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• XPU™ — Pixar’s hybrid CPU + GPU rendering technology is a next-generation rendering engine, rewritten for speed and efficiency on film production assets. This first phase of XPU is focused on accelerating look development for shading artists.  XPU is only available in the Commercial version of RenderMan
  
  

• MaterialX Lama — A state-of-the-art material layering system developed at Industrial Light & Magic introduces a modular approach to building material networks and includes recent R&D new work on dispersion and energy conservation
  
  

• Stylized Looks™ — Move beyond physically based shading and lighting into a world where you can easily create a variety of styles for your projects.  You can non-destructively control outlines, create sketch patterns, and develop a wide range of unique looks, including Anime, by using the same familiar toolset. Stylized Looks is available only in the Commercial version of RenderMan
  
  

• OpenColorIO — Robust support for the industry standard ACES color management system and other color spaces in all bridge products, including the interactive RenderMan Image Tool
  
  

• Live Statistics — Watch your rendering resource usage live, thanks to a completely redesigned statistics system that prioritizes interactivity and extensibility
  
  
• New Patterns — We are continually working to provide more artistic options for your look development. New with this release are production-proven technologies Hex Tiling Manifold and Phasor Noise
  
  
• Light Baking — Greatly enhance your real-time and VR rendering needs by baking lighting to 2D texture maps or Point Clouds   
  
  
• OSL Patterns — We have converted the great majority of C++ patterns to OSL. This conversion allows the sharing of code between RIS and XPU, which provides confidence that the renders from RenderMan XPU are representative of what you will see in RenderMan RIS. C++ patterns are still supported, but they will only work in RIS
  
  
• Better Sampling — Blue noise dithering results in a perceptually cleaner image sooner
  
  
• Updates to Artist Tools — Support for Autodesk’s Maya, Foundry’s Katana, and SideFX’s Houdini and Solaris (including support for LPEs and AOVs in Solaris). 
  
  
• Preset Browser — Now supports Presets for MaterialX Lama and Stylized Looks and ships with examples for both.
  
  

• RenderMan for Blender — And last but not least, a new plugin for cutting edge RenderMan features in the open source content creation tool. Rewritten to take full advantage of the architecture of version 24.
  

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• Shading
  
  • PxrUnified integrator is currently experimental as it does not yet support all the standard rendering features.
  • PxrSurface back diffuse color is not output to the albedo color AOV
  • <primstr:nameofvalue> substitution of data from a constant primvar or user attribute on an object for dynamic filename substitution is not yet working for the gettextureinfo() OSL call.
  • Using the ' . ' character in the handle for an OSL shader could cause unpredictable results during re-rendering.
• Performance:
  • OSL startup.  We have upgraded to OSL 1.10 for both RIS and XPU in RenderMan 24.  We have found that this upgrade (and its dependencies) have slowed down time to start up for some scenes.

  • Volume integration with patterns.  Because of the switch from C++ to OSL patterns and the sensitivity of volume integration to pattern execution, there are performance regressions with volumes in RenderMan 24 compared to RenderMan 23 that remain to be addressed. There are also memory increases that remain to be addressed.  This is most noticeable when the volume density is connected to a pattern (e.g. PxrPrimVar); the performance regression can be avoided by avoiding a pattern connection if possible.

• Interactive instrumentation/statistics:
  • Bridge product (Maya, Katana, Houdini, Blender) initial integrations are available, but are turned off by default.  Artists can turn on the statistics through the buttons in the UI.
  • Web browser integration is still to come and is now likely to arrive in a future version of RenderMan.
• General rendering
  • Load on demand procedurals are not supported anymore, all procedurals are now loaded immediately
  • We do not read point data from OpenVDB files
  • Per-Instance baking is not supported, only the reference instance.
  • 3d baking: no direct bake-to-ptex support.
  • PxrBakePointCloud cannot directly render ptex.
  • Sample/Display filter plug-ins do not have access to lighting services for light dependent effects, e.g. lens flare.
  • Adding new mesh light on existing geometry during IPR results in double geometry.
  • Motion blurred polygons do not motion blur normals when deformed. Use Subdivision meshes instead.
  • When attempting to access an array primvar, you must first check the size of the array primvar and allocate the appropriate space. Not doing so may lead to a crash.
  • Points and curves cannot be used as geometric lights.
  • Analytical lights placed inside volumes may yield artifacts when made visible to the camera. As a work around, the light camera visibility should be turned off, and a geometry with a similar shape should be used (visible to camera, invisible to transmission and indirect rays), with the proper emissive bxdf.
  • Indirect Path Guiding in the PxrUnified integrator causes a crash
• Bridge Products:
  • RfH: Soloing MaterialX Lama nodes in complex shading networks can give incorrect result

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