Using Volume Aggregates in Blender

Volume Aggregates Editor

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To create a volume aggregate, you can use the Volume Aggregate Editor, which can be accessed from the right click menu in the viewport:

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You can also select the volume you want from the viewport and then add it to the group, from the right click menu:

Integrator

To specify the global volume aggregate to the integrator, make sure an integrator node tree has been created (see Integrators in Blender), and then select the volume aggregate name in Volume Aggregate Name drop down list.

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