New Object and Image socket types

The main difficulty with adding these types is that they are the first sockets types
that reference ID data in their `default_value`. That means that I had to add some
new logic in a few places to deal with reference counting. I hope I found all the places...
It seems to work fine in my tests.

For now these socket types can only be created using a script like the one below:
```
import bpy

class MyCustomNode(bpy.types.Node):
    bl_idname = 'CustomNodeType'
    bl_label = "Custom Node"

    def init(self, context):
        self.inputs.new('NodeSocketObject', "Object")
        self.inputs.new('NodeSocketImage', "Image")

bpy.utils.register_class(MyCustomNode)

if len(bpy.data.simulations) == 0:
    bpy.data.simulations.new("Simulation")

sim = bpy.data.simulations[0]
sim.node_tree.nodes.new("CustomNodeType")
```

After running the script, go to the simulation editor and select the newly created simulation.

---

We might want to change `readfile.c` so that linked objects/images are only loaded,
when the socket is not connected. Otherwise it can be tricky to figure out why certain
id data blocks are still referenced by the node tree later on.

Differential Revision: https://developer.blender.org/D7347

8 files changed, 327 insertions, 34 deletions

diff --git a/source/blender/blenkernel/intern/lib_query.c b/source/blender/blenkernel/intern/lib_query.c
index 90525fdde3c..8330512d265 100644
--- a/source/blender/blenkernel/intern/lib_query.c
+++ b/source/blender/blenkernel/intern/lib_query.c
@@ -205,6 +205,36 @@ static void library_foreach_idproperty_ID_link(LibraryForeachIDData *data,
   FOREACH_FINALIZE_VOID;
 }
 
+static void library_foreach_node_socket(LibraryForeachIDData *data, bNodeSocket *sock)
+{
+  library_foreach_idproperty_ID_link(data, sock->prop, IDWALK_CB_USER);
+
+  switch ((eNodeSocketDatatype)sock->type) {
+    case SOCK_OBJECT: {
+      bNodeSocketValueObject *default_value = sock->default_value;
+      FOREACH_CALLBACK_INVOKE_ID_PP(data, (ID **)&default_value->value, IDWALK_CB_USER);
+      break;
+    }
+    case SOCK_IMAGE: {
+      bNodeSocketValueImage *default_value = sock->default_value;
+      FOREACH_CALLBACK_INVOKE_ID_PP(data, (ID **)&default_value->value, IDWALK_CB_USER);
+      break;
+    }
+    case SOCK_FLOAT:
+    case SOCK_VECTOR:
+    case SOCK_RGBA:
+    case SOCK_BOOLEAN:
+    case SOCK_INT:
+    case SOCK_STRING:
+    case __SOCK_MESH:
+    case SOCK_CUSTOM:
+    case SOCK_SHADER:
+      break;
+  }
+
+  FOREACH_FINALIZE_VOID;
+}
+
 static void library_foreach_rigidbodyworldSceneLooper(struct RigidBodyWorld *UNUSED(rbw),
                                                       ID **id_pointer,
                                                       void *user_data,
@@ -1017,7 +1047,6 @@ static void library_foreach_ID_link(Main *bmain,
       case ID_NT: {
         bNodeTree *ntree = (bNodeTree *)id;
         bNode *node;
-        bNodeSocket *sock;
 
         CALLBACK_INVOKE(ntree->gpd, IDWALK_CB_USER);
 
@@ -1025,19 +1054,19 @@ static void library_foreach_ID_link(Main *bmain,
           CALLBACK_INVOKE_ID(node->id, IDWALK_CB_USER);
 
           library_foreach_idproperty_ID_link(&data, node->prop, IDWALK_CB_USER);
-          for (sock = node->inputs.first; sock; sock = sock->next) {
-            library_foreach_idproperty_ID_link(&data, sock->prop, IDWALK_CB_USER);
+          LISTBASE_FOREACH (bNodeSocket *, sock, &node->inputs) {
+            library_foreach_node_socket(&data, sock);
           }
-          for (sock = node->outputs.first; sock; sock = sock->next) {
-            library_foreach_idproperty_ID_link(&data, sock->prop, IDWALK_CB_USER);
+          LISTBASE_FOREACH (bNodeSocket *, sock, &node->outputs) {
+            library_foreach_node_socket(&data, sock);
           }
         }
 
