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• Importomatic
• PrimitiveCreate
• Alembic_InAlembic_In_Prman
• UsdIn
• ScenegraphGeneratorSetup + ScenegraphGeneratorResolve
• LocationCreate
• LocationGenerate
• OpScript

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Which node you use depends on what you are doing and how the pipeline is setup at your studio.  Typically, you will A common workflow is to use an Importomatic node to bring in a set of Alembic files representing the geometry for your shot.  If your studio has a custom geometry format, your pipeline team has most likely written a plugin to Katana that can be referenced within the Importomatic node to bring in geometry.

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For volumes, we recommend to follow the example within your installation found here: plugins/Resources/PRMan21/Examples/katana_files/spotlight_PxrVolume.katana  Loading in a volume requires a combination of nodesyou use the PrmanVolume node.  This node sets up the attributes required to render vdb or box volumes.

Its all a bunch of attributes...

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