Embree v3.2.4

• Fixed compile issues with ICC 2019.
• Released ZIP files for Windows are now provided in a version linked against Visual Studio 2013 and Visual Studio 2015.

Embree v3.2.3

• Fixed crash when using curves with RTC_SCENE_FLAG_DYNAMIC combined with RTC_BUILD_QUALITY_MEDIUM.

Embree v3.2.2

• Fixed intersection distance for unnormalized rays with line segments.
• Removed libmmd.dll dependency for release builds under Windows.
• Fixed detection of AppleClang compiler under MacOSX.

Embree v3.2.1

• Bugfix in flat mode for hermite curves.
• Added EMBREE_CURVE_SELF_INTERSECTION_AVOIDANCE_FACTOR cmake option to control self intersection avoidance for flat curves.
• Performance fix when instantiating motion blurred scenes. The application should best use two (or more) time steps for an instance that instantiates a motion blurred scene.
• Fixed AVX512 compile issue with GCC 6.1.1.
• Fixed performance issue with rtcGetGeometryUserData when used during rendering.
• Bugfix in length of derivatives for grid geometry.
• Added BVH8 support for motion blurred curves and lines. For some workloads this increases performance by up to 7%.
• Fixed rtcGetGeometryTransform to return the local to world transform.
• Fixed bug in multi segment motion blur that caused missing of perfectly axis aligned geometry.
• Reduced memory consumption of small scenes by 4x.
• Reduced temporal storage of grid builder.

Embree v2.17.5

• Improved watertightness of robust mode.
• Fixed floating point exception in static variable initialization.
• Fixed AVX512 compile issue with GCC 6.1.1.

Embree v3.2.0

• Improved watertightness of robust mode.
• Line segments, and other curves are now all contained in a single
  BVH which improves performance when these are both used in a scene.
• Performance improvement of up to 20% for line segments.
• Bugfix to Embree2 to Embree3 conversion script.
• Added support for Hermite curve basis.
• Semantics of normal buffer for normal oriented curves has changed to simplify usage. Please see documentation for details.
• Using GLFW and imgui in tutorials.
• Fixed floating point exception in static variable initialization.
• Fixed invalid memory access in rtcGetGeometryTransform for non-motion blur instances.
• Improved self intersection avoidance for flat curves. Transparency rays with tnear set to previous hit distance do not need curve radius based self intersection avoidance as same hit is calculated again. For this reason self intersection avoidance is now only applied to ray origin.

Embree v3.1.0

• Added new normal oriented curve primitive for ray tracing of grass-like structures.
• Added new grid primitive for ray tracing tessellated and displaced surfaces in very memory efficient manner.
• Fixed bug of ribbon curve intersector when derivative was zero.
• Installing all static libraries when EMBREE_STATIC_LIB is enabled.
• Added API functions to access topology of subdivision mesh.
• Reduced memory consumption of instances.
• Improved performance of instances by 8%.
• Reduced memory consumption of curves by up to 2x.
• Up to 5% higher performance on AVX-512 architectures.
• Added native support for multiple curve basis functions. Internal basis conversions are no longer performed, which saves additional memory when multiple bases are used.
• Fixed issue with non thread safe local static variable initialization in Visual Studio 2013.
• Bugfix in rtcSetNewGeometry. Vertex buffers did not get properly overallocated.
• Replaced ImageMagick with OpenImageIO in the tutorials.

Embree v2.17.4

• Fixed AVX512 compile issue with GCC 7.
• Fixed issue with non thread safe local static variable initialization in VS2013.
• Fixed bug in the 4 and 8-wide packet intersection of instances with multi-segment motion blur on AVX-512 architectures.
• Fixed bug in rtcOccluded4/8/16 when only AVX-512 ISA was enabled.

Embree v3.0.0

• Switched to a new version of the API which provides improved flexibility but is not backwards compatible. Please see "Upgrading from Embree 2 to Embree 3" section of documentation for upgrade instructions. In particular, we provide a python script that performs most of the transition work.
• User geometries inside an instanced scene and a top-level scene no longer need to handle instID field of ray differently. They both just need to copy the context.instID into the ray.instID field.
• Support for context filter functions that can get assigned to a ray query.
• User geometries can now invoke filter functions using the rtcFilterIntersection and rtcFilterOcclusion calls.
• Higher flexibility through specifying build quality per scene and geometry.
• Geometry normal uses commonly used right hand rule from now on.
• Added self intersection avoidance to ribbon curves and lines. Applications do not have to implement self intersections workarounds for these primitive types anymore.
• Added support for 4 billion primitives in a single scene.
• Removed RTC_MAX_USER_VERTEX_BUFFERS and RTC_MAX_INDEX_BUFFERS limitation.
• Reduced memory consumption by 192 bytes per instance.
• Fixed some performance issues on AVX-512 architectures.
• Individual Contributor License Agreement (ICLA) and Corporate Contributor License Agreement (CCLA) no longer required to contribute to the project.

Embree v2.17.3

• Fixed GCC compile warning in debug mode.
• Fixed bug of ribbon curve intersector when derivative was zero.
• Installing all static libraries when EMBREE_STATIC_LIB is enabled.