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• Fixed a bug where scalar displacement was backwards when dicing an instanced master and the orientation is either "lh" or "rh".

• Fixed bug causing potential crash when using aggregate volumes.

• Fixed a bug where using alembic archives (AlembicProcPrim) with motion blur would crash on Windows.

• Fixed a potential issue with infinite lights in very large scenes.

• Fixed bug that could cause a crash when using a gprim with very many vertices and/or primvars.

• Fixed bug causing reduced thread efficiency and potential hangs when rendering many things with different grouping membership, enabled lights, or enabled lightfilters state.

• Fixed a potential crash when a hierarchical subdivision mesh specified an invalid face index in a face edit.

• Fixed bug causing a very small chance of crashing when rendering a scene containing both infinite and local lights.

• Some fixes for subsurface scattering with the PxrVCM (and PxrUPBP) integrator(s) that may have cause them to render black or with artifacts.

• Fixed potential for crash or extra memory usage when rendering a large polygon mesh having non-quad faces and __faceindex values for per-face textures.

• Fixed tile-shaped artifacts on materials with both subsurface and diffuse transmission.

• Added the correct attribute for importanceMultiplier to the PxrMeshLight

• Fix of incorrect normals of instanced NURBS patches with non-homogeneous control points. Speedup of ray tracing of some NURBS.

• In OSL, trace() and getmessage("trace") now work when hit objects are not shaded.

• Fixed a bug that could cause incorrect interpolation of primitive variables in some cases of coarsely tessellated displaced surfaces.

• Fixed a possible issue with alpha values on matte objects and volumes.
• Fixed a bilinear interpolation bug in the EvaluateAtLimitMultiple() call of the SubdivEval API

• Fixed a bug where OSL texture() shadeop would return random values on missing textures instead of the "missingcolor" and "missingalpha" or "fill" values.

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