6 files changed, 41 insertions, 7 deletions

diff --git a/intern/cycles/app/cycles_xml.cpp b/intern/cycles/app/cycles_xml.cpp
index 1dbe8a30ff2..bdb014d31ef 100644
--- a/intern/cycles/app/cycles_xml.cpp
+++ b/intern/cycles/app/cycles_xml.cpp
@@ -326,6 +326,10 @@ static void xml_read_shader_graph(XMLReadState &state, Shader *shader, xml_node
         fprintf(stderr, "Node type \"%s\" is not a shader node.\n", node_type->name.c_str());
         continue;
       }
+      else if (node_type->create == NULL) {
+        fprintf(stderr, "Can't create abstract node type \"%s\".\n", node_type->name.c_str());
+        continue;
+      }
 
       snode = (ShaderNode *)node_type->create(node_type);
     }
diff --git a/intern/cycles/graph/node.cpp b/intern/cycles/graph/node.cpp
index 4f79a7518dc..1439fb5a407 100644
--- a/intern/cycles/graph/node.cpp
+++ b/intern/cycles/graph/node.cpp
@@ -669,4 +669,14 @@ size_t Node::get_total_size_in_bytes() const
   return total_size;
 }
 
+bool Node::is_a(const NodeType *type_)
+{
+  for (const NodeType *base = type; base; base = base->base) {
+    if (base == type_) {
+      return true;
+    }
+  }
+  return false;
+}
+
 CCL_NAMESPACE_END
diff --git a/intern/cycles/graph/node.h b/intern/cycles/graph/node.h
index d35a1bb489c..4473b8aca28 100644
--- a/intern/cycles/graph/node.h
+++ b/intern/cycles/graph/node.h
@@ -94,6 +94,9 @@ struct Node {
   /* Get total size of this node. */
   size_t get_total_size_in_bytes() const;
 
+  /* Type testing, taking into account base classes. */
+  bool is_a(const NodeType *type);
+
   ustring name;
   const NodeType *type;
 };
diff --git a/intern/cycles/graph/node_type.cpp b/intern/cycles/graph/node_type.cpp
index f46d4e48026..0283ed7c817 100644
--- a/intern/cycles/graph/node_type.cpp
+++ b/intern/cycles/graph/node_type.cpp
@@ -135,8 +135,13 @@ bool SocketType::is_float3(Type type)
 
 /* Node Type */
 
-NodeType::NodeType(Type type_) : type(type_)
+NodeType::NodeType(Type type, const NodeType *base) : type(type), base(base)
 {
+  if (base) {
+    /* Inherit sockets. */
+    inputs = base->inputs;
+    outputs = base->outputs;
+  }
 }
 
 NodeType::~NodeType()
@@ -209,7 +214,7 @@ unordered_map<ustring, NodeType, ustringHash> &NodeType::types()
   return _types;
 }
 
-NodeType *NodeType::add(const char *name_, CreateFunc create_, Type type_)
+NodeType *NodeType::add(const char *name_, CreateFunc create_, Type type_, const NodeType *base_)
 {
   ustring name(name_);
 
@@ -219,7 +224,7 @@ NodeType *NodeType::add(const char *name_, CreateFunc create_, Type type_)
     return NULL;
   }
 
-  types()[name] = NodeType(type_);
+  types()[name] = NodeType(type_, base_);
 
   NodeType *type = &types()[name];
   type->name = name;
diff --git a/intern/cycles/graph/node_type.h b/intern/cycles/graph/node_type.h
index e9496a42658..a4461ec7abb 100644
--- a/intern/cycles/graph/node_type.h
+++ b/intern/cycles/graph/node_type.h
@@ -103,7 +103,7 @@ struct SocketType {
 struct NodeType {
   enum Type { NONE, SHADER };
 
-  explicit NodeType(Type type = NONE);
+  explicit NodeType(Type type = NONE, const NodeType *base = NULL);
   ~NodeType();
 
   void register_input(ustring name,
@@ -124,11 +124,15 @@ struct NodeType {
 
   ustring name;
   Type type;
+  const NodeType *base;
   vector<SocketType, std::allocator<SocketType>> inputs;
   vector<SocketType, std::allocator<SocketType>> outputs;
   CreateFunc create;
 
-  static NodeType *add(const char *name, CreateFunc create, Type type = NONE);
+  static NodeType *add(const char *name,
+                       CreateFunc create,
+                       Type type = NONE,
+                       const NodeType *base = NULL);
   static const NodeType *find(ustring name);
   static unordered_map<ustring, NodeType, ustringHash> &types();
 };
@@ -148,6 +152,14 @@ struct NodeType {
   } \
   template<typename T> const NodeType *structname::register_type()
 
+#define NODE_ABSTRACT_DECLARE \
+  template<typename T> static const NodeType *register_type(); \
+  static const NodeType *node_type;
+
+#define NODE_ABSTRACT_DEFINE(structname) \
+  const NodeType *structname::node_type = structname::register_type<structname>(); \
+  template<typename T> const NodeType *structname::register_type()
+
 /* Sock Definition Macros */
 
 #define SOCKET_OFFSETOF(T, name) (((char *)&(((T *)1)->name)) - (char *)1)
diff --git a/intern/cycles/graph/node_xml.cpp b/intern/cycles/graph/node_xml.cpp
index a96970cc904..d333400cc4a 100644
--- a/intern/cycles/graph/node_xml.cpp
+++ b/intern/cycles/graph/node_xml.cpp
@@ -200,7 +200,7 @@ void xml_read_node(XMLReader &reader, Node *node, xml_node xml_node)
         map<ustring, Node *>::iterator it = reader.node_map.find(value);
         if (it != reader.node_map.end()) {
           Node *value_node = it->second;
-          if (value_node->type == *(socket.node_type))
+          if (value_node->is_a(*(socket.node_type)))
             node->set(socket, it->second);
         }
         break;
@@ -215,7 +215,7 @@ void xml_read_node(XMLReader &reader, Node *node, xml_node xml_node)
           map<ustring, Node *>::iterator it = reader.node_map.find(ustring(tokens[i]));
           if (it != reader.node_map.end()) {
             Node *value_node = it->second;
-            value[i] = (value_node->type == *(socket.node_type)) ? value_node : NULL;
+            value[i] = (value_node->is_a(*(socket.node_type))) ? value_node : NULL;
           }
           else {
             value[i] = NULL;