using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Rendering;
using UnityEngine.UI;

public class yanchi : MonoBehaviour
{
    public RawImage rimage;
    public RenderTexture rt;
    Queue<Texture2D> qlist = new Queue<Texture2D>();
    List<Texture2D> list = new List<Texture2D>();
    // Start is called before the first frame update
    void Start()
    {
        for (int i = 0; i < maxcount; i++)
        {
            list.Add(new Texture2D(rt.width, rt.height, TextureFormat.RGBA32, false));
        }
        StartCoroutine(GetRenederFPS());
    }
    int maxcount = 1;
    int count=0;
    byte[] bts;
    IEnumerator GetRenederFPS()
    {
        yield return new WaitForSeconds(1) ;
        while (true)
        {
            var req = AsyncGPUReadback.Request(rt);
            yield return new WaitUntil(() => req.done);
            if (!req.hasError)
            {

                if (bts == null)
                {
                    bts = new byte[req.layerDataSize];
                }
                req.GetData<byte>().CopyTo(bts);
                list[count].LoadRawTextureData(bts);
                list[count].Apply();
                qlist.Enqueue(list[count]);
                if (qlist.Count >= maxcount)
                {
                    rimage.texture = qlist.Dequeue();
                }
                count++;
                if(count>= list.Count)
                {
                    count = 0;
                }
                //  tex.SetPixels32(req.GetData<Color32>().ToArray());
            }
            else
            {
                Debug.LogError("Error AsyncGPUReadbackRequest.hasError");
            }
        }
    }
    // Update is called once per frame
    void Update()
    {
    }
}