@@ -0,0 +38,4 @@
+ * \{ */
+
+struct StepDrawingGeometry {
+  bke::CurvesGeometry geometry = {};

@@ -0,0 +39,4 @@
+
+struct StepDrawingGeometry {
+  bke::CurvesGeometry geometry = {};
+  uint32_t index;

@@ -0,0 +95,4 @@
+      }
+    }
+
+    new (&drawings_geometry) Array<StepDrawingGeometry>(drawings_geometry_num);

@@ -0,0 +100,4 @@
+
+    uint32_t drawings_geometry_idx = 0;
+    uint32_t drawings_reference_idx = 0;
+    for (int idx = 0; idx < grease_pencil.drawing_array_num; idx++) {

@@ -0,0 +68,4 @@
+  void decode(GreasePencil & /* grease_pencil */) const {}
+};
+
+struct StepObject {

@@ -841,0 +882,4 @@
+    runtime = MEM_new<blender::bke::greasepencil::LayerRuntime>(__func__);
+  }
+  for (int i = 0; i < frames_storage.num; i++) {
+    frames_for_write().add_new(frames_storage.keys[i], frames_storage.values[i]);

@@ -899,1 +947,4 @@
 
+LayerGroup &LayerGroup::operator=(const LayerGroup &other)
+{
+  this->~LayerGroup();

@@ -1109,0 +1175,4 @@
+        child->as_group().prepare_for_dna_write();
+        break;
+      }
+      default:

@@ -0,0 +71,4 @@
+
+struct StepDrawingGeometryBase {
+  /* Index of this drawing in the original combined array of all drawings in GreasePencil ID. */
+  uint index;

@@ -0,0 +81,4 @@
+  bke::CurvesGeometry geometry;
+
+  void encode(const GreasePencilDrawing &drawing_geometry,
+              const int64_t drawing_index,

@@ -0,0 +96,4 @@
+    MutableSpan<GreasePencilDrawingBase *> drawings = grease_pencil.drawings();
+    if (drawings[index] == nullptr) {
+      drawings[index] = reinterpret_cast<GreasePencilDrawingBase *>(
+          MEM_new<blender::bke::greasepencil::Drawing>(__func__));

@@ -0,0 +176,4 @@
+    drawings_reference.reinitialize(drawings_reference_num);
+
+    uint drawings_geometry_idx = 0;
+    uint drawings_reference_idx = 0;

@@ -841,0 +875,4 @@
+  /* Re-create frames data in runtime map. */
+  /* NOTE: Avoid re-allocating runtime data to reduce 'false positive' change detections from
+   * memfile undo. */
+  if (runtime) {

@@ -1108,1 +1169,4 @@
 
+void LayerGroup::prepare_for_dna_write()
+{
+  LISTBASE_FOREACH (TreeNode *, child, &children) {

@@ -1109,0 +1185,4 @@
+
+void LayerGroup::update_from_dna_read()
+{
+  LISTBASE_FOREACH (TreeNode *, child, &children) {

@@ -0,0 +49,4 @@
+ *
+ * Each drawing type has its own array in the undo #StepObject data.
+ *
+ * NOTE: Current code assumes that drawing can only be added or removed, but never re-ordered.

@@ -0,0 +94,4 @@
+  void decode(GreasePencil &grease_pencil, StepDecodeStatus & /*decode_status*/) const
+  {
+    MutableSpan<GreasePencilDrawingBase *> drawings = grease_pencil.drawings();
+    if (drawings[index] == nullptr) {

@@ -0,0 +210,4 @@
+
+  void encode_layers(const GreasePencil &grease_pencil, StepEncodeStatus & /*encode_status*/)
+  {
+    layers_num = int(grease_pencil.layers().size());

@@ -0,0 +278,4 @@
+  Scene *scene = CTX_data_scene(C);
+  ViewLayer *view_layer = CTX_data_view_layer(C);
+  uint objects_num = 0;
+  Object **objects = ED_undo_editmode_objects_from_view_layer(scene, view_layer, &objects_num);

@@ -0,0 +281,4 @@
+  Object **objects = ED_undo_editmode_objects_from_view_layer(scene, view_layer, &objects_num);
+
+  us->scene_ref.ptr = scene;
+  new (&us->objects) Array<StepObject>(objects_num);

@@ -0,0 +114,4 @@
+};
+
+class StepDrawingGeometry : public StepDrawingGeometryBase {
+ private:

@@ -1566,1 +1578,4 @@
 
+void GreasePencil::resize_drawings(const int new_num)
+{
+  using namespace blender;

@@ -1567,0 +1589,4 @@
+  }
+  else { /* if (new_num < prev_num) */
+    const int shrink_num = prev_num - new_num;
+    MutableSpan<GreasePencilDrawingBase *> old_drawings = this->drawings().drop_front(prev_num);

@@ -0,0 +141,4 @@
+    drawing_geometry.base.flag = flag_;
+    drawing_geometry.geometry.wrap() = geometry_;
+
+    /* TODO: Check if there is a way to tell if both stored and current geometry are still the

@@ -515,0 +515,4 @@
+
+  /**
+   * Low-level resizing of drawings array. Only allocates new entries in the array, no drawings are
+   * created in case of size increase.