VEC3 cross(const VEC3& a, const VEC3& b)
{
float x = (a.y()*b.z())-(b.y()*a.z());
float y = (a.z()*b.x())-(b.z()*b.x());
float z = (a.x()*b.y())-(b.x()*a.y());
return (VEC3(x, y, z));
}
VEC3 operator* (const float scalar, VEC3& v)
{
return(VEC3(scalar * v.x(), scalar * v.y(), scalar * v.z()));
}