VSE: Add API function to select displayed meta strip

Use function `sequence_editor.display_stack(meta_strip)` to set
displayed timeline content.

To view top-level timeline, that does not belong to any meta strip, pass
`None` as argument.

Differential Revision: https://developer.blender.org/D12048

1 files changed, 6 insertions, 10 deletions

diff --git a/source/blender/editors/space_sequencer/sequencer_edit.c b/source/blender/editors/space_sequencer/sequencer_edit.c
index 16f663110ec..76dd43586d1 100644
--- a/source/blender/editors/space_sequencer/sequencer_edit.c
+++ b/source/blender/editors/space_sequencer/sequencer_edit.c
@@ -1911,11 +1911,9 @@ static int sequencer_meta_toggle_exec(bContext *C, wmOperator *UNUSED(op))
   SEQ_prefetch_stop(scene);
 
   if (active_seq && active_seq->type == SEQ_TYPE_META && active_seq->flag & SELECT) {
-    /* Enter meta-strip. */
-    SEQ_meta_stack_alloc(ed, active_seq);
-    SEQ_seqbase_active_set(ed, &active_seq->seqbase);
-    SEQ_channels_displayed_set(ed, &active_seq->channels);
+    /* Deselect active meta seq. */
     SEQ_select_active_set(scene, NULL);
+    SEQ_meta_stack_set(scene, active_seq);
   }
   else {
     /* Exit meta-strip if possible. */
@@ -1923,14 +1921,12 @@ static int sequencer_meta_toggle_exec(bContext *C, wmOperator *UNUSED(op))
       return OPERATOR_CANCELLED;
     }
 
-    MetaStack *ms = SEQ_meta_stack_active_get(ed);
-    SEQ_seqbase_active_set(ed, ms->oldbasep);
-    SEQ_channels_displayed_set(ed, ms->old_channels);
-    SEQ_select_active_set(scene, ms->parseq);
-    SEQ_meta_stack_free(ed, ms);
+    /* Display parent meta. */
+    Sequence *meta_parent = SEQ_meta_stack_pop(ed);
+    SEQ_select_active_set(scene, meta_parent);
   }
 
-  DEG_id_tag_update(&scene->id, ID_RECALC_SEQUENCER_STRIPS);
+  // DEG_id_tag_update(&scene->id, ID_RECALC_SEQUENCER_STRIPS);
   WM_event_add_notifier(C, NC_SCENE | ND_SEQUENCER, scene);
 
   return OPERATOR_FINISHED;