Validate index attribute on BufferGeometry

Author: vidartf

pythreejs/core/BufferAttribute.py

@@ -1,7 +1,4 @@
-import numpy as np
 from ipywidgets import register
-from traitlets import validate, TraitError, Undefined
-from ipydatawidgets import NDArrayWidget
 
 from .BufferAttribute_autogen import BufferAttribute as BaseBufferAttribute
 

pythreejs/geometries/PlainBufferGeometry.py

@@ -1,8 +1,12 @@
 
-from ipywidgets import register
+from ipywidgets import register, widget_serialization
+from traitlets import validate, TraitError
+from ipydatawidgets import NDArrayWidget
+
 from .PlainBufferGeometry_autogen import PlainBufferGeometry as PlainBufferGeometryBase
 
 
+
 @register
 class PlainBufferGeometry(PlainBufferGeometryBase):
 
@@ -12,5 +16,17 @@ def from_geometry(cls, geometry):
         """
         return cls(_ref_geometry=geometry)
 
+    @validate('attributes')
+    def validate(self, proposal):
+        value = proposal['value']
 
+        if 'index' in value:
+            # We treat index special, so we might as well do some checking:
+            idx = value['index']
+            array = idx.array if isinstance(idx, NDArrayWidget) else idx.array
+            if array.dtype.kind != 'u':
+                raise TraitError('Index attribute must have unsigned integer data')
+            if array.ndim != 1:
+                raise TraitError('Index attribute must be a flat array. Consider using array.ravel().')
 
+        return value