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Aggregate volumes are fully supported by the PxrPathTracer and PxrUnified integrators. As noted above, aggregate volumes are designed to be more efficient than the previous volume workflow in situations with tens or hundreds of overlapping volumes. This design also means that aggregate volumes are far less prone to issues that can arise when dealing with coincident geometry (such as coincident volume boundaries, or volumes coincident with surfaces).

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Aggregate volumes also offer several advantages that are not available to non-aggregate volumes. They support mipmapped volumes, which can potentially reduce memory consumption for overly detailed volumes, and prebaked acceleration information, which can greatly reduce time to first judgement for renders. Aggregate volumes may also have faster convergence in complex light transport scenarios, as the renderer/integrator is able to make global decisions about sampling with information about more volumes in the scene.

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