-        for (sock = ntree->inputs.first; sock; sock = sock->next) {
-          library_foreach_idproperty_ID_link(&data, sock->prop, IDWALK_CB_USER);
+        LISTBASE_FOREACH (bNodeSocket *, sock, &ntree->inputs) {
+          library_foreach_node_socket(&data, sock);
         }
-        for (sock = ntree->outputs.first; sock; sock = sock->next) {
-          library_foreach_idproperty_ID_link(&data, sock->prop, IDWALK_CB_USER);
+        LISTBASE_FOREACH (bNodeSocket *, sock, &ntree->outputs) {
+          library_foreach_node_socket(&data, sock);
         }
         break;
       }
diff --git a/source/blender/blenkernel/intern/node.c b/source/blender/blenkernel/intern/node.c
index dea1a5e1cc8..25813fcd98d 100644
--- a/source/blender/blenkernel/intern/node.c
+++ b/source/blender/blenkernel/intern/node.c
@@ -746,6 +746,58 @@ static bNodeSocket *make_socket(bNodeTree *ntree,
   return sock;
 }
 
+static void socket_id_user_increment(bNodeSocket *sock)
+{
+  switch ((eNodeSocketDatatype)sock->type) {
+    case SOCK_OBJECT: {
+      bNodeSocketValueObject *default_value = sock->default_value;
+      id_us_plus(&default_value->value->id);
+      break;
+    }
+    case SOCK_IMAGE: {
+      bNodeSocketValueImage *default_value = sock->default_value;
+      id_us_plus(&default_value->value->id);
+      break;
+    }
+    case SOCK_FLOAT:
+    case SOCK_VECTOR:
+    case SOCK_RGBA:
+    case SOCK_BOOLEAN:
+    case SOCK_INT:
+    case SOCK_STRING:
+    case __SOCK_MESH:
+    case SOCK_CUSTOM:
+    case SOCK_SHADER:
+      break;
+  }
+}
+
+static void socket_id_user_decrement(bNodeSocket *sock)
+{
+  switch ((eNodeSocketDatatype)sock->type) {
+    case SOCK_OBJECT: {
+      bNodeSocketValueObject *default_value = sock->default_value;
+      id_us_min(&default_value->value->id);
+      break;
+    }
+    case SOCK_IMAGE: {
+      bNodeSocketValueImage *default_value = sock->default_value;
+      id_us_min(&default_value->value->id);
+      break;
+    }
+    case SOCK_FLOAT:
+    case SOCK_VECTOR:
+    case SOCK_RGBA:
+    case SOCK_BOOLEAN:
+    case SOCK_INT:
+    case SOCK_STRING:
+    case __SOCK_MESH:
+    case SOCK_CUSTOM:
+    case SOCK_SHADER:
+      break;
+  }
+}
+
 void nodeModifySocketType(
     bNodeTree *ntree, bNode *UNUSED(node), bNodeSocket *sock, int type, int subtype)
 {
@@ -757,6 +809,7 @@ void nodeModifySocketType(
   }
 
   if (sock->default_value) {
+    socket_id_user_decrement(sock);
     MEM_freeN(sock->default_value);
     sock->default_value = NULL;
   }
@@ -860,6 +913,10 @@ const char *nodeStaticSocketType(int type, int subtype)
       return "NodeSocketString";
     case SOCK_SHADER:
       return "NodeSocketShader";
+    case SOCK_OBJECT:
+      return "NodeSocketObject";
+    case SOCK_IMAGE:
+      return "NodeSocketImage";
   }
   return NULL;
 }
@@ -921,6 +978,10 @@ const char *nodeStaticSocketInterfaceType(int type, int subtype)
       return "NodeSocketInterfaceString";
     case SOCK_SHADER:
       return "NodeSocketInterfaceShader";
+    case SOCK_OBJECT:
+      return "NodeSocketInterfaceObject";
+    case SOCK_IMAGE:
+      return "NodeSocketInterfaceImage";
   }
   return NULL;
 }
@@ -979,6 +1040,9 @@ static void node_socket_free(bNodeTree *UNUSED(ntree),
   }
 
