Nodes: Duplicate Linked operator + User Preference option for Node Tree

This operator (Alt + D) allows users to explicitly create a linked copy
of a group node (same current behaviour for the Duplicate operator).

The duplicate operator (Shift + D) now takes the new User Preference
duplicate data option for Node Tree into account. It is by default
disabled, leading to no functional change for users.

Although we could make in the future make this option "on" by default,
to make it consistent with the rest of Blender we do not at the time.

Differential Revision: https://developer.blender.org/D16210

2 files changed, 35 insertions, 1 deletions

diff --git a/source/blender/editors/space_node/node_edit.cc b/source/blender/editors/space_node/node_edit.cc
index 3a80733f06c..b01be5ff234 100644
--- a/source/blender/editors/space_node/node_edit.cc
+++ b/source/blender/editors/space_node/node_edit.cc
@@ -1361,12 +1361,15 @@ static int node_duplicate_exec(bContext *C, wmOperator *op)
   SpaceNode *snode = CTX_wm_space_node(C);
   bNodeTree *ntree = snode->edittree;
   const bool keep_inputs = RNA_boolean_get(op->ptr, "keep_inputs");
+  bool linked = RNA_boolean_get(op->ptr, "linked") || ((U.dupflag & USER_DUP_NTREE) == 0);
+  const bool dupli_node_tree = !linked;
   bool changed = false;
 
   ED_preview_kill_jobs(CTX_wm_manager(C), bmain);
 
   Map<const bNode *, bNode *> node_map;
   Map<const bNodeSocket *, bNodeSocket *> socket_map;
+  Map<const ID *, ID *> duplicated_node_groups;
 
   bNode *lastnode = (bNode *)ntree->nodes.last;
   LISTBASE_FOREACH (bNode *, node, &ntree->nodes) {
@@ -1374,6 +1377,18 @@ static int node_duplicate_exec(bContext *C, wmOperator *op)
       bNode *new_node = bke::node_copy_with_mapping(
           ntree, *node, LIB_ID_COPY_DEFAULT, true, socket_map);
       node_map.add_new(node, new_node);
+
+      if (node->id && dupli_node_tree) {
+        ID *new_group = duplicated_node_groups.lookup_or_add_cb(node->id, [&]() {
+          ID *new_group = BKE_id_copy(bmain, node->id);
+          /* Remove user added by copying. */
+          id_us_min(new_group);
+          return new_group;
+        });
+        id_us_plus(new_group);
+        id_us_min(new_node->id);
+        new_node->id = new_group;
+      }
       changed = true;
     }
 
@@ -1462,6 +1477,8 @@ static int node_duplicate_exec(bContext *C, wmOperator *op)
 
 void NODE_OT_duplicate(wmOperatorType *ot)
 {
+  PropertyRNA *prop;
+
   /* identifiers */
   ot->name = "Duplicate Nodes";
   ot->description = "Duplicate selected nodes";
@@ -1476,6 +1493,13 @@ void NODE_OT_duplicate(wmOperatorType *ot)
 
   RNA_def_boolean(
       ot->srna, "keep_inputs", false, "Keep Inputs", "Keep the input links to duplicated nodes");
+
+  prop = RNA_def_boolean(ot->srna,
+                         "linked",
+                         true,
+                         "Linked",
+                         "Duplicate node but not node trees, linking to the original data");
+  RNA_def_property_flag(prop, PROP_SKIP_SAVE);
 }
 
 /* XXX: some code needing updating to operators. */
diff --git a/source/blender/editors/space_node/node_ops.cc b/source/blender/editors/space_node/node_ops.cc
index 6c52dae5b86..d45c33a3c59 100644
--- a/source/blender/editors/space_node/node_ops.cc
+++ b/source/blender/editors/space_node/node_ops.cc
@@ -174,7 +174,17 @@ void ED_operatormacros_node()
                                     "Duplicate",
                                     "Duplicate selected nodes and move them",
                                     OPTYPE_UNDO | OPTYPE_REGISTER);
-  WM_operatortype_macro_define(ot, "NODE_OT_duplicate");
+  mot = WM_operatortype_macro_define(ot, "NODE_OT_duplicate");
+  RNA_boolean_set(mot->ptr, "linked", false);
+  WM_operatortype_macro_define(ot, "NODE_OT_translate_attach");
+
+  ot = WM_operatortype_append_macro(
+      "NODE_OT_duplicate_move_linked",
+      "Duplicate Linked",
+      "Duplicate selected nodes, but not their node trees, and move them",
+      OPTYPE_UNDO | OPTYPE_REGISTER);
+  mot = WM_operatortype_macro_define(ot, "NODE_OT_duplicate");
+  RNA_boolean_set(mot->ptr, "linked", true);
   WM_operatortype_macro_define(ot, "NODE_OT_translate_attach");
 
   /* modified operator call for duplicating with input links */