Volume aggregates Aggregate volumes are a new technique allowing you to render overlapping volumes more efficiently and lower the time to first pixel. It also allows PxrSurface to use a heterogeneous volume in its interior integrator.
Aggregates rendering requires a specific setup in maya.
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Density Rolloff: Remap density to make less dense areas wispier or denser.
PxrSurface Interior Aggregate Volume
PxrSurface allows you to bind an aggregate volume set to its interior integrator, to render cloudy water, gemstones, etc.