Merge branch 'blender-v3.0-release'

2 files changed, 13 insertions, 7 deletions

diff --git a/source/blender/blenkernel/intern/material.c b/source/blender/blenkernel/intern/material.c
index 5f726defb1a..3a4e39812ab 100644
--- a/source/blender/blenkernel/intern/material.c
+++ b/source/blender/blenkernel/intern/material.c
@@ -899,7 +899,17 @@ void BKE_object_materials_test(Main *bmain, Object *ob, ID *id)
     return;
   }
 
-  BKE_object_material_resize(bmain, ob, *totcol, false);
+  if ((ob->id.tag & LIB_TAG_MISSING) == 0 && (id->tag & LIB_TAG_MISSING) != 0) {
+    /* Exception: In case the object is a valid data, but its obdata is an empty place-holder,
+     * use object's material slots amount as reference.
+     * This avoids loosing materials in a local object when its linked obdata gets missing.
+     * See T92780. */
+    BKE_id_material_resize(bmain, id, (short)ob->totcol, false);
+  }
+  else {
+    /* Normal case: the use the obdata amount of materials slots to update the object's one. */
+    BKE_object_material_resize(bmain, ob, *totcol, false);
+  }
 }
 
 void BKE_objects_materials_test_all(Main *bmain, ID *id)
diff --git a/source/blender/blenkernel/intern/object.c b/source/blender/blenkernel/intern/object.c
index 4eecb2b6cf7..b5d39921f26 100644
--- a/source/blender/blenkernel/intern/object.c
+++ b/source/blender/blenkernel/intern/object.c
@@ -869,6 +869,7 @@ static void object_blend_read_lib(BlendLibReader *reader, ID *id)
 {
   Object *ob = (Object *)id;
 
+  Main *bmain = BLO_read_lib_get_main(reader);
   BlendFileReadReport *reports = BLO_read_lib_reports(reader);
 
   /* XXX deprecated - old animation system <<< */
@@ -965,12 +966,7 @@ static void object_blend_read_lib(BlendLibReader *reader, ID *id)
   /* When the object is local and the data is library its possible
    * the material list size gets out of sync. T22663. */
   if (ob->data && ob->id.lib != ((ID *)ob->data)->lib) {
-    const short *totcol_data = BKE_object_material_len_p(ob);
-    /* Only expand so as not to lose any object materials that might be set. */
-    if (totcol_data && (*totcol_data > ob->totcol)) {
-      // printf("'%s' %d -> %d\n", ob->id.name, ob->totcol, *totcol_data);
-      BKE_object_material_resize(BLO_read_lib_get_main(reader), ob, *totcol_data, false);
-    }
+    BKE_object_materials_test(bmain, ob, ob->data);
   }
 
   BLO_read_id_address(reader, ob->id.lib, &ob->gpd);