Blender Git Loki

USD material importer comments.

Also updated to more descriptive function name.

Merge branch 'master' into geometry-nodes-attribute-search

Starting a prototype

Working circle fill types (not triangle fan)

Cycles: initial implemention of intersect_closest kernel

Cycles: initial implementation of generate_camera_rays kernel

Cycles: dummy implementation of background and surface to write something

Cleanup: mark KernelGlobals const in kernel, and use ccl_restrict in new code

Not sure if restrict will help performance in practice, but might as well
start marking this kind of stuff as we bring back kernel functionality.

Cycles: disable old CPU path tracing and bake kernels implementation

Build only the new integrator kernels, for easier refactoring of the code.

Merge branch 'master' into temp-gpencil-interpolate

Make the different weight paint code paths exclusive to each other

Before you could have the new sculpt symmetry code and the older weight
paint symmetry code active at the same time. This would lead to users
easily trashing their weigh paint data if they were not careful when
switching between modes.

Now the specific weight paint symmetry code is an exclusive toggle so
the user can't accidentally mirror strokes and vertex groups at the same
time. This also paves the way of supporting Y and Z symmetry in the
future for weight groups mirroring if we decide to add it in the future.
(As the UI part for it is done)

See https://developer.blender.org/D10426

Cleanup: use pragma once for all kernel headers

Previously some were using #ifdef and some not, now make it all consistent so
we can more easily include headers without worrying about duplication, especially
while we reorganize the kernel code.

- ghost fcurve drawing uses Show Extrapolation setting

Merge branch 'master' into temp-gpencil-interpolate

Cycles: Communicate path tracer result to the UI

The Session side is implemented similarly to the progressive refine.
There is some code duplication there, but this is a temporary code,
since the tile and render tile concepts will likely be eliminated.

Cycles: Refactor KernelFunctions class

- Rename it toKernelFunction with a comment which makes it explicit
that it is a single kernel, which picks up best microarchitecture
for the current configuration.

- Re-write initialization part, avoiding chain of code-wise if-else
mixed together with preprocessor.

Some further possibilities:

- Avoid preprocessor check, and rely on settings and function pointers
to pick up best kernel, avoiding preprocessor.

- Use string_view or something similar instead of `char*` to make
comparison more modern.

Cycles: Refactor kernel invocation

Use variadic template and make KernelFunction look like an actual
function call. This was an initial plan when the abstraction was
added, just was never implemented because C++11 was not a thing
back in those days.

Cycles: Move kernel functions to own container struct

Allows to localize initialization logic, have all kernels grouped
together. But what is more important, allows to share function
pointers with queue.

Cycles: Boiler plate for actual kernels invocation

Now the integrator kernels will be invoked by the path traces.

For now the path state is hard-coded to 1. Will be done properly
as one of the nearest future changes.

Another thing which needs to be changed in the nearest future is
the render buffer management. We really need to communicate it
to the BlenderSession to start seeing actual pixels!

GPencil: curve select more/less