Blender Git Loki

Fix T56255: Crash w/ collection access from Python

Added a multithreaded variant of split ff bb

macOS Deps: use xcode 10.13 sdk

Merge branch 'fracture_modifier' into fracture_modifier-2.8

GP: Add Simplify Shader FX option

This option was missing when old VFX modifers were backported as Shader FX.

Convince Win32 harder to create non-resizeable window

GP: Fix Front z-depth display precision

The zdepth 0 was clipped and need 0.000001

PyAPI: Make skin modifier roots settable

This make the root flag writable using the Python API, using the
generic skin vertex flag setter function.

Reviewed By: Campbell Barton

Differential Revision: https://developer.blender.org/D3583

Fix horrible invalid mesh freeing in weightvg modifiers.

Comes from rB7661f8a65b. Found while checking on T55818, but not solving
that issue of course.

Cleanup LIB_ID_COPY_ flags a bit, add missing comment.

Merge branch 'master' into blender2.8

Fix T55012: Corruption editing screen keymap

Cleanup: unused vars

Cleanup: line length

Comment spammy debug prints

Fixed opti edge flip not nulling corrected face and add sanity opti checks

Fix T54915: Usercount of active action increases when editing things with COW enabled.

Just pass along the 'no user refcount' flag to animdata copy function.

GP: Add python api to create brush settings for grease pencil

Merge branch 'master' into blender2.8

Fix Cycles crash rendering mix of instanced and non-instanced volumes.