Embree v4.3.3

• Added RTCError RTC_ERROR_LEVEL_ZERO_RAYTRACING_SUPPORT_MISSING which can indicate a GPU driver that is too old or not installed properly.
• Added the API function rtcGetDeviceLastErrorMessage to query additional information about the last RTCError returned by rtcGetDeviceError. This can be used in case device creation failed and a rtcErrorFunction could not be set up for this purpose.
• Added the API function rtcGetErrorString which returns a string representation of a given RTCError error code. This is purely meant for convenient error information reporting on the user application side.
• Performance improvements on GPU for the one level instancing case (RTC_MAX_INSTANCE_LEVEL_COUNT 1).
• Reduced the number of unneccessary GPU-CPU USM back-migrations which can increase build performance for scene with many instances on GPU.
• Started adding public CI tests for streamlining integration of external pull requests.
• Work-around for problem with unsigned Windows binaries.

Embree v4.3.2

• Embree now uses level zero raytracing extension to build BVH which enables forward-compatibility. On Linux, the package intel-level-zero-gpu-raytracing has to be installed in addition to the other packages listed here https://dgpu-docs.intel.com/.
• MacOS universal binary compilation now works.
• Some bugfixes for AVX512 on MacOS x86 machines.
• Known issue: It is recommended to run Embree on Intel® Data Center GPU Max Series (e.g. Intel® Data Center GPU Max 1550) with the following environment settings: NEOReadDebugKeys=1 UseKmdMigration=0
• Known issue: ISPC version of tutorials will not successfully build with MacOS universal binary compilation.

Embree v4.3.1

• Add missing EMBREE_GEOMETRY types to embree-config.cmake
• User defined thread count now takes precedence for internal task scheduler
• Fixed static linking issue with ze_wrapper library
• Better error reporting for SYCL platform and driver problems in embree_info and tutorial apps.
• Patch to glfw source is not applied by default anymore.
• Known issue: Running Embree on Intel® Data Center GPU Max Series with 2 tiles (e.g. Intel® Data Center GPU Max 1550) requires setting the environment variable ZE_FLAT_DEVICE_HIERARCHY=COMPOSITE.
• Known issue: Embree build using Apple Clang 15 and ARM support (via the SEE2NEON library) may cause "EXEC_BAD_INSTRUCTION" runtime exceptions. Please use Apple Clang <= 14 on macOS.

Embree v4.3.0

• Added instance array primitive for reducing memony requirements in scenes
  with large amounts of similar instances.
• Properly checks driver if L0 RTAS extension can get loaded.
• Added varying version of rtcGetGeometryTransform for ISPC.
• Fixed signature of RTCMemoryMonitorFunction for ISPC.
• Add support for ARM64 Windows platform in CMake.

Embree v4.2.0

• SYCL version of Embree with GPU support is no longer in beta phase.
• Improved BVH build performance on many core machines for applications that oversubscribe threads.
• Added rtcGetGeometryTransformFromScene API function that can get used inside SYCL kernels.
• No longer linking to ze_loader in SYCL mode to avoid Intel(R) oneAPI Level Zero dependency for CPU rendering.
• Releasing test package to test Embree.

Embree v4.1.0

• Added support for Intel® Data Center GPU Max Series.
• Added ARM64 Linux support.
• Added EMBREE_BACKFACE_CULLING_SPHERES cmake option. The new cmake option defaults to OFF.

Embree v4.0.1 Release

• Improved performance for Tiger Lake, Comet Lake, Cannon Lake, Kaby Lake, and Skylake client CPUs by using 256 bit SIMD instructions by default.
• Fixed broken motion blur of RTC_GEOMETRY_TYPE_ROUND_LINEAR_CURVE geometry type.
• Fixed bvh build retry issue for TBB 2020.3
• Added support for Intel® Data Center GPU Flex Series
• Fixed issue on systems without a SYCL platform.

Embree v4.0.0 Release

• This Embree release adds support for Intel® Arc™ GPUs through SYCL.
• The SYCL support of Embree is in beta phase. Current functionality, quality,
  and GPU performance may not reflect that of the final product. Please read the
  documentation section "Embree SYCL Known Issues" for known limitations.
• Embree CPU support in this release as at Gold level, incorporating the same quality
  and performance as previous releases.
• A small number of API changes were required to get optimal experience and
  performance on the CPU and GPU. See documentation section "Upgrading from Embree 3 to
  Embree 4" for details.
• rtcIntersect and rtcOccluded function arguments changed slightly.
• RTCIntersectContext is renamed to RTCRayQuery context and most members moved to
  new RTCIntersectArguments and RTCOccludedArguments structures.
• rtcFilterIntersection and rtcFilterOcclusion API calls got replaced by
  rtcInvokeIntersectFilterFromGeometry and rtcInvokeOccludedFilterFromGeometry API calls.
• rtcSetGeometryEnableFilterFunctionFromArguments enables argument filter functions for some geometry.
• RTC_RAY_QUERY_FLAG_INVOKE_ARGUMENT_FILTER ray query flag enables argument filter functions for each geometry.
• User geometry callbacks have to return if a valid hit was found.
• Ray masking is enabled by default now as required by most users.
• The default ray mask for geometries got changed from 0xFFFFFFFF to 0x1.
• Removed ray stream API as rarely used with minimal performance benefits over packet tracing.
• Introduced rtcForwardIntersect/rtcForwardOccluded API calls to trace tail recursive rays from user geometry callback.
• The rtcGetGeometryUserDataFromScene API call got added to be used in SYCL code.
• Added support for user geometry callback function pointer passed through ray query context
• Feature flags enable reducing code complexity for optimal performance on the GPU.
• Fixed compilation issues for ARM AArch64 processor under Linux.
• Setting default frequency level to SIMD256 for ARM on all platforms.
  This allows using double pumped NEON execution by enabling EMBREE_ISA_NEON2X in cmake under Linux.
• Fixed missing end caps of motion blurred line segments.
• EMBREE_ISPC_SUPPORT is turned OFF by default.
• Embree drops support of the deprecated Intel(R) Compiler. It is replaced by
  the Intel(R) oneAPI DPC++/C++ Compiler on Windows and Linux and the
  Intel(R) C++ Classic Compiler on MacOS (latest tested versions is 2023.0.0).

Embree v3.13.5 Release

• Fixed bug in bounding flat Catmull Rom curves of subdivision level 4.
• Improved self intersection avoidance for RTC_GEOMETRY_TYPE_DISC_POINT geometry type. Intersections are skipped if the ray origin lies inside the sphere defined by the point primitive. Self intersection avoidance can get disabled at compile time using the EMBREE_DISC_POINT_SELF_INTERSECTION_AVOIDANCE cmake option.
• Fixed spatial splitting for non-planar quads.

Embree v3.13.4 Release

• Using 8-wide BVH and double pumped NEON instructions on Apple M1 gives 8% performance boost.
• Fixed binning related crash in SAH BVH builder.
• Added EMBREE_TBB_COMPONENT cmake option to define the component/library name of Intel® TBB (default: tbb).
• Embree supports now Intel® oneAPI DPC++/C++ Compiler 2022.0.0