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Rendering volumes in Katana is similar to rendering other geometry: you'll need a volume primitive and a volume shader. The RenderMan Volume primitive is created in Katana using the PrmanVolume node. For a simple homogeneous volume such as fog you'll just need to assign the PxrVolume shader to the PrmanVolume primitive. More complex shading can be built on top of a PxrPrimvar pattern wired to connect volume data into the volume shader. RenderMan's volume shader PxrVolume along the PxrPrimvar and other patterns, provide a complete volume workflow for either OpenVDB volume data or geometric volume primitives. For more details on RenderMan's volume primitives see the RenderMan Volume Documentation.

Currently PrmanVolume supports two types of volumes:

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