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| int geometry.instanceSkipIndex | A list of indices in to omit from the instance array. Used to prune out certain instances. |
| group geometry.arbitrary | While formatted as constant PrimVars, these attributes become user attributes in the renderer. There should be an element in the value and indexValue attributes for each instance in the instance array. |
See this instanceArray.katana file for a simple zip example (also available in RfK's Examples directory) for an example of how to set up an instance array from a point cloud.
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