Blender Git Loki

Merge branch 'blender-v2.92-release'

Fix T85722: missing updates adding modifiers via python

Was reported for Geometry Nodes Editor "New" button, but was true for
any modifier added via modifiers.new().

Now just add appropriate nofifier.

Maniphest Tasks: T85722

Differential Revision: https://developer.blender.org/D10450

Merge branch 'blender-v2.92-release'

Cleanup: Split COM_compositor into multiple functions.

Geometry Nodes: Expose material index attribute

The `material_index` attribute can adjust which material in the list
will be applied to each face of the mesh. There are two new things
about this attribute that haven't been exposed by the attribute API yet.
Each comes with limitations:
1. Integer data type: Most attribute nodes are currently written to use
float data types. This means that they can't write to this attribute
because they can't change the type of a built-in attribute.
2. Polygon domain: This is our first attribute using the polygon domain,
meaning until some of the interpolations are implemented, some
operations may not work as expected.

Currently the two nodes that work with this attribute are Attribute Fill
and Attribute Randomize.

Differential Revision: https://developer.blender.org/D10444

Cleanup: make local vars const.

Cleanup: Bundle static globals in struct

Cleanup: Comment style

Cleanup: Allocate Execution System on stack.

Cleanup: Make ChunkOrderHotspot a struct

Cleanup: Make ChunkOrder a struct.

Fix T85440: crash with displacement shaders and updating geometry in viewport

When primitive offsets change we need to rebuild or refit BVHs, however this
was also tagging other data as modified too late in the geometry update process.
Now ensure only the BVHs are updated.

Ref D10441

Cleanup: Use 'pygpu_' prefix in the cpython GPU module

`py_` prefix can be confused with the Python's own API's.

Cleanup: Fix typo error

Fix T80862: Small stroke opacity modulation is best done in the fragment shader

To avoid anti-aliasing artifacts on GPencil strokes that have a size smaller than 1 the thickness
is clamped and the opacity reduced. This was done in vertex shader but this had the side effect
of causing strokes that go from large to small to fade across their lengths.

**Solution**

The opacity modulation has now been moved to the fragment shader as advised by Cl�ment Foucault.

The strokeThickness that was passed to the shader was clamped to prevent it from being too small so an additional
unclamped thickness has been passed to the fragment to calculate the opacity modulation. Alternatively I could have chosen
strokeThickness and clampedThickness but I decided against renaming the variables in the current code.


Reviewed By: fclem

Differential Revision: https://developer.blender.org/D10438

Geometry Nodes: realize instances before deform modifier

This is a follow up commit for rB96da8e9ca302b8d879744.

Ref T85281.

Cleanup: Cycles, remove unneeded forward declaration

Cleanup: Cycles, use const reference in RenderBuffers::reset()

No functional changes. Allows to pass parameters as a const-reference
in the upcoming code.

Geometry Nodes: realize instances before passing geometry to constructive mesh modifier

Previously, when the output of a Geometry Nodes modifier would
contain instances, those could not be accessed by other existing
modifiers (e.g. the Array modifier). That is because those modifiers
don't know about instances.

Upcoming commits will improve an this in two ways:
* Also realize instances before deform modifiers.
* Convert a point cloud in the geometry to mesh vertices so that
they can be accessed as well.

Note, making instances real can result in loosing some information
that we do not support in Geometry Nodes yet. That includes some
special builtin attributes like bevel weights.

Ref T85281.

Differential Revision: https://developer.blender.org/D10432

Cycles: support accessing custom mesh attributes

This makes custom mesh attributes available in Cycles. Typically,
these attributes are generated by Geometry Nodes, but they can also
be created with a Python script.

* The `subdivision` code path is not yet supported.
* This does not make vertex weights and some other builtin attributes
available in Cycles, even though they are accesible in Geometry Nodes.
All attributes generated in Geometry Nodes should be accessible though.
* In some cases memory consumption could be removed by not storing all
attributes in floats. E.g. booleans and integer attributes for which
all values are within a certain range, could be stored in less than
4 bytes per element.

Differential Revision: https://developer.blender.org/D10210