public float moveSpeed = 3f;//指的是在unity里的移動(dòng)速度
 // Update is called once per frame
 void Update()
 {
  this.transform.Translate(Vector3.down * moveSpeed *Time.deltaTime);
  Vector3 vector3 = this.transform.position;
  //表示背景已經(jīng)出了游戲相機(jī)的邊框
  if (vector3.y <= -8.52f)
  {
   //將其移到上面的游戲背景區(qū),如果是-vector3.y會(huì)導(dǎo)致兩張圖片之間有空隙無(wú)法達(dá)到輪播的效果
   this.transform.position = new Vector3(vector3.x, vector3.y+8.52f*2, vector3.z);
  }

//判斷動(dòng)畫(huà)是否繼續(xù)，因?yàn)槿绻麜和Ａ擞螒?，就可以不進(jìn)行動(dòng)畫(huà)
public bool animation = true;
//每秒播放幾幀
public int frameCountPreSeconds = 10;
 //計(jì)時(shí)器
 public float timer = 0;                  
 //播放幀的數(shù)組
 public Sprite[] sprites;
 private SpriteRenderer SpriteRenderer;
 // Start is called before the first frame update
 void Start()
 {
  SpriteRenderer = this.GetComponent<SpriteRenderer>();
 }

 // Update is called once per frame
 void Update()
 {
  if (animation) {
   timer += Time.deltaTime;
   //1f/frameCountPreSeconds 每一幀的時(shí)間間隔     
   int frameIndex =(int) (timer /(1f/ frameCountPreSeconds));
   //當(dāng)前應(yīng)當(dāng)播放的是哪一幀
   int frame = frameIndex % 2;
   //首先先獲取組件SpriteRenderer，再獲取組件里的sprite
   SpriteRenderer.sprite=sprites[frame];
  }
 }