diff --git a/doomsday/libdeng2/include/de/core/vector.h b/doomsday/libdeng2/include/de/core/vector.h
index be3e0d9f15..7cf9f47af3 100644
--- a/doomsday/libdeng2/include/de/core/vector.h
+++ b/doomsday/libdeng2/include/de/core/vector.h
@@ -169,6 +169,9 @@ class Vector2
     ddouble length() const {
         return std::sqrt(ddouble(x*x + y*y));
     }
+    void setLength(ddouble len) {
+        *this = *this / length() * len;
+    }
     Vector2 normalize() const {
         ddouble const len = length();
         if(len != 0) {
@@ -353,6 +356,9 @@ class Vector3 : public Vector2<Type>
     inline ddouble length() const {
         return std::sqrt(lengthSquared());
     }
+    void setLength(ddouble len) {
+        *this = *this / length() * len;
+    }
     ddouble lengthSquared() const {
         return Vector2<Type>::x*Vector2<Type>::x + Vector2<Type>::y*Vector2<Type>::y + z*z;
     }