Compute normals correctly for plain geometries.

Fixes #77.

Author: jasongrout

js/src/jupyter-threejs.js

@@ -641,11 +641,18 @@ define(["jupyter-js-widgets", "underscore", "three", "ndarray"],
             }
             // TODO: faceVertexUvs
             geometry.elementsNeedUpdate = true;
-            geometry.uvsNeedUpdate = true;
+            if (!faceNormals) {
+                geometry.computeFaceNormals();
+            }
+            geometry.computeVertexNormals();
             geometry.normalsNeedUpdate = true;
+
+            geometry.computeLineDistances();
+            geometry.lineDistancesNeedUpdate = true;
+
+            geometry.uvsNeedUpdate = true;
             geometry.tangentsNeedUpdate = true;
             geometry.colorsNeedUpdate = true;
-            geometry.lineDistancesNeedUpdate = true;
             this.replace_obj(geometry);
         },
     });

pythreejs/pythreejs.py

@@ -19,6 +19,7 @@
 from math import pi, sqrt
 from .traits_numpy import array_serialization, shape_constraints
 from traittypes import Array
+import numpy as np
 
 def vector3(trait_type=CFloat, default=None, **kwargs):
     if default is None:
@@ -274,7 +275,7 @@ class PlainGeometry(Geometry):
     vertices = Array(dtype='float32').tag(sync=True, **array_serialization).valid(shape_constraints(None,3))
     faces = Array(dtype='uint32').tag(sync=True, **array_serialization).valid(shape_constraints(None,3))
     # list of [[v1_r,v1_g,v1_b], [v2_r,v2_g,v2_b], [v3_r,v3_g,v3_b]] for each face
-    faceColors = Array(dtype='float32').tag(sync=True, **array_serialization).valid(shape_constraints(None, 3, 3))
+    faceColors = Array(dtype='float32', default_value=np.empty(shape=(0,3,3), dtype='float32')).tag(sync=True, **array_serialization).valid(shape_constraints(None, 3, 3))
     #vertices = List(vector3(CFloat)).tag(sync=True)
     colors = List(Color).tag(sync=True)
     #faces = List(List(CFloat)).tag(sync=True)
@@ -290,7 +291,7 @@ class PlainBufferGeometry(Geometry):
 
     vertices = Array(dtype='float32').tag(sync=True, **array_serialization).valid(shape_constraints(None,3))
     faces = Array(dtype='uint32').tag(sync=True, **array_serialization).valid(shape_constraints(None,3))
-    colors = Array(dtype='float32', help="Vertex colors").tag(sync=True, **array_serialization).valid(shape_constraints(None,3))
+    colors = Array(dtype='float32', default_value=np.empty(shape=(0,3), dtype='float32'), help="Vertex colors").tag(sync=True, **array_serialization).valid(shape_constraints(None,3))
 
 class SphereGeometry(Geometry):
     _view_name = Unicode('SphereGeometryView').tag(sync=True)

pythreejs/traits_numpy.py

@@ -26,6 +26,8 @@ def array_from_json(value, widget):
 def shape_constraints(*args):
     """Example: shape_constraints(None,3) insists that the shape looks like (*,3)"""
     def validator(trait, value):
+        if trait.allow_none:
+            print(value)
         if len(value.shape) != len(args):
             raise TraitError('%s shape expected to have %s components, but got %s components'%(trait.name, len(args), (value, type(value))))
         for i, constraint in enumerate(args):