• Added support for multi-segment motion blur for all primitive
  types.
• API support for stream of pointers to single rays (rtcIntersect1Mp and
  rtcOccluded1Mp)
• Improved BVH refitting performance for dynamic scenes.
• Improved high-quality mode for quads (added spatial split builder
  for quads)
• Faster dynamic scenes for triangle and quad-based meshes on AVX2
  enabled machines.
• Performance and correctness bugfix in optimization for streams of
  coherent (single) rays.
• Fixed large memory consumption (issue introduced in Embree
  v2.11.0). If you use Embree v2.11.0 please upgrade to Embree
  v2.12.0.
• Reduced memory consumption for dynamic scenes containing small meshes.
• Added support to start and affinitize TBB worker threads by passing
  "start_threads=1,set_affinity=1" to rtcNewDevice. These settings
  are recommended on systems with a high thread count.
• rtcInterpolate2 can now be called within a displacement shader.
• Added initial support for Microsoft's Parallel Pattern Library (PPL) as
  tasking system alternative (for optimial performance TBB is highly recommended).
• Updated to TBB 2017 which is released under the Apache v2.0
  license.
• Dropped support for Visual Studio 2012 Win32 compiler. Visual
  Studio 2012 x64 is still supported.