var callback = self.model.layer[current_layer].allowed_edges[source_type].destination[destination_type].removable.callback;
var c = self.model.callback[callback].class;
var controller = new TCD3.OsmController();
var callback = self.model.layer[current_layer].allowed_edges[source_type].destination[destination_type].removable.callback;
var c = self.model.callback[callback].class;
var controller = new TCD3.OsmController();