1 files changed, 47 insertions, 5 deletions

diff --git a/source/blender/editors/animation/anim_channels_edit.c b/source/blender/editors/animation/anim_channels_edit.c
index ba3796ad245..124992bed71 100644
--- a/source/blender/editors/animation/anim_channels_edit.c
+++ b/source/blender/editors/animation/anim_channels_edit.c
@@ -49,6 +49,7 @@
 #include "BKE_gpencil.h"
 #include "BKE_lib_id.h"
 #include "BKE_mask.h"
+#include "BKE_nla.h"
 #include "BKE_scene.h"
 
 #include "DEG_depsgraph.h"
@@ -1063,18 +1064,27 @@ static void rearrange_animchannels_filter_visible(ListBase *anim_data_visible,
                                                   eAnim_ChannelType type)
 {
   ListBase anim_data = {NULL, NULL};
-  bAnimListElem *ale, *ale_next;
-  int filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_LIST_VISIBLE | ANIMFILTER_LIST_CHANNELS);
+  eAnimFilter_Flags filter = (ANIMFILTER_DATA_VISIBLE | ANIMFILTER_LIST_VISIBLE |
+                              ANIMFILTER_LIST_CHANNELS);
 
   /* get all visible channels */
   ANIM_animdata_filter(ac, &anim_data, filter, ac->data, ac->datatype);
 
   /* now, only keep the ones that are of the types we are interested in */
-  for (ale = anim_data.first; ale; ale = ale_next) {
-    ale_next = ale->next;
-
+  LISTBASE_FOREACH_MUTABLE (bAnimListElem *, ale, &anim_data) {
     if (ale->type != type) {
       BLI_freelinkN(&anim_data, ale);
+      continue;
+    }
+
+    if (type == ANIMTYPE_NLATRACK) {
+      NlaTrack *nlt = (NlaTrack *)ale->data;
+
+      if (BKE_nlatrack_is_nonlocal_in_liboverride(ale->id, nlt)) {
+        /* No re-arrangement of non-local tracks of override data. */
+        BLI_freelinkN(&anim_data, ale);
+        continue;
+      }
     }
   }
 
@@ -1146,6 +1156,7 @@ static void rearrange_nla_channels(bAnimContext *ac, AnimData *adt, eRearrangeAn
 {
   AnimChanRearrangeFp rearrange_func;
   ListBase anim_data_visible = {NULL, NULL};
+  const bool is_liboverride = ID_IS_OVERRIDE_LIBRARY(ac->obact);
 
   /* hack: invert mode so that functions will work in right order */
   mode *= -1;
@@ -1156,6 +1167,29 @@ static void rearrange_nla_channels(bAnimContext *ac, AnimData *adt, eRearrangeAn
     return;
   }
 
+  /* In liboverride case, we need to extract non-local NLA tracks from current anim data before we
+   * can perform the move, and add then back afterwards. It's the only way to prevent them from
+   * being affected by the reordering.
+   *
+   * Note that both override apply code for NLA tracks collection, and NLA editing code, are
+   * responsible to ensure that non-local tracks always remain first in the list. */
+  ListBase extracted_nonlocal_nla_tracks = {NULL, NULL};
+  if (is_liboverride) {
+    NlaTrack *nla_track;
+    for (nla_track = adt->nla_tracks.first; nla_track != NULL; nla_track = nla_track->next) {
+      if (!BKE_nlatrack_is_nonlocal_in_liboverride(&ac->obact->id, nla_track)) {
+        break;
+      }
+    }
+    if (nla_track != NULL && nla_track->prev != NULL) {
+      extracted_nonlocal_nla_tracks.first = adt->nla_tracks.first;
+      extracted_nonlocal_nla_tracks.last = nla_track->prev;
+      adt->nla_tracks.first = nla_track;
+      nla_track->prev->next = NULL;
+      nla_track->prev = NULL;
+    }
+  }
+
   /* Filter visible data. */
   rearrange_animchannels_filter_visible(&anim_data_visible, ac, ANIMTYPE_NLATRACK);
 
@@ -1163,6 +1197,14 @@ static void rearrange_nla_channels(bAnimContext *ac, AnimData *adt, eRearrangeAn
   rearrange_animchannel_islands(
       &adt->nla_tracks, rearrange_func, mode, ANIMTYPE_NLATRACK, &anim_data_visible);
 
+  /* Add back non-local NLA tracks at the begining of the animation data's list. */
+  if (!BLI_listbase_is_empty(&extracted_nonlocal_nla_tracks)) {
+    BLI_assert(is_liboverride);
+    ((NlaTrack *)extracted_nonlocal_nla_tracks.last)->next = adt->nla_tracks.first;
+    ((NlaTrack *)adt->nla_tracks.first)->prev = extracted_nonlocal_nla_tracks.last;
+    adt->nla_tracks.first = extracted_nonlocal_nla_tracks.first;
+  }
+
   /* free temp data */
   BLI_freelistN(&anim_data_visible);
 }