1 files changed, 31 insertions, 1 deletions

diff --git a/source/blender/nodes/function/nodes/node_fn_group_instance_id.cc b/source/blender/nodes/function/nodes/node_fn_group_instance_id.cc
index 2ac86ee2407..c61c941ee0d 100644
--- a/source/blender/nodes/function/nodes/node_fn_group_instance_id.cc
+++ b/source/blender/nodes/function/nodes/node_fn_group_instance_id.cc
@@ -1,15 +1,45 @@
-#include "node_function_util.h"
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "node_function_util.hh"
 
 static bNodeSocketTemplate fn_node_group_instance_id_out[] = {
     {SOCK_STRING, N_("Identifier")},
     {-1, ""},
 };
 
+static void fn_node_group_instance_id_expand_in_mf_network(
+    blender::bke::NodeMFNetworkBuilder &builder)
+{
+  const blender::bke::DNode &node = builder.dnode();
+  std::string id = "/";
+  for (const blender::bke::DParentNode *parent = node.parent(); parent;
+       parent = parent->parent()) {
+    id = "/" + parent->node_ref().name() + id;
+  }
+  builder.construct_and_set_matching_fn<blender::fn::CustomMF_Constant<std::string>>(
+      std::move(id));
+}
+
 void register_node_type_fn_group_instance_id()
 {
   static bNodeType ntype;
 
   fn_node_type_base(&ntype, FN_NODE_GROUP_INSTANCE_ID, "Group Instance ID", 0, 0);
   node_type_socket_templates(&ntype, nullptr, fn_node_group_instance_id_out);
+  ntype.expand_in_mf_network = fn_node_group_instance_id_expand_in_mf_network;
   nodeRegisterType(&ntype);
 }