations(CompleteImpl)
+
+
+def test_dot_net_exception_with_rhino():
+    if not compas.RHINO:
+        return
+
+    from compas.plugins import DotNetException
+
+    assert DotNetException is not None
+
+    import System
+
+    assert DotNetException == System.Exception
+
+
+def test_dot_net_exception_without_rhino():
+    if compas.RHINO:
+        return
+
+    from compas.plugins import DotNetException
+
+    assert DotNetException is not None
+    from compas.plugins import DummyDotNetException
+
+    assert DotNetException == DummyDotNetException