private void MoveBullet(float deltaTime)
    {
        var curPos  = trans.position;
        var nextPos = curPos + direction * deltaTime * speed;

        BulletManager.CalculateBulletPos(curPos, ref nextPos, ref direction);
        trans.position = nextPos;
        trans.up       = Vector3.forward;
        trans.forward  = direction;
    }