Index: trunk/src/buffer.c
===================================================================
--- trunk/src/buffer.c	(revision 9145)
+++ trunk/src/buffer.c	(revision 9146)
@@ -112,7 +112,7 @@
 		Buffer->Data->parent.any = old_parent;
 		Buffer->Data->parent_type = old_pt;
 		if (pcb != NULL)
-			pcb_data_bind_board_layers(pcb, Buffer->Data);
+			pcb_data_bind_board_layers(pcb, Buffer->Data, 0);
 	}
 }
 
Index: trunk/src/data.c
===================================================================
--- trunk/src/data.c	(revision 9145)
+++ trunk/src/data.c	(revision 9146)
@@ -348,11 +348,11 @@
 		data->Layer[n].parent = data;
 }
 
-void pcb_data_bind_board_layers(pcb_board_t *pcb, pcb_data_t *data)
+void pcb_data_bind_board_layers(pcb_board_t *pcb, pcb_data_t *data, int share_rtrees)
 {
 	pcb_layer_id_t n;
 	for(n = 0; n < PCB_MAX_LAYER; n++) {
-		pcb_layer_real2bound(&data->Layer[n], &pcb->Data->Layer[n]);
+		pcb_layer_real2bound(&data->Layer[n], &pcb->Data->Layer[n], share_rtrees);
 		data->Layer[n].parent = data;
 	}
 }
Index: trunk/src/data.h
===================================================================
--- trunk/src/data.h	(revision 9145)
+++ trunk/src/data.h	(revision 9146)
@@ -128,7 +128,7 @@
 void pcb_data_set_layer_parents(pcb_data_t *data);
 
 /* Set up all data layers as bound layers to pcb's Data */
-void pcb_data_bind_board_layers(pcb_board_t *pcb, pcb_data_t *data);
+void pcb_data_bind_board_layers(pcb_board_t *pcb, pcb_data_t *data, int share_rtrees);
 
 
 /* Returns the top level pcb related to a data, or NULL if the data is floating
Index: trunk/src/layer.c
===================================================================
--- trunk/src/layer.c	(revision 9145)
+++ trunk/src/layer.c	(revision 9146)
@@ -620,7 +620,7 @@
 	return NULL;
 }
 
-void pcb_layer_real2bound(pcb_layer_t *dst, pcb_layer_t *src)
+void pcb_layer_real2bound(pcb_layer_t *dst, pcb_layer_t *src, int share_rtrees)
 {
 	dst->grp = src->grp;
 	dst->comb = src->comb;
@@ -627,10 +627,12 @@
 
 	if (PCB_LAYER_IS_REAL(src)) {
 		dst->meta.bound.real = src;
-		dst->line_tree = src->line_tree;
-		dst->text_tree = src->text_tree;
-		dst->polygon_tree = src->polygon_tree;
-		dst->subc_tree = src->subc_tree;
+		if (share_rtrees) {
+			dst->line_tree = src->line_tree;
+			dst->text_tree = src->text_tree;
+			dst->polygon_tree = src->polygon_tree;
+			dst->subc_tree = src->subc_tree;
+		}
 	}
 	else
 		dst->meta.bound.real = NULL;
Index: trunk/src/layer.h
===================================================================
--- trunk/src/layer.h	(revision 9145)
+++ trunk/src/layer.h	(revision 9146)
@@ -244,7 +244,7 @@
 
 
 /* Set up dst so that it's a non-real layer bound to src */
-void pcb_layer_real2bound(pcb_layer_t *dst, pcb_layer_t *src);
+void pcb_layer_real2bound(pcb_layer_t *dst, pcb_layer_t *src, int share_rtrees);
 
 
 /* list of virtual layers: these are generated by the draw code but do not