Volumes

Volumes are objects made of density, such as fire or clouds.

Note:

The rendering of volumes should not be confused with atmosphere_volume, which is a global effect.

Note:

Volumes can only receive indirect lighting from other emissive volumes when the volume_ray_depth is above 0.

Volume Formats

Rendering volumes with HtoA only works with OpenVDB files or VDB primtives.
You can also develop your own volume plugin with the new volume API.
It is also possible to render particles as volume.
You can also render polymeshes as volumes.

Volume Nodes

Arnold volume - Arnold volume object node.
standard_volume - Shader that defines the volume shading properties.
volume_sample_rgb and float - Shaders that sample a volume channel.

Render Quality

Several parameters affect the overall quality of volume rendering:

On the Arnold ROP: volume_diffuse_samples
On the Arnold ight: volume_samples
On the Arnold volume: step_size