屏幕空间伤害弹字，根据攻击角度调整弹字方向。

  　　　　　　Vector3 screen= Camera.main.WorldToScreenPoint(transform.position+Vector3.up*0.2f);
            GameObject gameObject = GameObject.Instantiate(damageText);
            TMP_Text text = gameObject.GetComponentInChildren<TMP_Text>();
            text.text = "-" + ((int)damage).ToString();
            //Destroy(gameObject, 1f);
            Transform textTrans = gameObject.transform.GetChild(0);
            screen.z = 0;
            textTrans.position = screen;
            Vector3 dir = collision.transform.position - transform.position;
            dir.Normalize();
            float d= Vector3.Dot(collision.transform.parent.right,dir);
            Vector3 temp = new Vector3(-d*Screen.width*0.5f,Random.Range(0.5f, 1f)*Screen.height*0.5f,0);
            (textTrans as RectTransform).DOLocalMove(temp, 0.8f).SetEase(Ease.OutBack);
            text.DOFade(0, 0.5f).SetEase(Ease.OutCirc).SetDelay(0.3f);
            textTrans.DOScale(1.5f,0.8f).SetEase(Ease.OutCirc);