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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.

• The PxrPrimvar built-in names "curvature_u" and "curvature_v" for principal curvatures can now also be written "curvatureU" and "curvatureV". This is for forward compatibility with the OSL version of PxrPrimvar in RenderMan 24.

• The fix for correctly combining the two shadow exclusion subsets defined by Attribute "trace" "string shadowexcludesubset" and the "string shadowExcludeSubset" parameter is now extended to dome lights as well.

Fixes

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

• Fixed a bug that could return garbage derivatives on failed texture lookups from OSL.

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