const float M_2_SQRTPI = 1.12837916709551257390; /* 2/sqrt(pi) */
const float M_SQRT2 = 1.41421356237309504880; /* sqrt(2) */
const float M_SQRT1_2 = 0.70710678118654752440; /* 1/sqrt(2) */
+
+// Non-<math.h> stuff follows here.
+vector cross(vector a, vector b);
+
#endif