stock GetVehicleRelativePos(vehicleid, &Float:x, &Float:y, &Float:z, Float:xoff=0.0, Float:yoff=0.0, Float:zoff=0.0)
{
    new Float:rot;
    GetVehicleZAngle(targetid, rot);
    rot = 360 - rot;    // Making the vehicle rotation compatible with pawns sin/cos
    GetVehiclePos(vehicleid, x, y, z);
    x = floatsin(rot,degrees) * yoff + floatcos(rot,degrees) * xoff + x;
    y = floatcos(rot,degrees) * yoff - floatsin(rot,degrees) * xoff + y;
    z = zoff + z;

    /*
       where xoff/yoff/zoff are the offsets relative to the vehicle
       x/y/z then are the coordinates of the point with the given offset to the vehicle
       xoff = 1.0 would e.g. point to the right side of the vehicle, -1.0 to the left, etc.
    */
}