@@ -182,0 +183,4 @@
+  /**
+   * \returns the number of non-null parents of the node.
+   */
+  int depth() const;

@@ -487,6 +487,15 @@ LayerGroup *TreeNode::parent_group() const
   return nullptr;
 }
 
+int TreeNode::depth() const

@@ -490,0 +491,4 @@
+{
+  const LayerGroup *parent = this->parent_group();
+  if (parent == nullptr) {
+    return 0;

@@ -3560,0 +3561,4 @@
+static short acf_gpl_offset(bAnimContext *ac, bAnimListElem *ale)
+{
+  GreasePencilLayerTreeNode *node = static_cast<GreasePencilLayerTreeNode *>(ale->data);
+  const int depth = node->wrap().depth();

@@ -3630,6 +3666,73 @@ static bAnimChannelType ACF_GPL = {
     /*setting_ptr*/ acf_gpl_setting_ptr,
 };
 
+/* Grease Pencil Layer Group -------------------------------- */