public void OnReleased()
{
isTouched = false;
Vector3 touchPos = MathUtil.ScreenPos_to_NGUIPos(Input.mousePosition);
Vector3 from = touchPos - new Vector3(0, -315);
float angle = Vector3.Angle(from, Vector3.right);
cannon.transform.eulerAngles = new Vector3(0, 0, angle);
cannon.FireAction();
return;
Bullet bullet = (Instantiate(Resources.Load("BulletPrefabs/Bullet")) as GameObject).GetComponent <Bullet>();
bullet.Angle = cannon.transform.eulerAngles.z;
bullet.transform.parent = UIManager.GetInstance().WeaponRoot;
bullet.transform.localPosition = cannon.transform.localPosition + from.normalized * 50;
bullet.transform.localScale = Vector3.one;
}