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• Rendering with adaptive sampling after a breakpoint and resume took up to 20x longer than when uninterrupted; this was due to missing data in the checkpointing output file and has been fixed.
  

• Fixed a bug in OSL trace() that could happen when hitting multiple objects within a batch of rays.

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

• Fixed a bug that could result in bad texture derivatives at UDIM boundaries.

• Fixed offscreen decimation of dicing rate incorrect behavior with a custom ScreenWindow

• Fixed out-of-bounds vector access when a OSL spline is provided with only a single control point.

• Fixed incorrect default for the number of textures in PxrTileManifold and PxrRandomTextureManifold.

• Fixed rare holes in alpha channel due to missing ray hits on subdivision surfaces with intricate detail. (The holes were visible when looking at the alpha channel with gamma=0.)

• Fixed a bug where derivatives were uninitialized when fetching uniform attributes and options with OSL getattribute().

• PxrSwitch artifact when connecting a pattern to the index parameter.

• Fixed cases where texture3d() could lead to uninitialized values in derivatives.

• Fixed a bug where AreaScale of mesh lights was not properly updated during interactive updates.

• Added fix for shadow bump terminator index error in PxrDiffuse and PxrDisney
• Added fix for uninitialized direction in sampleMarschnerGLINTS()

• Optimized a pathological case for nested instancing on scene ingestion that can dramatically reduce render startup in certain cases.

• Fixed a bug that could cause intermittent crashes in non-deforming curves.
  

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