   if (sock->default_value) {
+    if (do_id_user) {
+      socket_id_user_decrement(sock);
+    }
     MEM_freeN(sock->default_value);
   }
 }
@@ -1265,6 +1329,10 @@ static void node_socket_copy(bNodeSocket *sock_dst, const bNodeSocket *sock_src,
 
   if (sock_src->default_value) {
     sock_dst->default_value = MEM_dupallocN(sock_src->default_value);
+
+    if ((flag & LIB_ID_CREATE_NO_USER_REFCOUNT) == 0) {
+      socket_id_user_increment(sock_dst);
+    }
   }
 
   sock_dst->stack_index = 0;
@@ -2085,6 +2153,13 @@ void nodeRemoveNode(Main *bmain, bNodeTree *ntree, bNode *node, bool do_id_user)
     if (node->id) {
       id_us_min(node->id);
     }
+
+    LISTBASE_FOREACH (bNodeSocket *, sock, &node->inputs) {
+      socket_id_user_decrement(sock);
+    }
+    LISTBASE_FOREACH (bNodeSocket *, sock, &node->outputs) {
+      socket_id_user_decrement(sock);
+    }
   }
 
   /* Remove animation data. */
@@ -2111,6 +2186,7 @@ static void node_socket_interface_free(bNodeTree *UNUSED(ntree), bNodeSocket *so
   }
 
   if (sock->default_value) {
+    socket_id_user_decrement(sock);
     MEM_freeN(sock->default_value);
   }
 }
diff --git a/source/blender/blenloader/intern/readfile.c b/source/blender/blenloader/intern/readfile.c
index 4dc44548642..6772896b07a 100644
--- a/source/blender/blenloader/intern/readfile.c
+++ b/source/blender/blenloader/intern/readfile.c
@@ -3558,6 +3558,41 @@ static void lib_link_workspace_instance_hook(FileData *fd, WorkSpaceInstanceHook
 /** \name Read ID: Node Tree
  * \{ */
 
+static void lib_link_node_socket(FileData *fd, Library *lib, bNodeSocket *sock)
+{
+  IDP_LibLinkProperty(sock->prop, fd);
+
+  switch ((eNodeSocketDatatype)sock->type) {
+    case SOCK_OBJECT: {
+      bNodeSocketValueObject *default_value = sock->default_value;
+      default_value->value = newlibadr(fd, lib, default_value->value);
+      break;
+    }
+    case SOCK_IMAGE: {
+      bNodeSocketValueImage *default_value = sock->default_value;
+      default_value->value = newlibadr(fd, lib, default_value->value);
+      break;
+    }
+    case SOCK_FLOAT:
+    case SOCK_VECTOR:
+    case SOCK_RGBA:
+    case SOCK_BOOLEAN:
+    case SOCK_INT:
+    case SOCK_STRING:
+    case __SOCK_MESH:
+    case SOCK_CUSTOM:
+    case SOCK_SHADER:
+      break;
+  }
+}
+
+static void lib_link_node_sockets(FileData *fd, Library *lib, ListBase *sockets)
+{
+  LISTBASE_FOREACH (bNodeSocket *, sock, sockets) {
+    lib_link_node_socket(fd, lib, sock);
+  }
+}
+
 /* Single node tree (also used for material/scene trees), ntree is not NULL */
 static void lib_link_ntree(FileData *fd, Library *lib, bNodeTree *ntree)
 {
@@ -3572,20 +3607,12 @@ static void lib_link_ntree(FileData *fd, Library *lib, bNodeTree *ntree)
 
     node->id = newlibadr(fd, lib, node->id);
 
