Blender Git Loki

Fix T81254: Incorrect calculation of EEVEE Transmittance Volumetrics

Regular rendering uses a custom blend mode, but render passes renders to
2 separate textures. This wasn't configured correctly inside the
fragment shaders. This patch adds a switch to configure the fragment
shader with the correct attachments.

Backport to Blender 2.83.

Reviewed By: Cl�ment Foucault

Differential Revision: https://developer.blender.org/D9038

Fix T81688: BPY_thread_save crashes with Python 3.9

Calling PyEval_ReleaseLock() was crashing with Python 3.9
because it accessed the NULL pointer set by PyThreadState_Swap().

This happened when calling ViewLayer.update() for example.

While the existing logic could be fixed by swapping the thread-state
back before calling PyEval_ReleaseLock(), this depends on functions
which are tagged to be removed by v4.0.

Replace use of deprecated functions by calling PyEval_SaveThread(),
instead of inlining the logic, using _PyThreadState_UncheckedGet()
to prevent Python aborting.

The call to PyEval_ThreadsInitialized has been removed
as threads are now initialized with Python.
This could be replaced with Py_IsInitialized() however it doesn't look
like this is necessary.

This is compatible with Python 3.7 & 3.9.

Fix T81520: Crash setting the Cycles device from Python

Fix T81288:Select Linked fails with multi-object edit mode

Changing options after using select-linked didn't work
when the object being selected wasn't the active object.

Fix T81854: crash when undoing switch between sculpt and edit mode.

The logic of `BKE_sculpt_update_object_for_edit` was not correct. such
low-level functions should typically never preform depsgraph evaluation
themselves, they should be able to rely on getting a fully evaluated
depsgraph and just get needed data from there.

Supporting that required fixing other broken code higher in the
callstack, namely:
* `ED_object_sculptmode_enter_ex` was freeing evaluated data, for no
valid reason it would seem.
* `sculpt_undosys_step_decode` was ensuring an evaluated depsgraph
**before** calling `ED_object_mode_generic_exit`, which would
invalidate a lot of evaluated data.

Note that it is fairly difficult to track down all code paths leading to
`BKE_sculpt_update_object_for_edit`, so there may be still cases where
this gets called with improperly evaluated depsgraph.

Reviewed By: sergey

Maniphest Tasks: T81854

Differential Revision: https://developer.blender.org/D9270

Fix T81421: "Saving As..." a blend file with a Script node file path filled with 1023 symbols crashes Blender.

Usual lack of protection against buffer overflows when manipulating
strings.

Also add some basic tests for `BLI_path_rel`.

Fix T81942 EEVEE: Reflection Plane glitch with low clip distances

This was happening because the raytrace was not even being performed
due to the tracing line being too small after frustum clipping.

Fix T81939: crash calling bmesh.utils.vert_separate()

Missing NULL check in bmesh_kernel_vert_separate.

Fix (studio-reported) Armature: bug in handling of custom bone transform.

This specific pose channel pointer was not handled at all during
rebuilding of poses, meaning that it could end up pointing at some freed
pchan.

PyAPI: unregister add-ons when exiting

This lets add-on authors avoid false positive leaks when exiting.
In particular GPUShaders's although it applies to any PyObject that
stores memory allocated by guarded-alloc.

While this does add overhead on exit, on my system it's
under 1/100th of a second with all addons enabled.

See: T71362

Fix T81633 Workbench: TAA never resolve when enabling both X-Ray and cavity

This was caused by a wrong flag equality check when in xray mode because
the xray mode was masking the effect option flags that are not supported
in this mode. This means the never passed and the TAA was reset before
every redraw, leading to infinite rendering.

Blender v2.83.9 beta

LineArt: comment fixes.

Cleanup: fix function names

Merge remote-tracking branch 'origin/master' into lanpr-under-gp

LineArt: Python formatting fix.

LineArt: Formatting.

LineArt: Move OP exec functions into lineart_ops.c

Merge remote-tracking branch 'origin/master' into lanpr-under-gp

Merge branch 'master' into geometry-nodes