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Utilizing the functions of the KaBoom Box HDA is the recommended workflow for shading if the user would like to take advantage of VEX/VDB processes that are native to Houdini SOPs networks. It can also be a more desirable workflow for look-developing using the viewport. Caching the shading calculation data into a VDB can also save render time for high-resolution or data-heavy volumes.

Eugene Riecansky Section here will a walkthrough from Houdini to Maya for example might be useful for users