-    LISTBASE_FOREACH (bNodeSocket *, sock, &node->inputs) {
-      IDP_LibLinkProperty(sock->prop, fd);
-    }
-    LISTBASE_FOREACH (bNodeSocket *, sock, &node->outputs) {
-      IDP_LibLinkProperty(sock->prop, fd);
-    }
+    lib_link_node_sockets(fd, lib, &node->inputs);
+    lib_link_node_sockets(fd, lib, &node->outputs);
   }
 
-  LISTBASE_FOREACH (bNodeSocket *, sock, &ntree->inputs) {
-    IDP_LibLinkProperty(sock->prop, fd);
-  }
-  LISTBASE_FOREACH (bNodeSocket *, sock, &ntree->outputs) {
-    IDP_LibLinkProperty(sock->prop, fd);
-  }
+  lib_link_node_sockets(fd, lib, &ntree->inputs);
+  lib_link_node_sockets(fd, lib, &ntree->outputs);
 
   /* Set node->typeinfo pointers. This is done in lib linking, after the
    * first versioning that can change types still without functions that
@@ -10887,10 +10914,47 @@ static void expand_key(FileData *fd, Main *mainvar, Key *key)
   expand_doit(fd, mainvar, key->ipo);  // XXX deprecated - old animation system
 }
 
+static void expand_node_socket(FileData *fd, Main *mainvar, bNodeSocket *sock)
+{
+  expand_idprops(fd, mainvar, sock->prop);
+
+  if (sock->default_value != NULL) {
+
+    switch ((eNodeSocketDatatype)sock->type) {
+      case SOCK_OBJECT: {
+        bNodeSocketValueObject *default_value = sock->default_value;
+        expand_doit(fd, mainvar, default_value->value);
+        break;
+      }
+      case SOCK_IMAGE: {
+        bNodeSocketValueImage *default_value = sock->default_value;
+        expand_doit(fd, mainvar, default_value->value);
+        break;
+      }
+      case SOCK_FLOAT:
+      case SOCK_VECTOR:
+      case SOCK_RGBA:
+      case SOCK_BOOLEAN:
+      case SOCK_INT:
+      case SOCK_STRING:
+      case __SOCK_MESH:
+      case SOCK_CUSTOM:
+      case SOCK_SHADER:
+        break;
+    }
+  }
+}
+
+static void expand_node_sockets(FileData *fd, Main *mainvar, ListBase *sockets)
+{
+  LISTBASE_FOREACH (bNodeSocket *, sock, sockets) {
+    expand_node_socket(fd, mainvar, sock);
+  }
+}
+
 static void expand_nodetree(FileData *fd, Main *mainvar, bNodeTree *ntree)
 {
   bNode *node;
-  bNodeSocket *sock;
 
   if (ntree->gpd) {
     expand_doit(fd, mainvar, ntree->gpd);
@@ -10903,20 +10967,12 @@ static void expand_nodetree(FileData *fd, Main *mainvar, bNodeTree *ntree)
 
     expand_idprops(fd, mainvar, node->prop);
 
-    for (sock = node->inputs.first; sock; sock = sock->next) {
-      expand_idprops(fd, mainvar, sock->prop);
-    }
-    for (sock = node->outputs.first; sock; sock = sock->next) {
-      expand_idprops(fd, mainvar, sock->prop);
-    }
+    expand_node_sockets(fd, mainvar, &node->inputs);
+    expand_node_sockets(fd, mainvar, &node->outputs);
   }
 
