Modulate VDB volume data with Ramps in Maya/Arnold

You can modulate the original VDB data channels with Ramp nodes:

  • Create an aiVolumeSampleFloat node
    Type the channel name you want to use as the driver in Channel (like density)
  • Create a Ramp node (delete the palce2dTexture node)
  • Connect the aiVolumeSampleFloat/OutValue to the Ramp node/V Coord
  • You can use the Ramp/OutColor output as an RGB color input in the aiStandardVolume shader (for example Scatter Color)
  • You can also use the Ramp/OutColorR output as single channel input in the aiStandardVolume shader (for example Density). So you can use the original ramp modulated density data as density input in the shader.

note:
You can also use the Remap Attribute feature in the aiVolumeSampleFloat node (the Bias is extremely useful).

Cheers, D

Ramp modulated density channel
Ramp modulated Scatter Color
The connections

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