diff --git a/libs/geom/include/psemek/geom/box.hpp b/libs/geom/include/psemek/geom/box.hpp
index faf6baed..95ae7655 100644
--- a/libs/geom/include/psemek/geom/box.hpp
+++ b/libs/geom/include/psemek/geom/box.hpp
@@ -252,10 +252,26 @@ namespace psemek::geom
 		return b;
 	}
 
+	template <typename T, std::size_t N>
+	box<T, N> expand(box<T, N> b, vector<T, N> const & d)
+	{
+		for (std::size_t i = 0; i < N; ++i)
+		{
+			b[i] = expand(b[i], d[i]);
+		}
+		return b;
+	}
+
 	template <typename T, std::size_t N>
 	box<T, N> shrink(box<T, N> b, T const & d)
 	{
 		return expand(b, -d);
 	}
 
+	template <typename T, std::size_t N>
+	box<T, N> shrink(box<T, N> b, vector<T, N> const & d)
+	{
+		return expand(b, -d);
+	}
+
 }