VSE: Disable interactivity in combined view

Combined view of timeline and preview causes seemingly unpredictable
behavior after some operators have been allowed to run in preview
region.

Disable new features in this combined view, so behavior should be
consistent with previous versions.

ref: https://developer.blender.org/T92584

Reviewed By: campbellbarton

Differential Revision: https://developer.blender.org/D13419

1 files changed, 26 insertions, 3 deletions

diff --git a/source/blender/editors/space_sequencer/sequencer_edit.c b/source/blender/editors/space_sequencer/sequencer_edit.c
index 899c2f6b4f4..ce538961875 100644
--- a/source/blender/editors/space_sequencer/sequencer_edit.c
+++ b/source/blender/editors/space_sequencer/sequencer_edit.c
@@ -210,7 +210,7 @@ bool sequencer_strip_has_path_poll(bContext *C)
           (SEQ_HAS_PATH(seq)));
 }
 
-bool sequencer_view_preview_poll(bContext *C)
+bool sequencer_view_has_preview_poll(bContext *C)
 {
   SpaceSeq *sseq = CTX_wm_space_seq(C);
   if (sseq == NULL) {
@@ -231,6 +231,26 @@ bool sequencer_view_preview_poll(bContext *C)
   return true;
 }
 
+bool sequencer_view_preview_only_poll(const bContext *C)
+{
+  SpaceSeq *sseq = CTX_wm_space_seq(C);
+  if (sseq == NULL) {
+    return false;
+  }
+  if (SEQ_editing_get(CTX_data_scene(C)) == NULL) {
+    return false;
+  }
+  if (!(ELEM(sseq->view, SEQ_VIEW_PREVIEW) && (sseq->mainb == SEQ_DRAW_IMG_IMBUF))) {
+    return false;
+  }
+  ARegion *region = CTX_wm_region(C);
+  if (!(region && region->regiontype == RGN_TYPE_PREVIEW)) {
+    return false;
+  }
+
+  return true;
+}
+
 bool sequencer_view_strips_poll(bContext *C)
 {
   SpaceSeq *sseq = CTX_wm_space_seq(C);
@@ -1710,8 +1730,11 @@ static int sequencer_delete_exec(bContext *C, wmOperator *UNUSED(op))
 
   SEQ_prefetch_stop(scene);
 
-  const bool is_preview = sequencer_view_preview_poll(C);
+  const bool is_preview = sequencer_view_has_preview_poll(C);
   if (is_preview) {
+    if (!sequencer_view_preview_only_poll(C)) {
+      return OPERATOR_CANCELLED;
+    }
     SEQ_query_rendered_strips_to_tag(seqbasep, scene->r.cfra, 0);
   }
 
@@ -3438,7 +3461,7 @@ void SEQUENCER_OT_cursor_set(wmOperatorType *ot)
   /* api callbacks */
   ot->exec = sequencer_set_2d_cursor_exec;
   ot->invoke = sequencer_set_2d_cursor_invoke;
-  ot->poll = sequencer_view_preview_poll;
+  ot->poll = sequencer_view_has_preview_poll;
 
   /* flags */
   ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;