This is easy to do in c-script, but it would be much easier if it were built into the engine.

A Function for inversely rotating vectors. This makes it possible to convert world-space offsets to local-offsets. Here's what I've been using:

Code:

---

Function vec_iRotate(&_vec, &_ang)
{
    var tAng[3];
    vec_set(tAng, _ang);
    vec_inverse(tAng);
    vec_rotate(_vec, tAng);
}

---