Blender Git Loki

Fix some smaller review comments, WIP changes trying to implement different arg parsing

Enable UMM addon by default.

Added logic to enable the omni addon by default on
startup and when initially setting user preferences.
This appears to be working, but is probably not the
officially sanctioned approach to set defaults, so
this must be investigated further.

Merge branch 'master' into refactor-idprop-ui-data

Cycles X: Initial support for the constant time rendering

Allows to limit render time, so that rendering will either happen
until all samples are finished, or the given time limit is reached.

Currently is only implemented for background and headless renders,
as those seems to benefit the most. In the viewport would still
like to investigate idea of keeping rendering until desired noise
floor is reached before adding extra settings there.

The usecases for the non-interactive (background, headless) renders
includes:

- Rendering a shot previews for movies.
- Ensuring some "bogus" frames do not stall the render farm.
- Allows to implement benchmark which will work reliable for both
very powerful and weak hardware configurations (as an example,
top-end GPUs and mobile GPUs) without requiring to wait forever
on a non-powerful hardware.

One of the tricky parts which is not solved in this version yet is
support of constant time rendering with multiple big tiles. However,
support of big tiles will be an addition on top of the existing code
as some sort of time limit would need to be enforced for every tile
(in other words, support of constant time render for multiple tiles
will be implemented on a higher level).

Differential Revision: https://developer.blender.org/D11526

Cycles X: Re-arrange sampling panel

More explicit separate viewport from render settings. Makes it easier
and more clear to add settings which are only for preview or only for
the final render.

| Before | After |
| {F10177700} | {F10177701} |

Among other thngs removed unused CYCLES_RENDER_PT_sampling_total.
Think better would be to call draw_samples_info for both viewport
and render samples.

Differential Revision: https://developer.blender.org/D11633

LineArt: Larger upper limit for smooth tolerance.

Merge branch 'master' into soc-2021-vse-strip-thumbnails

Fix Cycles X shadow catcher artifacts

Were caused by matte object appearing in the division process.

This change makes it so the matte object is removed from the
combined pass before division, which solves artifacts caused
by anti-aliasing (the matte "bleeds" into the shadow catcher
and produces artifacts around the rim).

Additionally made certain parts more explicit and better
documented.

Test file: {F10177353}

| Before | After |
| {F10177355} | {F10177358} |

Differential Revision: https://developer.blender.org/D11632

Merge branch 'master' into geometry-nodes-unnamed-attributes

Merge branch 'master' into soc-2021-uv-editor-improvements

Modernized for loop style.

Show ray direction input value socket by default.

Use distance subtype for the ray length input.

Remove unnecessary noop check in interpolator.

bli: generational_arena: better code styling

Fixed doc string.

Move AttributeInterpolator util class to bke.

Moved the utility class to BKE_mesh_sample.
Renamed it to MeshAttributeInterpolator to make clear that it works
on mesh attributes only.

Removed the hit_index output attribute.

This output contains the looptri indices on the hit mesh, which is not
very useful.

Cleanup. Forward declare SeqCollection, unused variable.

Changes based on review by Habib Gahbiche

Removed global variable FILE UPDATE COUNT, introduced a function
run_test().