1 files changed, 9 insertions, 0 deletions
diff --git a/source/blender/makesdna/DNA_ID.h b/source/blender/makesdna/DNA_ID.h
index 7ce84e0092c..0cf45fa4bcc 100644
--- a/source/blender/makesdna/DNA_ID.h
+++ b/source/blender/makesdna/DNA_ID.h
@@ -680,6 +680,15 @@ typedef enum IDRecalcFlag {
    * input file or for color space changes. */
   ID_RECALC_SOURCE = (1 << 23),
 
+  /* Virtual recalc tag/marker required for undo in some cases, where actual data does not change
+   * and hence do not require an update, but conceptually we are dealing with something new.
+   *
+   * Current known case: linked IDs made local without requiring any copy. While their users do not
+   * require any update, they have actually been 'virtually' remapped from the linked ID to the
+   * local one.
+   */
+  ID_RECALC_TAG_FOR_UNDO = (1 << 24),
+
   /***************************************************************************
    * Pseudonyms, to have more semantic meaning in the actual code without
    * using too much low-level and implementation specific tags. */