For those who don’t know the tool: RenderMan from Pixar is a production renderer used across VFX and animation. It integrates with basically all DCC apps and USD pipelines.
Pixar has released RenderMan 27.2, the latest update to its production rendering system. According to the official documentation and release notes, the update focuses on improvements to USD workflows, XPU rendering, and core stability. RenderMan is developed by Pixar and is used in feature animation and VFX production. The 27.2 release follows the established 27 series architecture.
USD and Hydra workflow updates
RenderMan 27.2 continues to refine its USD centric rendering path. USD serves as the backbone for scene descriptions in many production pipelines, and RenderMan’s Hydra delegate enables interactive and final-frame rendering of USD stages within host applications. The update includes adjustments to how USD stages are translated and synchronised. Changes affect the evaluation and propagation of attributes from USD primitives into RenderMan’s internal scene representation. This includes refinements to light, material and geometry handling when rendering directly from USD.
Behaviour between Hydra-driven rendering and traditional scene translation paths has been aligned in several areas. Parameter evaluation and state updates have been corrected to reduce discrepancies between USD and non-USD workflows. OpenPBR support is extended within USD contexts. OpenPBR is an open material model designed for renderer-agnostic material definition. RenderMan 27.2 improves the mapping and interpretation of OpenPBR parameters, ensuring more consistent shading results when using USD-defined materials.
Light handling in USD scenes has been refined, including updates to parameter interpretation and light linking behaviour. Attribute inheritance and override cases have also been corrected in specific scenarios.
XPU feature coverage expands
RenderMan XPU, Pixar’s hybrid CPU GPU rendering architecture, receives additional feature support in 27.2. XPU is designed to distribute rendering workloads across CPU and GPU devices in a single render session. In earlier 27.x builds, some shading nodes and features were restricted to RIS, the CPU based renderer. The 27.2 update brings further parity between RIS and XPU.
Additional shading nodes and material features are now supported in XPU. Parameter handling and default values have been aligned more closely with RIS, reducing behavioural differences between the two modes. Updates also affect integrator behaviour and light transport handling in XPU. Certain light types and rendering options now behave consistently across CPU and hybrid modes. Texture evaluation and displacement workflows have been corrected in XPU, addressing cases where results diverged from RIS. This includes fixes to shading artefacts and inconsistencies in displacement evaluation under specific configurations.
Shading system refinements
RenderMan 27.2 introduces updates across its shading and material system. Changes affect specific shader nodes, parameter ranges and default values. In several cases, adjustments were made to ensure consistent evaluation between RIS and XPU.
OpenPBR integration continues to evolve, with improved correspondence between OpenPBR inputs and RenderMan’s internal shading representation. This reduces mismatches when exchanging materials through USD based pipelines.
Layered material evaluation has been corrected in edge cases involving texture lookups and attribute overrides. Procedural shading nodes receive fixes addressing order of operations and attribute inheritance issues. Arbitrary Output Variables, or AOVs, are also affected. The update corrects output behaviour in certain configurations, ensuring that custom render passes produce the expected data for compositing workflows.
Geometry and motion updates
Geometry handling has been refined in 27.2. Subdivision surface evaluation has been corrected in specific cases, particularly when driven by USD scene data. Instancing behaviour and attribute propagation across instances have also been updated to ensure accurate rendering results.
Motion blur evaluation receives fixes addressing timing and interpolation of animated attributes. These corrections affect both geometry deformation and transformation blur under certain configurations. Displacement workflows have been adjusted, improving consistency in how displacement is evaluated across rendering modes. This reduces visible discrepancies between CPU and hybrid renders.
Volume rendering and lights
Volume rendering receives targeted corrections in sampling and shading behaviour. These address edge cases that previously resulted in artefacts or incorrect density evaluation in particular setups. Lighting workflows are refined in both USD and non USD contexts. Light parameter interpretation, linking and shadow behaviour have been corrected where inconsistencies were identified. These changes contribute to more predictable lighting results when switching between RIS and XPU or between traditional and USD based scene translation.
Incremental
RenderMan 27.2 is an incremental update focused on expanding USD and XPU coverage, aligning behaviour between rendering modes, and correcting shading, geometry and lighting edge cases. There are no architectural overhauls in this release. Instead, the emphasis is on feature parity, correctness and stability across established workflows.
Facilities relying on USD centric pipelines or actively deploying XPU will find broader feature support and fewer fallback scenarios. As always, new tools and innovations should be tested before use in production.
// RenderMan 27.2 documentation
// https://rmanwiki-27.pixar.com/space/REN27/726761480/RenderMan+27.2/
