Blender Git Loki

Depsgraph: Cleanup, de-duplicate couple of utility functions

Depsgraph: Cleanup, remove unused untested functions

Depsgraph: Use dependency graph flush routines to update particle settings

Previously tagging particle settings for update will iterate over all objects and
all their particle system to see whether something needs an update or not. Now we
put ParticleSettings as an ID to the dependency graph, so tagging it for update
will nicely flush updates to all dependent particle systems.

Current downside of this is that due to limitation of flush routines it will cause
some extra particle system re-evaluation when it technically not needed, and what's
more annoying currently it will discard point caches more often.

However, this is a good and simple demonstration case to improve tagging/flushing
system to accommodate for such cases (similar issues happens with CoW and shading
components). So let's try to find some generic solution to the problem!

Depsgraph: Use explicit parameters eval operation code

This replaces usage of generic PLACEHOLDEWR with string lookup with more
explicit opcode. This should make it faster to build dependency graph by
avoiding string comparisons when it's not needed.

There should be no user measurable different.

Depsgraph: Add generic parameters evaluation operation code

Currently unused, but the idea is to use this code instead of placeholder
operation code followed by string comparison.

Depsgraph: Use more explicit naming for operation codes

This way it's better indication what group of operation codes things belongs to.

Despgraph: cleanup, make separation of opcodes strings more clear

Depsgraph: Use more explicit name for particle system evaluation opcode

Eevee: SSR: Add double buffer so we can read previous frame color.

Also add simple reprojection and screen fade to the SSR resolve pass.

Eevee: SSR: Make raymarch step bigger.

Add inverse filter options for modifiers

Merge branch 'blender2.8' into greasepencil-object

Enbale Random by default in Noise modifier

Fix (unreported) seldom crash when using previews in filebrowser.

Hopefully fix it actually, at least could not reproduce it anymore with
that changen, but Was already quite hard to trigger before.
We need a memory barrier at this allocation, otherwise it might happen
after preview gets added to done queue, so preview could end up being
freed twice, leading to crash.

Added orientation calculation. Normals are now flipped correctly.

WIP: Initial implementation of array modifier

Manipulators: use nearest manipulator

Add utility function to get the nearest hit

Fix T52116: Blender internal BVH build crash in degenerate cases.

Bugfix T-Intersection orientation out of order.

Merge branch 'master' into blender2.8