diff --git a/src/corelib/math/vec.h b/src/corelib/math/vec.h
index 9a62b93..1129da3 100644
--- a/src/corelib/math/vec.h
+++ b/src/corelib/math/vec.h
@@ -25,6 +25,14 @@ void normalize(float* xx, float* yy) {
 	}
 }
 
+#define NORMALIZE(_xx, _yy) \
+if(_xx != 0 || _yy != 0) { \
+	const float m = sqrtf(_xx*_xx + _yy*_yy); \
+	_xx /= m; _yy /= m; \
+} else { \
+	_xx = 0; _yy = 0; \
+}
+
 static inline
 int move_towards(float* out_x, float* out_y, float x, float y, float tx, float ty, float max_delta) {
 	const float diff_x = tx - x,