-  for (sock = ntree->inputs.first; sock; sock = sock->next) {
-    expand_idprops(fd, mainvar, sock->prop);
-  }
-  for (sock = ntree->outputs.first; sock; sock = sock->next) {
-    expand_idprops(fd, mainvar, sock->prop);
-  }
+  expand_node_sockets(fd, mainvar, &ntree->inputs);
+  expand_node_sockets(fd, mainvar, &ntree->outputs);
 }
 
 static void expand_texture(FileData *fd, Main *mainvar, Tex *tex)
diff --git a/source/blender/blenloader/intern/writefile.c b/source/blender/blenloader/intern/writefile.c
index 40a86297af1..6b0e4db83d7 100644
--- a/source/blender/blenloader/intern/writefile.c
+++ b/source/blender/blenloader/intern/writefile.c
@@ -991,6 +991,12 @@ static void write_node_socket_default_value(WriteData *wd, bNodeSocket *sock)
     case SOCK_STRING:
       writestruct(wd, DATA, bNodeSocketValueString, 1, sock->default_value);
       break;
+    case SOCK_OBJECT:
+      writestruct(wd, DATA, bNodeSocketValueObject, 1, sock->default_value);
+      break;
+    case SOCK_IMAGE:
+      writestruct(wd, DATA, bNodeSocketValueImage, 1, sock->default_value);
+      break;
     case __SOCK_MESH:
     case SOCK_CUSTOM:
     case SOCK_SHADER:
diff --git a/source/blender/editors/space_node/drawnode.c b/source/blender/editors/space_node/drawnode.c
index 01fbafe6176..202e2f2940f 100644
--- a/source/blender/editors/space_node/drawnode.c
+++ b/source/blender/editors/space_node/drawnode.c
@@ -3277,6 +3277,8 @@ static const float std_node_socket_colors[][4] = {
     {0.0, 0.0, 0.0, 1.0},    /*__SOCK_MESH (deprecated) */
     {0.06, 0.52, 0.15, 1.0}, /* SOCK_INT */
     {0.39, 0.39, 0.39, 1.0}, /* SOCK_STRING */
+    {0.40, 0.10, 0.10, 1.0}, /* SOCK_OBJECT */
+    {0.10, 0.40, 0.10, 1.0}, /* SOCK_IMAGE */
 };
 
 /* common color callbacks for standard types */
@@ -3394,6 +3396,14 @@ static void std_node_socket_draw(
       uiItemR(row, ptr, "default_value", 0, "", 0);
       break;
     }
+    case SOCK_OBJECT: {
+      uiItemR(layout, ptr, "default_value", 0, text, 0);
+      break;
+    }
+    case SOCK_IMAGE: {
+      uiItemR(layout, ptr, "default_value", 0, text, 0);
+      break;
+    }
     default:
       node_socket_button_label(C, layout, ptr, node_ptr, text);
       break;
diff --git a/source/blender/makesdna/DNA_node_types.h b/source/blender/makesdna/DNA_node_types.h
index 069449fcba7..bf4d3d2e886 100644
--- a/source/blender/makesdna/DNA_node_types.h
+++ b/source/blender/makesdna/DNA_node_types.h
@@ -154,6 +154,8 @@ typedef enum eNodeSocketDatatype {
   __SOCK_MESH = 5, /* deprecated */
   SOCK_INT = 6,
   SOCK_STRING = 7,
+  SOCK_OBJECT = 8,
+  SOCK_IMAGE = 9,
 } eNodeSocketDatatype;
 
 /* socket shape */
@@ -566,6 +568,14 @@ typedef struct bNodeSocketValueString {
   char value[1024];
 } bNodeSocketValueString;
 
