diff --git a/src/libslic3r/libslic3r.h b/src/libslic3r/libslic3r.h
index 4480c3e88..922a8a45f 100644
--- a/src/libslic3r/libslic3r.h
+++ b/src/libslic3r/libslic3r.h
@@ -86,6 +86,7 @@ template<typename T, typename Q>
 inline T unscale(Q v) { return T(v) * T(SCALING_FACTOR); }
 
 inline double unscaled(double v) { return v * SCALING_FACTOR; }
+inline coordf_t unscale_(coord_t v) { return v * SCALING_FACTOR; }
 
 enum Axis { X=0, Y, Z, E, F, NUM_AXES };