release/scripts/startup/bl_ui/node_add_menu.py

@@ -35,19 +35,10 @@ def draw_node_group_add_menu(context, layout):
     if node_tree:
         from nodeitems_builtins import node_tree_group_type
 
-        def contains_group(nodetree, group):
-            if nodetree == group:
-                return True
-            for node in nodetree.nodes:
-                if node.bl_idname in node_tree_group_type.values() and node.node_tree is not None:
-                    if contains_group(node.node_tree, group):
-                        return True
-            return False
-
         groups = [
             group for group in context.blend_data.node_groups
             if (group.bl_idname == node_tree.bl_idname and
-                not contains_group(group, node_tree) and
+                not group.contains_tree(node_tree) and
                 not group.name.startswith('.'))
         ]
         if groups:

release/scripts/startup/nodeitems_builtins.py

@@ -76,21 +76,11 @@ def node_group_items(context):
 
     yield NodeItemCustom(draw=lambda self, layout, context: layout.separator())
 
-    def contains_group(nodetree, group):
-        if nodetree == group:
-            return True
-        else:
-            for node in nodetree.nodes:
-                if node.bl_idname in node_tree_group_type.values() and node.node_tree is not None:
-                    if contains_group(node.node_tree, group):
-                        return True
-        return False
-
     for group in context.blend_data.node_groups:
         if group.bl_idname != ntree.bl_idname:
             continue
         # filter out recursive groups
-        if contains_group(group, ntree):
+        if group.contains_tree(ntree):
             continue
         # filter out hidden nodetrees
         if group.name.startswith('.'):

source/blender/blenkernel/BKE_node.h

@@ -504,7 +504,13 @@ struct bNodeTree *ntreeFromID(struct ID *id);
 void ntreeFreeLocalNode(struct bNodeTree *ntree, struct bNode *node);
 void ntreeFreeLocalTree(struct bNodeTree *ntree);
 struct bNode *ntreeFindType(struct bNodeTree *ntree, int type);
-bool ntreeHasTree(const struct bNodeTree *ntree, const struct bNodeTree *lookup);
+
+/**
+ * Check recursively if a node tree contains another.
+ */
+bool ntreeContainsTree(const struct bNodeTree *tree_to_search_in,
+                       const struct bNodeTree *tree_to_search_for);
+
 void ntreeUpdateAllNew(struct Main *main);
 void ntreeUpdateAllUsers(struct Main *main, struct ID *id);
 

source/blender/blenkernel/intern/node.cc

@@ -3457,21 +3457,41 @@ bNode *ntreeFindType(bNodeTree *ntree, int type)
   return nullptr;
 }
 
-bool ntreeHasTree(const bNodeTree *ntree, const bNodeTree *lookup)
+static bool ntree_contains_tree_exec(const bNodeTree *tree_to_search_in,
+                                     const bNodeTree *tree_to_search_for,
+                                     Set<const bNodeTree *> &already_passed)
 {
-  if (ntree == lookup) {
+  if (tree_to_search_in == tree_to_search_for) {
     return true;
   }
-  for (const bNode *node : ntree->all_nodes()) {
-    if (ELEM(node->type, NODE_GROUP, NODE_CUSTOM_GROUP) && node->id) {
-      if (ntreeHasTree((bNodeTree *)node->id, lookup)) {
-        return true;
-      }
+
+  tree_to_search_in->ensure_topology_cache();
+  for (const bNode *node_group : tree_to_search_in->group_nodes()) {
+    const bNodeTree *sub_tree_search_in = reinterpret_cast<const bNodeTree *>(node_group->id);
+    if (!sub_tree_search_in) {
+      continue;
+    }
+    if (!already_passed.add(sub_tree_search_in)) {
+      continue;
+    }
+    if (ntree_contains_tree_exec(sub_tree_search_in, tree_to_search_for, already_passed)) {
+      return true;
     }
   }
+
   return false;
 }
 
