Blender Git Loki

Fall back to single threaded preview creation if ID can't do it thread-safe

Make object preview generation thread-safe

When creating the preview, the object is now deep-copied so the preview
generation doesn't have to be done on the main thread, or block it.

There's a failing assert for objects with particle settings, I think the assert
needs to be corrected but I'll leave this aside for later. Disabled it for now.

Automatically refresh "Current File" repository when creating assets

It's confusing when this doesn't refresh, it's local data after all. It's not
entirely cheap to do, but is quite fast to do still. I don't think it will be
an issue if it's just done for creating/deleting assets.

Merge branch 'asset-metadata' into asset-browser

Fix crash loading some files after recent merge

Caused by badly resolved merge conflicts.

Merge branch 'asset-metadata' into asset-browser

Merge branch 'master' into asset-metadata

Merge branch 'asset-metadata' into asset-browser

Merge branch 'master' into asset-metadata

Merge branch 'asset-metadata' into asset-browser

Merge branch 'master' into asset-metadata

Operator to create asset catalogs (aka smart-filters)

A catalog at this stage is just a named item stored in a file's asset
repository meta-data.
With these changes one can create a named asset catalog that is written
to the file and can be read successfully.

Support storing asset repository data in files

Given that a repository can be built up from a single, or multiple
.blends, it's not clear where the repository data should live. It should
still be possible to easily share a .blend file to share assets,
including relevant meta-data that is not solely stored on the asset
level.
E.g. if you want to share a single pose library, that should be
doable by sharing a single .blend. So the .blend needs to have the pose
library meta-data, i.e. the name of the library and which poses belong
to it. The current design forsees that the Pose Library is implemented
as a "cataloge" (aka "smart-filter", to be determined). These should be
stored per asset category in the repository.

So this commit works towards the following design idea:
Each .blend file with assets can additionally store repository
meta-data. When reading a repository, we don't only read the asset
meta-data but also the repository meta-data in each .blend file. The
union over all the .blend files is the total repository meta-data the
asset browser can display.
That way each .blend file still is an isolated unit that doesn't
necessarily depend on the existence of other .blend files (or an index)
in the same repository.

This commit implements the storage framework of the repository meta-data.

I also added a temporary define to help spotting the related changes in
future.

Ensure custom asset repository names are unique

These names are used as identifiers for the UI, we have to ensure their
uniqueness.

Merge branch 'asset-metadata' into asset-browser

Merge branch 'master' into asset-metadata

Fix issues with browsing repository .blend file

The file selection in the Preferences wasn't working well at all. Should
now work fine.

Fix default asset repository not being added

Merge branch 'asset-metadata' into asset-browser

Fix compile error after last merge