diff --git a/dump.c b/dump.c
index 12972a3..1493f39 100644
--- a/dump.c
+++ b/dump.c
@@ -296,8 +296,12 @@ static void generate_name(struct vec *base)
 
 static const char *base_name(struct vec *base, const struct vec *next)
 {
+	const char *name = (const char *) base;
+
 	if (!base)
 		return "@";
+	if (*name)
+		return name;
 	if (next && base->next == next)
 		return ".";
 	if (!base->name)
diff --git a/fpd.y b/fpd.y
index f66830f..8782ed2 100644
--- a/fpd.y
+++ b/fpd.y
@@ -826,6 +826,7 @@ vec:
 	TOK_VEC base '(' expr ',' expr ')'
 		{
 			$$ = alloc_type(struct vec);
+			$$->nul_tag = 0;
 			$$->name = NULL;
 			$$->base = $2;
 			$$->x = $4;
@@ -854,10 +855,8 @@ base:
 	| ID
 		{
 			$$ = find_vec(curr_frame, $1);
-			if (!$$) {
-				yyerrorf("unknown vector \"%s\"", $1);
-				YYABORT;
-			}
+			if (!$$)
+				$$ = (struct vec *) $1;
 		}
 	;
 
diff --git a/gui_tool.c b/gui_tool.c
index 799d16d..05f6506 100644
--- a/gui_tool.c
+++ b/gui_tool.c
@@ -1,8 +1,8 @@
 /*
  * gui_tool.c - GUI, tool bar
  *
- * Written 2009, 2010 by Werner Almesberger
- * Copyright 2009, 2010 by Werner Almesberger
+ * Written 2009-2011 by Werner Almesberger
+ * Copyright 2009-2011 by Werner Almesberger
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -73,6 +73,7 @@ static struct vec *new_vec(struct inst *base)
 	struct vec *vec, **walk;
 
 	vec = alloc_type(struct vec);
+	vec->nul_tag = 0;
 	vec->name = NULL;
 	vec->base = inst_get_vec(base);
 	vec->next = NULL;
diff --git a/obj.c b/obj.c
index 72953e6..ee2e73a 100644
--- a/obj.c
+++ b/obj.c
@@ -168,11 +168,39 @@ static struct num eval_unit_default(const struct expr *expr,
 }
 
 
-static int resolve_vec(const struct vec *vec, struct coord base_pos,
+static int recurse_vec(const char *name, const struct frame *frame,
     struct coord *res)
 {
-	*res = vec ? vec->pos : base_pos;
-	return 1;
+	const struct vec *v;
+
+	if (!frame)
+		return 0;
+	for (v = frame->vecs; v; v = v->next)
+		if (v->name == name) {
+			*res = v->pos;
+			return 1;
+		}
+	return recurse_vec(name, frame->curr_parent, res);
+}
+
+
+static int resolve_vec(const struct vec *vec, struct coord base_pos,
+    const struct frame *frame, struct coord *res)
+{
+	const char *name = (const char *) vec;
+
+	if (!vec) {
+		*res = base_pos;
+		return 1;
+	}
+	if (!*name) {
+		*res = vec->pos;
+		return 1;
+	}
+	if (recurse_vec(name, frame->curr_parent, res))
+		return 1;
+	fail("unknown vector \"%s\"", name);
+	return 0;
 }
 
 
@@ -189,7 +217,7 @@ static int generate_vecs(struct frame *frame, struct coord base_pos)
 		y = eval_unit(vec->y, frame);
 		if (is_undef(y))
 			goto error;
-		if (!resolve_vec(vec->base, base_pos, &vec_base))
+		if (!resolve_vec(vec->base, base_pos, frame, &vec_base))
 			goto error;
 		vec->pos = vec_base;
 		vec->pos.x += x.n;
@@ -217,7 +245,7 @@ static int generate_objs(struct frame *frame, struct coord base_pos,
 
 	for (obj = frame->objs; obj; obj = obj->next) {
 		if (obj->type != ot_meas)
-			if (!resolve_vec(obj->base, base_pos, &base))
+			if (!resolve_vec(obj->base, base_pos, frame, &base))
 				goto error;
 		switch (obj->type) {
 		case ot_frame:
@@ -226,7 +254,8 @@ static int generate_objs(struct frame *frame, struct coord base_pos,
 				return 0;
 			break;
 		case ot_line:
-			if (!resolve_vec(obj->u.line.other, base_pos, &other))
+			if (!resolve_vec(obj->u.line.other, base_pos, frame,
+			    &other))
 				goto error;
 			width = eval_unit_default(obj->u.line.width, frame,
 			    DEFAULT_SILK_WIDTH);
@@ -236,7 +265,8 @@ static int generate_objs(struct frame *frame, struct coord base_pos,
 				goto error;
 			break;
 		case ot_rect:
-			if (!resolve_vec(obj->u.rect.other, base_pos, &other))
+			if (!resolve_vec(obj->u.rect.other, base_pos, frame,
+			    &other))
 				goto error;
 			width = eval_unit_default(obj->u.rect.width, frame,
 			    DEFAULT_SILK_WIDTH);
@@ -246,7 +276,8 @@ static int generate_objs(struct frame *frame, struct coord base_pos,
 				goto error;
 			break;
 		case ot_pad:
-			if (!resolve_vec(obj->u.pad.other, base_pos, &other))
+			if (!resolve_vec(obj->u.pad.other, base_pos, frame,
+			    &other))
 				goto error;
 			name = expand(obj->u.pad.name, frame);
 			if (!name)
@@ -257,15 +288,18 @@ static int generate_objs(struct frame *frame, struct coord base_pos,
 				goto error;
 			break;
 		case ot_hole:
-			if (!resolve_vec(obj->u.hole.other, base_pos, &other))
+			if (!resolve_vec(obj->u.hole.other, base_pos, frame,
+			    &other))
 				goto error;
 			if (!inst_hole(obj, base, other))
 				goto error;
 			break;
 		case ot_arc:
-			if (!resolve_vec(obj->u.arc.start, base_pos, &start))
+			if (!resolve_vec(obj->u.arc.start, base_pos, frame,
+			    &start))
 				goto error;
-			if (!resolve_vec(obj->u.arc.end, base_pos, &end))
+			if (!resolve_vec(obj->u.arc.end, base_pos, frame,
+			    &end))
 				goto error;
 			width = eval_unit_default(obj->u.arc.width, frame,
 			    DEFAULT_SILK_WIDTH);
diff --git a/obj.h b/obj.h
index 27d2dca..dd901c1 100644
--- a/obj.h
+++ b/obj.h
@@ -1,8 +1,8 @@
 /*
  * obj.h - Object definition model
  *
- * Written 2009, 2010 by Werner Almesberger
- * Copyright 2009, 2010 by Werner Almesberger
+ * Written 2009-2011 by Werner Almesberger
+ * Copyright 2009-2011 by Werner Almesberger
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -125,6 +125,7 @@ struct loop {
 struct sample;
 
 struct vec {
+	char nul_tag;	/* tag for identifying vectors */
 	const char *name; /* NULL if anonymous */
 	struct expr *x;
 	struct expr *y;