Add calls to `BKE_callback_global_init()` and `BKE_callback_global_finalize()`
to ensure unit tests mimick Blender (and don't trip the assertions added
in rBbeea601e7253).
No functional changes to Blender.
No longer save asset catalogs on blendfile save. Instead:
- extend the confirmation prompt for unsaved changes to show unsaved
catalogs.
- In the confirmation prompt, make catalog saving explicit & optional,
just like we do it for external images. {F10881736}
- In the Asset Browser catalog tree, show an operator icon to save the
catalogs to disk. It's grayed out if there are no changes to save, or
if the .blend wasn't saved yet (required to know where to save the
catalog definitions to). {F10881743}
Much of the work was done by @Severin and reviewed by me, then we
swapped roles.
Reviewed By: Severin
Differential Revision: https://developer.blender.org/D12796
Add `blender::bke::AssetLibraryService` class that acts like a
blendfile-scoped singleton. It's allocated upon the first call to
`BKE_asset_library_load` and destroyed in the LOAD-PRE handler.
The `AssetLibraryService` ensures that edits to asset catalogs are not
lost when the asset browser editor closes (or even reloads). Instead,
the `AssetLibrary` pointers it owns are kept around as long as the blend
file is open.
Reviewed By: Severin
Maniphest Tasks: T92151
Differential Revision: https://developer.blender.org/D12885
So far we have used `std::string` for asset catalog paths. Some
operations are better described on a dedicated class for this, though.
This commits switches catalog paths from using `std::string` to a
dedicated `blender::bke::AssetCatalogPath` class.
The `using CatalogPath = AssetCatalogPath` alias is still there, and
will be removed in a following cleanup commit.
New `AssetCatalogPath` code reviewed by @severin in D12710.
Catalogs work like directories on disk (without hard-/symlinks), in that
an asset is only contained in one catalog.
See T90066 for design considerations.
#### Known Limitations
Only a single catalog definition file (CDF), is supported, at
`${ASSET_LIBRARY_ROOT}/blender_assets.cats.txt`. In the future this is
to be expanded to support arbitrary CDFs (like one per blend file, one
per subdirectory, etc.).
The current implementation is based on the asset browser, which in
practice means that the asset browser owns the `AssetCatalogService`
instance for the selected asset library. In the future these instances
will be accessible via a less UI-bound asset system.
The UI is still very rudimentary, only showing the catalog ID for the
currently selected asset. Most notably, the loaded catalogs are not
shown yet. The UI is being implemented and will be merged soon.
#### Catalog Identifiers
Catalogs are internally identified by UUID. In older designs this was a
human-readable name, which has the problem that it has to be kept in
sync with its semantics (so when renaming a catalog from X to Y, the
UUID can be kept the same).
Since UUIDs don't communicate any human-readable information, the
mapping from catalog UUID to its path (stored in the Catalog Definition
File, CDF) is critical for understanding which asset is stored in which
human-readable catalog. To make this less critical, and to allow manual
data reconstruction after a CDF is lost/corrupted, each catalog also has
a "simple name" that's stored along with the UUID. This is also stored
on each asset, next to the catalog UUID.
#### Writing to Disk
Before saving asset catalogs to disk, the to-be-overwritten file gets
inspected. Any new catalogs that are found thre are loaded to memory
before writing the catalogs back to disk:
- Changed catalog path: in-memory data wins
- Catalogs deleted on disk: they are recreated based on in-memory data
- Catalogs deleted in memory: deleted on disk as well
- New catalogs on disk: are loaded and thus survive the overwriting
#### Tree Design
This implements the initial tree structure to load catalogs into. See
T90608, and the basic design in T90066.
Reviewed By: Severin
Maniphest Tasks: T91552
Differential Revision: https://developer.blender.org/D12589
