Index: trunk/src/obj_subc.c
===================================================================
--- trunk/src/obj_subc.c	(revision 32725)
+++ trunk/src/obj_subc.c	(revision 32726)
@@ -853,6 +853,25 @@
 	pcb_subc_draw_origin(pcb_crosshair.GC, sc, DX, DY);
 }
 
+pcb_layer_t *pcb_subc_alloc_layer_like(pcb_subc_t *subc, const pcb_layer_t *sl)
+{
+	pcb_layer_t *dl;
+
+	if (subc->data->LayerN >= PCB_MAX_LAYER)
+		return NULL;
+
+	dl = &subc->data->Layer[subc->data->LayerN++];
+	dl->is_bound = 1;
+	dl->type = PCB_OBJ_LAYER;
+	memcpy(&dl->meta.bound, &sl->meta.bound, sizeof(sl->meta.bound));
+	dl->name = rnd_strdup(sl->name);
+	dl->comb = sl->comb;
+	if (dl->meta.bound.real != NULL)
+		pcb_layer_link_trees(dl, dl->meta.bound.real);
+
+	return dl;
+}
+
 #define MAYBE_KEEP_ID(dst, src) \
 do { \
 	if ((keep_ids) && (dst != NULL)) \
Index: trunk/src/obj_subc.h
===================================================================
--- trunk/src/obj_subc.h	(revision 32725)
+++ trunk/src/obj_subc.h	(revision 32726)
@@ -175,6 +175,10 @@
 /* Copy layer objects from source layer sl to destination layer dl into dst_sc */
 void pcb_subc_dup_layer_objs(pcb_subc_t *dst_sc, pcb_layer_t *dl, pcb_layer_t *sl, rnd_coord_t dx, rnd_coord_t dy, rnd_bool keep_ids);
 
+/* Allocate and return a new layer in subc, copying binding and basic
+   properties from another subc layer (potentially from another subc) from sl */
+pcb_layer_t *pcb_subc_alloc_layer_like(pcb_subc_t *subc, const pcb_layer_t *sl);
+
 /*** subc creation helpers ***/
 
 /* Create the aux layer for a subc, set origin to ox;oy and rotation to rot */