Asset Browser: Support dragging assets into catalogs

With this it is possible to select any number of assets in the Asset
Browser and drag them into catalogs. The assets will be moved to that
catalog then. However, this will only work in the "Current File" asset
library, since that is the only library that allows changing assets,
which is what's done here.

While dragging assets over the tree row, a tooltip is shown explaining
what's going to happen.

In preparation to this, the new UI tree-view API was already extended
with custom drop support, see 4ee2d9df428d.

----

Changes here to the `wmDrag` code were needed to support dragging multiple
assets. Some of it is considered temporary because a) a proper #AssetHandle
design should replace some ugly parts of this patch and b) the multi-item
support in `wmDrag` isn't that great yet. The entire API will have to be
written anyway (see D4071).

Maniphest Tasks: T91573

Differential Revision: https://developer.blender.org/D12713

Reviewed by: Sybren Stüvel

1 files changed, 1 insertions, 0 deletions

diff --git a/source/blender/editors/space_file/filelist.h b/source/blender/editors/space_file/filelist.h
index d1f37b5b365..c2c1211b81c 100644
--- a/source/blender/editors/space_file/filelist.h
+++ b/source/blender/editors/space_file/filelist.h
@@ -76,6 +76,7 @@ void filelist_set_asset_catalog_filter_options(
     struct FileList *filelist,
     eFileSel_Params_AssetCatalogVisibility catalog_visibility,
     const struct bUUID *catalog_id);
+void filelist_tag_needs_filtering(struct FileList *filelist);
 void filelist_filter(struct FileList *filelist);
 void filelist_setlibrary(struct FileList *filelist,
                          const struct AssetLibraryReference *asset_library_ref);