ArnoldVDB

Creates an external procedural for rendering VDB volumes in Arnold.

user

Container for user-defined plugs. Nodes should never make their own plugs here, so users are free to do as they wish.

out

The output scene.

enabled

The on/off state of the node. When it is off, the node outputs an empty scene.

name

The name of the object in the output scene.

sets

A list of sets to include the object in. The names should be separated by spaces.

transform

The transform applied to the object.

fileName

The name of the VDB file to be loaded.

Supported file extensions : vdb

grids

A space separated list of grids to be loaded and made available as channels in the volume shader.

velocityGrids

A space separated list of grids used to be used to generate motion blur. Should either contain a single vector grid or 3 float grids.

velocityScale

A scale factor applied to the velocity grids, to either increase or decrease motion blur.

stepSize

The ray marching step size. This should be small enough to capture the smallest details in the volume. Values which are too large will cause aliasing artifacts, and values which are too small will cause rendering to be excessively slow. The default value of 0 causes the size to be calculated automatically based on the resolution of the VDB file. The step scale can then be used to make relative adjustments on top of this automatic size.

stepScale

A multiplier applied to the step size. This is most useful when the step size is computed automatically. Typically stepScale would be increased above 1 to give improved render times when it is known that the VDB file doesn’t have a lot of fine detail at the voxel level - a value of 4 might be a good starting point for such a file.