[BUG FIX] Raise exception if trying to load PointCloud as Mesh. (#2042)

Author: duburcqa

genesis/__init__.py

@@ -411,7 +411,7 @@ def _custom_excepthook(exctype, value, tb):
         from pygel3d import graph, hmesh
     except OSError as e:
         # Import may fail because of missing system dependencies (libGLU.so.1).
-        # This is not blocking because it is only an issue for hybrig entities.
+        # This is not blocking because it is only an issue for hybrid entities.
         pass
 
     try:

genesis/engine/mesh.py

@@ -195,7 +195,7 @@ def copy(self):
         Copy the mesh.
         """
         return Mesh(
-            mesh=self._mesh.copy(include_cache=True),
+            mesh=self._mesh.copy(**(dict(include_cache=True) if isinstance(self._mesh, trimesh.Trimesh) else {})),
             surface=self._surface.copy(),
             uvs=self._uvs.copy() if self._uvs is not None else None,
             metadata=self._metadata.copy(),
@@ -221,7 +221,7 @@ def from_trimesh(
             surface.update_texture()
         else:
             surface = surface.copy()
-        mesh = mesh.copy(include_cache=True)
+        mesh = mesh.copy(**(dict(include_cache=True) if isinstance(mesh, trimesh.Trimesh) else {}))
 
         try:  # always parse uvs because roughness and normal map also need uvs
             uvs = mesh.visual.uv.copy()
@@ -234,9 +234,10 @@ def from_trimesh(
         color_factor = None
         opacity = 1.0
 
-        if mesh.visual.defined:
-            if mesh.visual.kind == "texture":
-                material = mesh.visual.material
+        visual = mesh.visual
+        if isinstance(visual, trimesh.visual.texture.TextureVisuals) and visual.defined:
+            if visual.kind == "texture":
+                material = visual.material
 
                 # TODO: Parsing PBR in obj or not
                 # trimesh from .obj file will never use PBR material, but that from .glb file will
@@ -267,12 +268,15 @@ def from_trimesh(
                         else:
                             color_factor = (*color_factor[:3], color_factor[3] * opacity)
                 else:
-                    gs.raise_exception()
-
+                    gs.raise_exception(f"Unsupported Trimesh material type '{type(material)}'.")
             else:
                 # TODO: support vertex/face colors in luisa
-                color_factor = tuple(np.array(mesh.visual.main_color, dtype=np.float32) / 255.0)
-
+                color_factor = tuple(np.array(visual.main_color, dtype=np.float32) / 255.0)
+        elif isinstance(visual, trimesh.visual.color.VertexColor) and visual.vertex_colors.size > 0:
+            color = np.unique(visual.vertex_colors, axis=0)
+            if len(color) > 1:
+                gs.raise_exception("Loading point clouds with heterogeneous colors is not supported.")
+            color_factor = tuple(np.array(color, dtype=np.float32) / 255.0)
         else:
             # use white color as default
             color_factor = (1.0, 1.0, 1.0, 1.0)
@@ -328,7 +332,7 @@ def from_attrs(cls, verts, faces, normals=None, surface=None, uvs=None, scale=No
     def from_morph_surface(cls, morph, surface=None):
         """
         Create a genesis.Mesh from morph and surface options.
-        If the morph is a Mesh morph (morphs.Mesh), it could contain multiple submeshes, so we return a list.
+        If the morph is a Mesh morph (morphs.Mesh), it could contain multiple sub-meshes, so we return a list.
         """
         if isinstance(morph, gs.options.morphs.Mesh):
             if morph.is_format(gs.options.morphs.MESH_FORMATS):
@@ -355,9 +359,7 @@ def from_morph_surface(cls, morph, surface=None):
                 assert all(isinstance(mesh, trimesh.Trimesh) for mesh in morph.files)
                 meshes = [mu.trimesh_to_mesh(mesh, morph.scale, surface) for mesh in morph.files]
             else:
-                gs.raise_exception(
-                    f"File type not supported (yet). Submit a feature request if you need this: {morph.file}."
-                )
+                gs.raise_exception(f"File type not supported: {morph.file}")
 
             return meshes
 

genesis/options/morphs.py

@@ -18,7 +18,7 @@
 
 URDF_FORMAT = ".urdf"
 MJCF_FORMAT = ".xml"
-MESH_FORMATS = (".obj", ".ply", ".stl")
+MESH_FORMATS = (".obj", ".stl")
 GLTF_FORMATS = (".glb", ".gltf")
 USD_FORMATS = (".usd", ".usda", ".usdc", ".usdz")
 

genesis/utils/mesh.py

@@ -473,8 +473,12 @@ def postprocess_collision_geoms(
 
 def parse_mesh_trimesh(path, group_by_material, scale, surface):
     meshes = []
-    for _, mesh in trimesh.load(path, force="scene", group_material=group_by_material, process=False).geometry.items():
-        meshes.append(gs.Mesh.from_trimesh(mesh=mesh, scale=scale, surface=surface, metadata={"mesh_path": path}))
+    scene = trimesh.load(path, force="scene", group_material=group_by_material, process=False)
+    for tmesh in scene.geometry.values():
+        if not isinstance(tmesh, trimesh.Trimesh):
+            gs.raise_exception(f"Mesh type not supported: {path}")
+        mesh = gs.Mesh.from_trimesh(mesh=tmesh, scale=scale, surface=surface, metadata={"mesh_path": path})
+        meshes.append(mesh)
     return meshes
 
 

tests/test_render.py

@@ -1149,7 +1149,7 @@ def test_render_planes(tmp_path, png_snapshot, renderer_type, renderer):
 @pytest.mark.required
 @pytest.mark.parametrize("renderer_type", [RENDERER_TYPE.RASTERIZER])
 @pytest.mark.skipif(not IS_INTERACTIVE_VIEWER_AVAILABLE, reason="Interactive viewer not supported on this platform.")
-def test_batch_deformable_render(tmp_path, monkeypatch, png_snapshot):
+def test_batch_deformable_render(monkeypatch, png_snapshot):
     CAM_RES = (640, 480)
 
     # Disable text rendering as it is messing up with pixel matching when using old CPU-based Mesa driver