Fix T91197: marking assets from Python may crash

When using `asset_mark` function from a Python script and afterwards
updating the preview image, a crash might happen. The preview image is
generated by the `asset_mark` function. This may happen on a background
thread, introducing potential synchronization issues.

This patch fixes this by separating the preview generation
`ID.asset_generate_preview` from the mark as asset `ID.asset_mark`.

Note: this separation of "mark as asset" and "generate preview" also
applies to the `ED_asset_mark_id()` C function; if it is desired to have
previews rendered after marking as asset, a call to
`ED_asset_generate_preview()` is now also required.

Reviewed By: sybren

Maniphest Tasks: T91197

Differential Revision: https://developer.blender.org/D12922

1 files changed, 3 insertions, 1 deletions

diff --git a/source/blender/editors/asset/intern/asset_ops.cc b/source/blender/editors/asset/intern/asset_ops.cc
index bf532903c7c..33a22775280 100644
--- a/source/blender/editors/asset/intern/asset_ops.cc
+++ b/source/blender/editors/asset/intern/asset_ops.cc
@@ -145,7 +145,9 @@ void AssetMarkHelper::operator()(const bContext &C, PointerRNAVec &ids)
       continue;
     }
 
-    if (ED_asset_mark_id(&C, id)) {
+    if (ED_asset_mark_id(id)) {
+      ED_asset_generate_preview(&C, id);
+
       stats.last_id = id;
       stats.tot_created++;
     }