Blender Git Loki

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

# Conflicts:
# source/blender/blenkernel/BKE_node.h
# source/blender/nodes/CMakeLists.txt

removed decimate node and reformatting

Set default values for dissolve node

Split decimate into three different nodes.

Cleanup: Remove unused transform matrix from objects

This was the only reference to this matrix.

https://developer.blender.org/D11770

Geometry Nodes: Add mesh input warning to curve to mesh node

A point of confusion about this node is that it doesn't work on the
output of the mesh circle primitive node. This patch adds a warning to
help with that. This avoids adding a warning when the geometry set
input has no mesh.

Differential Revision: https://developer.blender.org/D11771

adaptive_cloth: tests: MeshIO: write DNA Mesh loose edges

adaptive_cloth: MeshIO: support line indices for write to DNA Mesh

Array Brush: BMesh duplication working

USD skel export minor cleanup.

Made get_armature_bone_names() static to USDArmatureWriter.

Build: upgrade NanoVDB library to latest revision

This includes improved handling of OpenVDB trees with inactive voxels,
which previously could throw an error.

Ref T89581, T88438

Cleanup: use template utility function to handle OpenVDB grid types in Cycles

Fix T89581: Cycles crash rendering some OpenVDB files with inactive voxels

Print an error message instead.

Cleanup: Further use of const when accessing evaluated mesh

Also resolve a warning from the previous commit. The next blocker to
using const is `BKE_mesh_wrapper_ensure_mdata`.

Fix Cycles X OIDN with adaptive sampling

The decision on whether to scale input buffer was wrong.
It was wrong from the beginning in the Cycles X branch,
but the bug got avoided by some other state set differently.

Cleanup: Use const mesh to ensure BVH and triangulation cache

As noted in a comment now, these functions only update a cache, so they
don't change the logical state of the mesh, which is "it will have the
data when necessary." Using a const argument will help const correctness
when accessing an object's evaluated mesh.

Cycles X: Multi-device re-balancing

This is an initial implementation which seems to give better
device utilization here when using two non-matched GPUs, as
well as multi-GPU and CPU.

General idea is to balance amount of work based on an
observed performance of devices, and "re-slice" the big tile.

Things which are known to be not final but considered a further
development:

- The balancing algorithm might need some tweaks for the
objective function and weight modification to converge to
the ideal balance quicker.

- The "re-slicing" might also be optimized memory-wise.

- Headless rendering needs to give few iterations of smaller
works to allow multi-device to settle down in the balance.

The balancing logic is in own little file, which simplifies
process of experiments.

Differential Revision: https://developer.blender.org/D11774

GPencil: Simplify point to render space function

USD skel export WIP.

Added function to query bone names from armature
objects, to be invoked by the skinned mesh writer
when creating skeleton binding properties.

Cleanup: Fix variable redeclaration warning