Blender Git Loki

Cycles: fixed Embree transparent shadow ray intersection to terminate properly when opaque objects are hit

Cycles: Added Embree to Unix CMake files

Cycles: fixed Windows build with Embree

Cycles: fixed some warnings in embree integration

Cycles: prevented interactive rendering from crashing with Embree when objects are made invisible - RTCScenes now only get deleted by the top level BVH

Cycles: improved defaults for embree option, enable embree in the UI only when a CPU device is selected

Cycles: Added support for BVH refitting/dynamic meshes with embree

Cycles: improvements to hair rendering using embree

Cycles: embree hair now uses curve and not line segments, no more intersection filters for closest hit queries

Cycles: added memory and progress callbacks to embree

Cycles: Added volume support for embree

Cycles: Embree support for ribbon line segments and subsurface scattering

Cycles: Embree accelerator now supports instanced triangle meshes

Cycles: Progress with embree integration, still incomplete however

Cycles: more work on embree integration - triangle meshes now support deformation motion blur

Cycles: Laid some foundation for embree ray accelerator: flags, UI and CMake

Use material slot index instead of a direct Material pointer.

A Material pointer would be a nicer way to assign a hair material,
but unfortunately that does not work well with the context-based material
lookup of the node editor. There is no selection of an "active" modifier,
so the node editor will never display the material (unless it is placed
into a material stack as well).

Cleanup: rename edge -> edges

Merge branch 'blender2.8' into greasepencil-object

Cycles: Use ShaderEvalIntent more to pass flag, closures, and eval_task less

This makes it so that path_flag and max_closures are not passed to shader eval
functions, instead a limited number of ShaderEvalIntents are used. This also
removes the need for ShaderEvalTask in the mega kernel and simplifies the
code a bit.