Blender Git Loki

Merge branch 'master' into blender2.8

# Conflicts:
# source/blender/alembic/intern/abc_exporter.cc
# source/blender/alembic/intern/abc_exporter.h
# source/blender/alembic/intern/alembic_capi.cc
# tests/gtests/alembic/abc_export_test.cc

Alembic: exporting MetaBalls as mesh

- Only basis balls are exported, as they represent the resulting mesh.
As a result the mesh is written to Alembic using the name of the basis
ball.
- MetaBalls are converted to a mesh on every frame, then an
AbcMeshWriter is used to write that mesh to Alembic.

Merge branch 'master' into blender2.8

BMesh: use heap update for dissolve-decimate

Include file for DNA_DEPRECATED macro

Alembic import: fixed mesh corruption when changing topology

When the mesh changed topology but kept the vertex count the same, it would
result in a corrupt mesh. By checking the face & loop counts too, this has
become less likely.

I've checked IPolyMeshSchema::isConstant(), but it returns true even when
we see that the mesh changed topology.

BLI_heap: add validation check, improve tests

Also minor readability changes, avoid running both heap_up/down
gives minor speedup too.

Curve Fitting: heap reinsertion optimization

Cleanup: move docs out of header

Cleanup: const args

BLI_heap: minor changes to the API

Recent addition of 'reinsert' didn't match logic for ghash API.

Rename to BLI_heap_node_value_update,
also add BLI_heap_insert_or_update since it's a common operation.

Use BLI_heap_reinsert for decimate and beautify

Improves performance for high poly meshes,
~70% faster for decimate, only ~10% for beautify.

BLI_hash: add BLI_heap_reinsert

Allows avoiding remove/insert calls.

GTest: initial BLI_heap test

Fix T53185: After rendering an animation (Ctrl-F12), pressing F12 no longer renders single frames only

BLI_array_store: correct hashing single bytes

The single byte version of hash_data was casting from unsigned char
instead of signed.

This didn't cause any errors since the result of each aren't compared.
Even so, better keep them matching.

Cleanup: use uint type in BLI

Eevee: Volumetric: Fix Sun lamps not working.

Eevee: Unlock volumetric shader nodes.

Eevee: Make Smoke sim panel visible with EEVEE