[gegl] bin: add ability to clone parts of graph

[Øyvind "pippin" Kolås <ok src gnome org>]

commit e9a5ef2b00540419e6dfc918c48d36a5176309dd
Author: Øyvind Kolås <pippin gimp org>
Date:   Sat Jan 19 22:47:44 2019 +0100

    bin: add ability to clone parts of graph
    
    This continus the use of similar or side-effect behavior of the
    traditional copy paste keybindings in addition to control-x - which
    already is used for removing nodes (it doesn't store them to a clipboard however).
    
    now control-c stores a pointer to the active node and control-v uses the
    pointer on the input port, or if aux port is active on aux port of a node, this
    permits rigging up custom implementations of unsharp mask and drop-shadow from
    primitive gegl nodes from scratch when using keybindings.

 bin/ui.c | 36 +++++++++++++++++++++++++++++++++++-
 1 file changed, 35 insertions(+), 1 deletion(-)
---
diff --git a/bin/ui.c b/bin/ui.c
index b04d1c4a0..38ebbdc81 100644
--- a/bin/ui.c
+++ b/bin/ui.c
@@ -210,6 +210,8 @@ struct _State {
 
   int            show_bindings;
 
+  GeglNode      *reference_node;
+
   GeglNode      *processor_node; /* the node we have a processor for */
   GeglProcessor *processor;
   GeglBuffer    *processor_buffer;
@@ -1257,6 +1259,33 @@ cmd_todo (COMMAND_ARGS)
   return 0;
 }
 
+int cmd_reference (COMMAND_ARGS);/* "reference", -1, "", ""*/
+int
+cmd_reference (COMMAND_ARGS)
+{
+  State *o = global_state;
+  o->reference_node = o->active;
+  return 0;
+}
+
+int cmd_dereference (COMMAND_ARGS);/* "dereference", -1, "", ""*/
+int
+cmd_dereference (COMMAND_ARGS)
+{
+  State *o = global_state;
+  switch (o->pad_active)
+  {
+    case 0:
+    case 2:
+      gegl_node_link_many (o->reference_node, o->active, NULL);
+      break;
+    case 1:
+      gegl_node_link_many (o->reference_node, o->active, NULL);
+      break;
+  }
+  return 0;
+}
+
 
 int cmd_mipmap (COMMAND_ARGS);/* "mipmap", -1, "", ""*/
 
@@ -3071,8 +3100,8 @@ static void ui_commandline (Mrg *mrg, void *data)
     mrg_edit_start (mrg, update_commandline, o);
     mrg_printf (mrg, "%s", commandline);
     mrg_edit_end (mrg);
-    mrg_end (mrg);
   mrg_edit_end (mrg);
+    mrg_end (mrg);
   row++;
 
   //mrg_set_xy (mrg, em, h * 0.5);
@@ -3237,6 +3266,11 @@ static void gegl_ui (Mrg *mrg, void *data)
     if (o->active != o->source)
       mrg_add_binding (mrg, "control-x", NULL, NULL, run_command, "remove");
 
+    if (o->active != o->source)
+      mrg_add_binding (mrg, "control-c", NULL, NULL, run_command, "reference");
+
+    mrg_add_binding (mrg, "control-v", NULL, NULL, run_command, "dereference");
+
     mrg_add_binding (mrg, "control-s", NULL, NULL, run_command, "toggle slideshow");
   }
   mrg_add_binding (mrg, "control-l", NULL, NULL, run_command, "clear");