/// <summary>
    /// 画面更新时调用一次,主线程
    /// 暂停时也会持续调用,谱面尚未加载时也会持续调用,下同
    /// 画面更新 是指 Unity显示层(以玩家眼中的游戏画面为准)更新,距离上次调用的时间为 UnityEngine.Time.deltaTime
    /// 当前歌曲播放的进度(秒)为 TentacleGuitarUnity.Stage.Time,暂停时持续刷新同一个秒数
    /// 请适当 cache 节约性能
    /// </summary>
    public static void StageLateUpdate()
    {
        if (Stage.GamePlaying && StageMusic.Main.IsReady && StageMusic.Main.IsPlaying && CurrentNoteNum > 0)
        {
            float time = StageMusic.Main.Time;

            for (; CurrentLoadedIndex < Notes.Count; CurrentLoadedIndex++)
            {
                float noteTime = Notes[CurrentLoadedIndex].Time;
                if (noteTime > time + CurrentShowNoteTime)
                {
                    break;
                }
                else
                {
                    Stage.AddNote(Notes[CurrentLoadedIndex]);
                }
            }


            int    minX          = 23;
            int    maxX          = 0;
            bool[] stringLighted = new bool[6];
            for (int i = 0; i < Stage.NotePool.Count; i++)
            {
                Note n = Stage.NotePool[i].GetComponent <Note>();
                if (n)
                {
                    minX = Mathf.Min(minX, n.X);
                    maxX = Mathf.Max(maxX, n.X);
                    stringLighted[n.Y] = true;
                }
            }
            if (Stage.NotePool.Count > 0)
            {
                Stage.MoveCamera((int)(0.5f * (minX + maxX)));
                for (int i = 0; i < 24; i++)
                {
                    Stage.SetTrackHightLight(i, i >= minX && i <= maxX);
                    Stage.SetFretWireLight(i, i >= minX && i - 1 <= maxX);
                }
                for (int i = 0; i < 6; i++)
                {
                    Stage.SetStringLight(i, stringLighted[i]);
                }
            }
        }
    }