+typedef struct bNodeSocketValueObject {
+  struct Object *value;
+} bNodeSocketValueObject;
+
+typedef struct bNodeSocketValueImage {
+  struct Image *value;
+} bNodeSocketValueImage;
+
 /* data structs, for node->storage */
 enum {
   CMP_NODE_MASKTYPE_ADD = 0,
diff --git a/source/blender/makesrna/intern/rna_nodetree.c b/source/blender/makesrna/intern/rna_nodetree.c
index 4feb53f95bb..abbd6df9693 100644
--- a/source/blender/makesrna/intern/rna_nodetree.c
+++ b/source/blender/makesrna/intern/rna_nodetree.c
@@ -81,6 +81,8 @@ static const EnumPropertyItem node_socket_type_items[] = {
     {SOCK_STRING, "STRING", 0, "String", ""},
     {SOCK_RGBA, "RGBA", 0, "RGBA", ""},
     {SOCK_SHADER, "SHADER", 0, "Shader", ""},
+    {SOCK_OBJECT, "OBJECT", 0, "Object", ""},
+    {SOCK_IMAGE, "IMAGE", 0, "Image", ""},
     {0, NULL, 0, NULL, NULL},
 };
 
@@ -8538,6 +8540,74 @@ static void rna_def_node_socket_virtual(BlenderRNA *brna, const char *identifier
   RNA_def_struct_sdna(srna, "bNodeSocket");
 }
 
+static void rna_def_node_socket_object(BlenderRNA *brna,
+                                       const char *identifier,
+                                       const char *interface_idname)
+{
+  StructRNA *srna;
+  PropertyRNA *prop;
+
+  srna = RNA_def_struct(brna, identifier, "NodeSocketStandard");
+  RNA_def_struct_ui_text(srna, "Object Node Socket", "Object socket of a node");
+  RNA_def_struct_sdna(srna, "bNodeSocket");
+
+  RNA_def_struct_sdna_from(srna, "bNodeSocketValueObject", "default_value");
+
+  prop = RNA_def_property(srna, "default_value", PROP_POINTER, PROP_NONE);
+  RNA_def_property_pointer_sdna(prop, NULL, "value");
+  RNA_def_property_struct_type(prop, "Object");
+  RNA_def_property_ui_text(prop, "Default Value", "Input value used for unconnected socket");
+  RNA_def_property_update(prop, NC_NODE | NA_EDITED, "rna_NodeSocketStandard_value_update");
+  RNA_def_property_flag(prop, PROP_EDITABLE | PROP_ID_REFCOUNT | PROP_CONTEXT_UPDATE);
+
+  /* socket interface */
+  srna = RNA_def_struct(brna, interface_idname, "NodeSocketInterfaceStandard");
+  RNA_def_struct_ui_text(srna, "Object Node Socket Interface", "Object socket of a node");
+  RNA_def_struct_sdna(srna, "bNodeSocket");
+
+  RNA_def_struct_sdna_from(srna, "bNodeSocketValueObject", "default_value");
+
+  prop = RNA_def_property(srna, "default_value", PROP_POINTER, PROP_NONE);
+  RNA_def_property_pointer_sdna(prop, NULL, "value");
+  RNA_def_property_struct_type(prop, "Object");
+  RNA_def_property_ui_text(prop, "Default Value", "Input value used for unconnected socket");
+  RNA_def_property_update(prop, NC_NODE | NA_EDITED, "rna_NodeSocketInterface_update");
+}
+
+static void rna_def_node_socket_image(BlenderRNA *brna,
+                                      const char *identifier,
+                                      const char *interface_idname)
+{
+  StructRNA *srna;
+  PropertyRNA *prop;
+
+  srna = RNA_def_struct(brna, identifier, "NodeSocketStandard");
+  RNA_def_struct_ui_text(srna, "Image Node Socket", "Image socket of a node");
+  RNA_def_struct_sdna(srna, "bNodeSocket");
+
+  RNA_def_struct_sdna_from(srna, "bNodeSocketValueImage", "default_value");
+
+  prop = RNA_def_property(srna, "default_value", PROP_POINTER, PROP_NONE);
+  RNA_def_property_pointer_sdna(prop, NULL, "value");
+  RNA_def_property_struct_type(prop, "Image");
+  RNA_def_property_ui_text(prop, "Default Value", "Input value used for unconnected socket");
+  RNA_def_property_update(prop, NC_NODE | NA_EDITED, "rna_NodeSocketStandard_value_update");
+  RNA_def_property_flag(prop, PROP_EDITABLE | PROP_ID_REFCOUNT | PROP_CONTEXT_UPDATE);
+
+  /* socket interface */
+  srna = RNA_def_struct(brna, interface_idname, "NodeSocketInterfaceStandard");
+  RNA_def_struct_ui_text(srna, "Image Node Socket Interface", "Image socket of a node");
+  RNA_def_struct_sdna(srna, "bNodeSocket");
+
+  RNA_def_struct_sdna_from(srna, "bNodeSocketValueImage", "default_value");
+
+  prop = RNA_def_property(srna, "default_value", PROP_POINTER, PROP_NONE);
+  RNA_def_property_pointer_sdna(prop, NULL, "value");
+  RNA_def_property_struct_type(prop, "Image");
+  RNA_def_property_ui_text(prop, "Default Value", "Input value used for unconnected socket");
+  RNA_def_property_update(prop, NC_NODE | NA_EDITED, "rna_NodeSocketInterface_update");
+}
+
 static void rna_def_node_socket_standard_types(BlenderRNA *brna)
 {
   /* XXX Workaround: Registered functions are not exposed in python by bpy,
@@ -8672,6 +8742,10 @@ static void rna_def_node_socket_standard_types(BlenderRNA *brna)
   rna_def_node_socket_shader(brna, "NodeSocketShader", "NodeSocketInterfaceShader");
 