+bool ntreeContainsTree(const bNodeTree *tree_to_search_in, const bNodeTree *tree_to_search_for)
+{
+  if (tree_to_search_in == tree_to_search_for) {
+    return true;
+  }
+
+  Set<const bNodeTree *> already_passed;
+  return ntree_contains_tree_exec(tree_to_search_in, tree_to_search_for, already_passed);
+}
+
 bNodeLink *nodeFindLink(bNodeTree *ntree, const bNodeSocket *from, const bNodeSocket *to)
 {
   LISTBASE_FOREACH (bNodeLink *, link, &ntree->links) {

source/blender/editors/space_node/node_edit.cc

@@ -715,7 +715,7 @@ void ED_node_set_active(
     if ((node->flag & NODE_ACTIVE_TEXTURE) && !was_active_texture) {
       /* If active texture changed, free glsl materials. */
       LISTBASE_FOREACH (Material *, ma, &bmain->materials) {
-        if (ma->nodetree && ma->use_nodes && ntreeHasTree(ma->nodetree, ntree)) {
+        if (ma->nodetree && ma->use_nodes && ntreeContainsTree(ma->nodetree, ntree)) {
           GPU_material_free(&ma->gpumaterial);
 
           /* Sync to active texpaint slot, otherwise we can end up painting on a different slot
@@ -734,7 +734,7 @@ void ED_node_set_active(
       }
 
       LISTBASE_FOREACH (World *, wo, &bmain->worlds) {
-        if (wo->nodetree && wo->use_nodes && ntreeHasTree(wo->nodetree, ntree)) {
+        if (wo->nodetree && wo->use_nodes && ntreeContainsTree(wo->nodetree, ntree)) {
           GPU_material_free(&wo->gpumaterial);
         }
       }

source/blender/editors/space_node/node_group.cc

@@ -1094,24 +1094,6 @@ void NODE_OT_group_make(wmOperatorType *ot)
 /** \name Group Insert Operator
  * \{ */
 
-static bool node_tree_contains_tree_recursive(const bNodeTree &ntree_to_search_in,
-                                              const bNodeTree &ntree_to_search_for)
-{
-  if (&ntree_to_search_in == &ntree_to_search_for) {
-    return true;
-  }
-  ntree_to_search_in.ensure_topology_cache();
-  for (const bNode *node : ntree_to_search_in.group_nodes()) {
-    if (node->id) {
-      if (node_tree_contains_tree_recursive(*reinterpret_cast<bNodeTree *>(node->id),
-                                            ntree_to_search_for)) {
-        return true;
-      }
-    }
-  }
-  return false;
-}
-
 static int node_group_insert_exec(bContext *C, wmOperator *op)
 {
   SpaceNode *snode = CTX_wm_space_node(C);
@@ -1133,7 +1115,7 @@ static int node_group_insert_exec(bContext *C, wmOperator *op)
     if (!group->is_group() || group->id == nullptr) {
       continue;
     }
-    if (node_tree_contains_tree_recursive(*reinterpret_cast<bNodeTree *>(group->id), *ngroup)) {
+    if (ntreeContainsTree(reinterpret_cast<bNodeTree *>(group->id), ngroup)) {
       BKE_reportf(
           op->reports, RPT_WARNING, "Can not insert group '%s' in '%s'", group->name, gnode->name);
       return OPERATOR_CANCELLED;

source/blender/makesrna/intern/rna_nodetree.c

@@ -1435,6 +1435,11 @@ static void rna_NodeTree_active_output_set(PointerRNA *ptr, int value)
   }
 }
 
+static bool rna_NodeTree_contains_tree(bNodeTree *tree, bNodeTree *sub_tree)
+{
+  return ntreeContainsTree(tree, sub_tree);
+}
+
 static bNodeSocket *rna_NodeTree_inputs_new(
     bNodeTree *ntree, Main *bmain, ReportList *reports, const char *type, const char *name)
 {
@@ -12719,6 +12724,16 @@ static void rna_def_nodetree(BlenderRNA *brna)
   parm = RNA_def_pointer(func, "context", "Context", "", "");
   RNA_def_parameter_flags(parm, PROP_NEVER_NULL, PARM_REQUIRED);
 
+  func = RNA_def_function(srna, "contains_tree", "rna_NodeTree_contains_tree");
+  RNA_def_function_ui_description(
+      func,
+      "Check if the node tree contains another. Used to avoid creating recursive node groups");
+  parm = RNA_def_pointer(
+      func, "sub_tree", "NodeTree", "Node Tree", "Node tree for recursive check");
+  RNA_def_parameter_flags(parm, PROP_NEVER_NULL, PARM_REQUIRED);
+  parm = RNA_def_property(func, "contained", PROP_BOOLEAN, PROP_NONE);
+  RNA_def_function_return(func, parm);
+
   /* registration */
   prop = RNA_def_property(srna, "bl_idname", PROP_STRING, PROP_NONE);
   RNA_def_property_string_sdna(prop, NULL, "typeinfo->idname");