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• There are two new optional controls for path-traced subsurface scattering - Attribute "trace" "int sssautobias" and "trace" "float sssbias". In the rare cases where the automatically computed bias for
  path-traced subsurface scattering needs tweaking, one can set "sssautobias" to 0 and "sssbias" to a desired value such as 1e-6. The default values are 1 for "sssautobias" and 1e-4 for "sssbias".

• Allow volumes to output their aovs via PxrTee.

Fixes

• Fix for bugs batched trace() with multiple shader groups in the hits.

Miscellaneous Changes

• improvements to light selection learning

• improve the behavior of denoised Marschner by changing how the albedo is calculated

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