VSE: Image transform tools

Add tools for image manipulation in sequencer preview region.

This includes:
- Translate, rotate and resize operators, tools and gizmos
- Origin for image transformation
- Median point and individual origins pivot modes
- Select and Box select operator works in preview
- Image overlay drawing

ref T90156

Reviewed By: campbellbarton

Differential Revision: https://developer.blender.org/D12105

source/blender/blenloader/intern/versioning_300.c

@@ -64,6 +64,7 @@
 #include "MEM_guardedalloc.h"
 #include "readfile.h"
 
+#include "SEQ_iterator.h"
 #include "SEQ_sequencer.h"
 
 #include "RNA_access.h"
@@ -774,6 +775,14 @@ static void version_geometry_nodes_change_legacy_names(bNodeTree *ntree)
     }
   }
 }
+static bool seq_transform_origin_set(Sequence *seq, void *UNUSED(user_data))
+{
+  StripTransform *transform = seq->strip->transform;
+  if (seq->strip->transform != NULL) {
+    transform->origin[0] = transform->origin[1] = 0.5f;
+  }
+  return true;
+}
 
 /* NOLINTNEXTLINE: readability-function-size */
 void blo_do_versions_300(FileData *fd, Library *UNUSED(lib), Main *bmain)
@@ -1290,6 +1299,27 @@ void blo_do_versions_300(FileData *fd, Library *UNUSED(lib), Main *bmain)
     }
   }
 
+  if (!MAIN_VERSION_ATLEAST(bmain, 300, 24)) {
+    LISTBASE_FOREACH (Scene *, scene, &bmain->scenes) {
+      SequencerToolSettings *sequencer_tool_settings = SEQ_tool_settings_ensure(scene);
+      sequencer_tool_settings->pivot_point = V3D_AROUND_CENTER_MEDIAN;
+
+      if (scene->ed != NULL) {
+        SEQ_for_each_callback(&scene->ed->seqbase, seq_transform_origin_set, NULL);
+      }
+    }
+    LISTBASE_FOREACH (bScreen *, screen, &bmain->screens) {
+      LISTBASE_FOREACH (ScrArea *, area, &screen->areabase) {
+        LISTBASE_FOREACH (SpaceLink *, sl, &area->spacedata) {
+          if (sl->spacetype == SPACE_SEQ) {
+            SpaceSeq *sseq = (SpaceSeq *)sl;
+            sseq->preview_overlay.flag |= SEQ_PREVIEW_SHOW_OUTLINE_SELECTED;
+          }
+        }
+      }
+    }
+  }
+
   /**
    * Versioning code until next subversion bump goes here.
    *