   rna_def_node_socket_virtual(brna, "NodeSocketVirtual");
+
+  rna_def_node_socket_object(brna, "NodeSocketObject", "NodeSocketInterfaceObject");
+
+  rna_def_node_socket_image(brna, "NodeSocketImage", "NodeSocketInterfaceImage");
 }
 
 static void rna_def_internal_node(BlenderRNA *brna)
diff --git a/source/blender/nodes/intern/node_socket.c b/source/blender/nodes/intern/node_socket.c
index 199b469781d..af492c42d78 100644
--- a/source/blender/nodes/intern/node_socket.c
+++ b/source/blender/nodes/intern/node_socket.c
@@ -259,6 +259,22 @@ void node_socket_init_default_value(bNodeSocket *sock)
       sock->default_value = dval;
       break;
     }
+    case SOCK_OBJECT: {
+      bNodeSocketValueObject *dval = MEM_callocN(sizeof(bNodeSocketValueObject),
+                                                 "node socket value object");
+      dval->value = NULL;
+
+      sock->default_value = dval;
+      break;
+    }
+    case SOCK_IMAGE: {
+      bNodeSocketValueImage *dval = MEM_callocN(sizeof(bNodeSocketValueImage),
+                                                "node socket value image");
+      dval->value = NULL;
+
+      sock->default_value = dval;
+      break;
+    }
   }
 }
 
@@ -317,6 +333,18 @@ void node_socket_copy_default_value(bNodeSocket *to, const bNodeSocket *from)
       *toval = *fromval;
       break;
     }
+    case SOCK_OBJECT: {
+      /* Not sure how to handle user count here yet. For now just don't copy the pointer. */
+      bNodeSocketValueObject *toval = to->default_value;
+      toval->value = NULL;
+      break;
+    }
+    case SOCK_IMAGE: {
+      /* Not sure how to handle user count here yet. For now just don't copy the pointer. */
+      bNodeSocketValueImage *toval = to->default_value;
+      toval->value = NULL;
+      break;
+    }
   }
 
   to->flag |= (from->flag & SOCK_HIDE_VALUE);
@@ -499,5 +527,9 @@ void register_standard_node_socket_types(void)
 
   nodeRegisterSocketType(make_standard_socket_type(SOCK_SHADER, PROP_NONE));
 
+  nodeRegisterSocketType(make_standard_socket_type(SOCK_OBJECT, PROP_NONE));
+
+  nodeRegisterSocketType(make_standard_socket_type(SOCK_IMAGE, PROP_NONE));
+
   nodeRegisterSocketType(make_socket_type_virtual());
 }