• Improved performance for compact (but not robust) scenes.
• Added robust mode for motion blurred triangles and quads.
• Added fast dynamic mode for user geometries.
• Up to 20% faster BVH build performance on the second generation
  Intel® Xeon Phi™ processor codenamed Knights Landing.
• Improved quality of the spatial split builder.
• Improved performance for coherent streams of ray packets (SOA layout),
  e.g. for fast primary visibility.
• Various bug fixes in tessellation cache, quad-based spatial
  split builder, etc.