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• All RenderMan node versions have changed to 3.0. Scenes should automatically convert to using these new nodes on startup unless you have a custom OPcustomize setup. 
• Deprecate the combiner nodes. Display and Sample filters are now added via a multiparm on the ROP, and multiple light filters are directly linked to the light. 
• RenderMan errors are now warnings in Houdini
• Automatic conversion of PxrHSL, PxrVary, PxrSurface, PxrMix from old scenes to the new parameter names in RenderMan 24 rely on the 456.py script on houdini scene load rather than Houdini's opalias. This is to allow us to change parameter names and keep the old values. If you already have a 456 in your pipeline, you will need to add the update methods in order to convert those shaders.
• Improved user friendliness of Cryptomatte in RfH by renaming geometry nodes to use houdini node path. 
• Apply materials to instance points via instancer
• Use ptinstance on any obj node to instance rather than only the instance obj. 
• Improvements to material instances. 
• Added flush texture cache menu tool
• PxrDisney has been hidden in favor of the new PxrDisneyBsdf (PxrDisney deprecated)
• Batch renders now obey soho_autoheadlight parameter
• Velocity motion blur improvements

• Fix bug for colliding parameter names on pxrmaterialbuilder

• Curves rendering improvements
• Viewport light improvements (dome orientation, distant light intensity, cone angle indicators, ramp light filter)
• Use ptinstance on any obj node to instance rather than only the instance obj. 
• Improvements to material instances. 
• Add support for pre render and post render callbacks. 
• Acceleration motion blur.
• apply materials to alembic via shop_materialpath if material is already included in scene.
• fixed issue of incorrect transforms for OBJ_Blend and OBJ_Bone
• show dialog warnings for license failures. 
• deprecate PxrSeExpr, PxrDisney.

Changes in Solaris

• Added support for Pause and Resume rendering while in interactive mode
• Fixed a bug where for batch renders shutterOpen/Close weren't being correctly stashed in the context for use by deforming geometry
• Added baking options to the RenderMan LOP under the Rendering/Render tab
• Fixed a bug where PxrCryptomatte sample filter could pick up the wrong camera substitution for the <camera> variable in its filename
• Fixed a bug where vdb files with a first field not named density wouldn't render
• Fixed a bug that caused some incorrect sample times when more than 3 samples for deforming motion blur

• Fixed a hang that could arise when switching frames during interactive rendering

• Improved motion blur support

• Fixed a crash in hdPrman that could occur when running in the usdview that ships with Solaris if the camera was not created with Solaris and lacked certain attributes that we support for Solaris cameras

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