Index: trunk/src/data.c
===================================================================
--- trunk/src/data.c	(revision 18892)
+++ trunk/src/data.c	(revision 18893)
@@ -337,6 +337,13 @@
 	}
 }
 
+void pcb_data_unbind_layers(pcb_data_t *data)
+{
+	pcb_layer_id_t n;
+	for(n = 0; n < data->LayerN; n++)
+		data->Layer[n].meta.bound.real = NULL;
+}
+
 void pcb_data_binding_update(pcb_board_t *pcb, pcb_data_t *data)
 {
 	int i;
Index: trunk/src/data.h
===================================================================
--- trunk/src/data.h	(revision 18892)
+++ trunk/src/data.h	(revision 18893)
@@ -138,6 +138,9 @@
 /* Recalculate the layer bindings updating meta.bound.real to new board layers */
 void pcb_data_binding_update(pcb_board_t *pcb, pcb_data_t *data);
 
+/* Break the binding in data bound layers (set htem all to NULL) */
+void pcb_data_unbind_layers(pcb_data_t *data);
+
 /* Make sure there are no negative coords in data, knowing the bbox of the data */
 int pcb_data_normalize_(pcb_data_t *data, pcb_box_t *data_bbox);