Blender Git Loki

Cleanup: fix warning -Wparentheses

GPencil: Select visible frame for preview image

The datablock must be in a frame inside the range to get a visible thumbnail.

Fix build warnings

Merge branch 'master' into soc-2021-porting-modifiers-to-nodes-merge-by-distance

# Conflicts:
# source/blender/modifiers/intern/MOD_weld.c

changes based on review by Hans Goudey (HooglyBoogly)

Merge branch 'master' into soc-2021-porting-modifiers-to-nodes-remesh-blocks

Merge branch 'master' into xr-controller-support

XR: Use dynamic arrays for eye, controller data

Makes API/functionality more adaptable to different systems.

XR: Move controller batch creation to draw func

Ensures that a valid GPU context is available during batch creation,
which fixes potential access violation issues.

Update with changes from master

36c0649d32aa, c41b93bda532

USD import: don't check for cache usdz extension.

Removed check for .usdz extension in logic to
determine cachfile type.

USD Import: removed unused variable.

Merge branch 'master' into soc-2021-curves

USD import: use pointers for out parameters.

Changed return parameter types from references to
pointers, to improve code readability, per suggestion
from Sybren.

UI: Do not abbreviate/shorten wording

Abbreviations are harder to read and understand thus it is best to be direct.
For example without understanding and context it is hard to know exactly what "Len" means.

USD import: get_opacity_threshold() function.

Moved the opacity threshold query logic out of the
needs_blend() function to a new get_opacity_threshold()
function, for readability.

GTest: Use INC/INC_SYS for Libmv/OSD tests

This change transitions libmv/osd tests to our
blender_add_test_executable macro that explicitly
takes the include directories as a parameter.

This is in preparation for future clean-up of
global include directories.

Differential Revision: https://developer.blender.org/D12012
Reviewed By: sergey

Add 'projection' option for volume-preserving smoothing to
smooth corrective modifier

Cleanup: replace defines with static const in walk/fly operators.

No functional changes.

Supply tablet data with