Index: trunk/src/obj_line.c
===================================================================
--- trunk/src/obj_line.c	(revision 18573)
+++ trunk/src/obj_line.c	(revision 18574)
@@ -365,7 +365,25 @@
 	y[3] = (pcb_coord_t)pcb_round(y2 + vy * width + ny * width);
 }
 
+void pcb_line_pre(pcb_line_t *line)
+{
+	pcb_layer_t *ly = pcb_layer_get_real(line->parent.layer);
+	if (ly == NULL)
+		return;
+	if (ly->line_tree != NULL)
+		pcb_r_delete_entry(ly->line_tree, (pcb_box_t *)line);
+	pcb_poly_restore_to_poly(ly->parent.data, PCB_OBJ_LINE, ly, line);
+}
 
+void pcb_line_post(pcb_line_t *line)
+{
+	pcb_layer_t *ly = pcb_layer_get_real(line->parent.layer);
+	if (ly == NULL)
+		return;
+	if (ly->line_tree != NULL)
+		pcb_r_insert_entry(ly->line_tree, (pcb_box_t *)line);
+	pcb_poly_clear_from_poly(ly->parent.data, PCB_OBJ_LINE, ly, line);
+}
 
 /*** ops ***/
 /* copies a line to buffer */
Index: trunk/src/obj_line.h
===================================================================
--- trunk/src/obj_line.h	(revision 18573)
+++ trunk/src/obj_line.h	(revision 18574)
@@ -77,7 +77,12 @@
 int pcb_line_eq(const pcb_host_trans_t *tr1, const pcb_line_t *l1, const pcb_host_trans_t *tr2, const pcb_line_t *l2);
 unsigned int pcb_line_hash(const pcb_host_trans_t *tr, const pcb_line_t *l);
 
+/* un-administrate a line; call before changing geometry */
+void pcb_line_pre(pcb_line_t *line);
 
+/* re-administrate a line; call after changing geometry */
+void pcb_line_pre(pcb_line_t *line);
+
 /*** DRC enforcement (obj_line_drcenf.c) ***/
 void pcb_line_adjust_attached(void);
 void pcb_line_adjust_attached_2lines(pcb_bool);