ComputeShader中Counter類型的使用

接上一篇:http://www.javashuo.com/article/p-ccyhllxl-ed.html

 

除了Append類型對應的Consume/AppendStructuredBuffer還有一個Counter類型能夠進行計數操做。

 

那麼測試一下:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class ComputeShaderTest : MonoBehaviour
{
    public ComputeShader computeShader;


    void Awake()
    {
        var kernelID = computeShader.FindKernel("CSMain");
        var counterBuffer = new ComputeBuffer(1, sizeof(int), ComputeBufferType.Counter);
        counterBuffer.SetCounterValue(5);

        computeShader.SetBuffer(kernelID, "counter", counterBuffer);
        computeShader.Dispatch(kernelID, 1, 1, 1);

        var argBuffer = new ComputeBuffer(1, sizeof(int), ComputeBufferType.IndirectArguments);
        ComputeBuffer.CopyCount(counterBuffer, argBuffer, 0);
        //經過這個方法拿到第一個數據。

        int[] counter = new int[1] { 0 };
        argBuffer.GetData(counter);

        int count = counter[0];

        Debug.Log("count: " + count);

        argBuffer.Release();
        counterBuffer.Dispose();
    }
}

 

computer shader:

#pragma kernel CSMain

RWStructuredBuffer<int> counter;

[numthreads(8, 1, 1)]
void CSMain(uint3 id : SV_DispatchThreadID)
{
    if (id.x == 1 || id.x == 2 || id.x == 3)
    {
        //counter.IncrementCounter();
        counter.DecrementCounter();
    }
}

 

測試的是DecrementCounter最終打印2。

 

 

另外須要注意，若是在同一個csmain裏同時進行加減操做則會報錯：

RWStructuredBuffers may increment or decrement their counters, but not both. at kernel CSMain