Intel® oneAPI Rendering Toolkit Release Notes

By Noga Collins, Olesya Andriyanova

Published:08/23/2019   Last Updated:12/04/2020

Intel® oneAPI Rendering Toolkit contains a set of rendering and ray-tracing libraries that are designed to help you transform big amounts of raw data into rich, realistic visuals and are optimized for the continuum of visualization needs. This page includes the release notes and issues associated with the toolkit. For software and hardware requirements, please refer to System Requirements page.

Intel® oneAPI Rendering Toolkit includes the following components:

Components distributed elsewhere:

Version History

Date Version Major Change Summary
December 2020 2021.1 2021.1 Release

Where to Find the Release

Please refer to the Intel® oneAPI Rendering Toolkit page for more information on how to acquire the package.

Intel® oneAPI Rendering Toolkit 2021.1

New in This Release

Note: Intel® Implicit SIMD Program Compiler (Intel® ISPC) 1.14.1 is the minimum version of Intel ISPC that is compatible with latest Intel oneAPI Rendering Toolkit components. Intel ISPC v1.14.1 use is strongly encouraged due to many quality of life compatibility benefits.

Intel® Embree 3.12.0

New Features
  • Added linear cone curve geometry support. In this mode a real geometric surface for curves with linear basis is rendered using capped cones. They are discontinuous at edge boundaries.
  • Enabled fast two level builder for instances when low quality build is requested.
Changes to Existing Features
  • Bugfix for BVH build when geometries got disabled.
  • Added EMBREE_BACKFACE_CULLING_CURVES cmake option. This allows for a cheaper round linear curve intersection when correct internal tracking and back hits are not required. The new cmake option defaults to OFF.
  • User geometries with invalid bounds with lower>upper in some dimension will be ignored.
  • Increased robustness for grid interpolation code and fixed returned out of range u/v coordinates for grid primitive.
  • Fixed handling of motion blur time range for sphere, discs, and oriented disc geometries.
  • Fixed missing model data in releases. 
  • Motion blur BVH nodes no longer store NaN values.
  • Ensure compatibility to newer versions of Intel® oneAPI Threading Building Blocks (oneTBB).
Unsupported or Discontinued Features

No features were deprecated.

Intel® OSPRay 2.4.0

New Features
  • The pathtracer optionally allows for alpha blending even if the background is seen through refractive objects like glass, by enabling backgroundRefraction 
  • Intel OSPRay now requires minimum Intel Open VKL v0.11.0 to bring the following improvements: 
    • Improved rendering performance of VDB volumes
    • Added support for configurable iterator depth via the maxIteratorDepth parameters for unstructured and particle volumes, improved performance
    • Added support for filter modes for structured volumes (regular and spherical)
  • Expose parameter horizonExtension of Sun-sky light, which extends the sky dome by stretching the horizon over the lower hemisphere
Changes to Existing Features
  • Optimize handling of geometry lights by the pathtracer
  • The optional denoiser image operation now respects frame cancellation, requiring Intel® Open Image Denoise with minimum version 1.2.3
  • Fixed normals of (transformed) isosurfaces
  • Robust calculation of normals of boxes geometry
  • Clipping geometry is now working correctly with map_maxDepth renderer parameter
  • Using materials in a renderer with a mismatched renderer_type no longer causes crashes while rendering
Unsupported or Discontinued Features

No features were deprecated.

Intel® Open Image Denoise 1.2.4

New Features
  • Added OIDN_API_NAMESPACE CMake option that allows to put all API functions inside a user-defined namespace
Changes to Existing Features
  • Fixed bug when TBB_USE_GLIBCXX_VERSION is defined
  • Fixed compile error when using an old compiler which does not support OpenMP SIMD
  • Export only necessary symbols on Linux and macOS
  • Added compatibility with oneTBB 2021. 
Unsupported or Discontinued Features

No features were deprecated.

Intel® Open Volume Kernel Library 0.11.0

New Features
  • Introduced API support for multi-attribute volumes, including APIs for sampling multiple attributes simultaneously 
    • Initially only structuredRegular and structuredSpherical volume types support multi-attribute data
  • Iterator APIs now work on sampler objects rather than volumes, supporting finer-grained configurability
  • Observers can now be created for both volume and sampler objects 
    • LeafNodeAccess observers must now be created on sampler objects
  • Log and error callbacks now support a user pointer
  • vdb volume interval iterators: 
    • Added support for elementary cell iteration when maxIteratorDepth is set to VKL_VDB_NUM_LEVELS-1
    • Up to 2x faster iteration
  • unstructured and particle volume interval iterators: 
    • Improved interior empty space skipping behavior
    • Added support for configurable iterator depth via the maxIteratorDepth parameter
  • Added support for filter modes in structuredRegular and structuredSpherical volumes
  • amr volumes now support method parameter on sampler objects
  • Added new interval_iterator_debug renderer in vklExamples to visualize interval iteration behavior
Changes to Existing Features
  • Hit iterator accuracy improvements for unstructured volumes
  • Fixed bugs in amr and vdb volume bounding box computations
  • Fixed bug in unstructured volume gradient computations near empty regions
  • Minimum Intel ISPC version is now v1.14.1
  • Integration with oneTBB 2021
Unsupported or Discontinued Features

No features were deprecated.

Intel® OSPRay Studio 0.5.0

New Features
  • New Component Offering
  • Intel OSPRay Studio is an open source and interactive visualization and ray tracing application that leverages Intel OSPRay as its core rendering engine. It can be used to load complex scenes requiring high fidelity rendering or very large scenes requiring supercomputing resources.
  • The main control structure is a scene graph which allows users to create an abstract scene in a generic tree hierarchy. Scenes can either be imported or created using scene graph nodes and structure support. The scenes can then be rendered either with a pathtracer or a scivis renderer.

Intel oneAPI Rendering Toolkit Utilities (rkUtil) 1.0.0

New Features
  • New Component Offering
  • Render Kit superbuild is the first utility to be offered to end users.
  • Render Kit superbuild will automatically download the entire recipe of Intel oneAPI Rendering Toolkit Source code, oneTBB binaries, Intel ISPC binaries and will build binaries for each component.



oneTBB dynamic runtime errors while using XCode*

Users may see issues in an XCode* IDE developer environment when setting up dynamic runtime search paths. Apple* System Integrity Protection may purge these paths.

Windows* OS:

Pre-built sample application runtime errors

Base Kit users may have dynamic runtime issues when running Intel oneAPI Rendering Toolkit prebuilt applications. For an environment variable script mitigation, try these steps when using Intel oneAPI Rendering Toolkit:

  • Start a new shell environment.
  • Run the oneAPI <oneapi_install_directory>\setvars.bat script in your shell.
  • Next, run the rkcommon vars.bat file. Find it here: <oneapi_install_directory>\rkcommon\latest\env\vars.bat

The goal with the above mitigation is for pre-compiled applications to use TBB 2020 Update 3 runtime libraries included with the Intel oneAPI Rendering Toolkit. This dependency is as opposed to the oneTBB 2021 branch included with the Base Kit.

Base Kit users who wish to run Base Kit only programs:

  • Start a new shell environment.
  • Run the oneAPI setvars.bat script in your shell.

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Product and Performance Information


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