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MaterialPhysicalVolume

Volume#

(MaterialPhysicalVolume)

  • Category: /Material/Physical
  • Default object name: volume

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Description#

A volume physical material

Attributes#

Name Type Description
Export Aovs bool Compute and write Aovs defined in the shading graph
Arbitrary Output Variables reference (AovStore) Set the list of extra channels to write to the image.
Light Path Expression Label string Set the material label in light path expressions.
Material Sample Count long Material sample count per pixel.
Volume Sampling Multiplier double Material volume sample count multiplier.
Russian Roulette double Amount of Russian roulette used on the material samples.
Roughness Noise Optimization double Noise reduction strategy along rough light path.
Volume Depth long Maximum volume depth.
Optical Mode long Select whether the optical properties of the volume are defined using the absorption-scattering, scattering-attenuation, or attenuation-albedo pair of parameters. Note that in the scattering-attenuation mode (Legacy mode - provided for compatibility purposes), the volume no longer obeys the physical law of energy conservation (i.e., the particles will scatter more light than they receive) whenever the value of the scattering parameter is greater than the value of the attenuation parameter (hence yielding a negative absorption and an albedo greater than one).
Absorption double[3] Set the relative absorption cross section of the volumetric particles.
Scattering double[3] Set the relative scattering cross section of the volumetric particles.
Attenuation double[3] Set the relative attenuation (absorption + scattering) cross section of the volumetric particles.
Albedo double[3] Set the reflectivity of the attenuating particles.
Emission double[3] Set the quantity of light emitted by particles. This adds a constant color on the whole volume and doesn't affect the transmission of light.
Density Multiplier double Multiply the density of the geometry by this value.
Forward Scattering double Control the intensity of the forward scattering. Use a negative value to obtain backward scattering and a null value to scatter the light in all directions with the same intensity.
Sampling Optimization double Allow to divide samples among overlapping volumes.