C++ RWStructuredBuffer计数器不递减（DX12）

我正在尝试使用DX12在DXR中实现光子映射。撇开细节不谈，我有一个存储光子的结构化缓冲区。缓冲区从最近的命中着色器中写入，我通过计数器从多个线程组同步写入该缓冲区。这是可行的，我的光子被愉快地存储了起来。然后，我为这个缓冲区内的所有光子调用一个实例绘制，这将光栅化它们在屏幕上的飞溅半径。理论上，我应该能够减少这个绘制的顶点着色器中的计数器，并使其返回到0。但是，即使我这样做，计数器也不会重置为0。这意味着，当我每帧移动光源时，光子缓冲区不会更新，因为它从初始帧开始已经满了。任何关于我做错了什么的帮助都会很好。：）

注意-我曾尝试在hlsl中使用InterlockedAdd（countingBufferIndex，1，dstIndex）来同步对缓冲区的访问，而不是调用dstIndex=buffer.IncrementCounter（），但是在这种情况下，只有少量光子被推送到缓冲区-查看Pix或NSight中的内存，只有大约百分之一的缓冲区被填满

//create the counting buffer for the photons
void Application::CreateCountBuffer() {
    auto device = m_deviceResources->GetD3DDevice();

    UINT size = 4;
    D3D12_RESOURCE_DESC desc = {};
    desc.Alignment = 0;
    desc.DepthOrArraySize = 1;
    desc.Dimension = D3D12_RESOURCE_DIMENSION_BUFFER;
    desc.Flags = D3D12_RESOURCE_FLAG_ALLOW_UNORDERED_ACCESS;
    desc.Format = DXGI_FORMAT_UNKNOWN;
    desc.Height = 1;
    desc.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
    desc.MipLevels = 1;
    desc.SampleDesc.Count = 1;
    desc.SampleDesc.Quality = 0;
    desc.Width = (UINT64)size;
    auto heapProps = CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_DEFAULT);

    ThrowIfFailed(device->CreateCommittedResource(&heapProps, D3D12_HEAP_FLAG_NONE, &desc,  D3D12_RESOURCE_STATE_UNORDERED_ACCESS, nullptr, IID_PPV_ARGS(&photonCountBuffer)));

    photonCountBuffer->SetName(L"CountingPhotonsBuffer");
    photonCounterDescriptorHeapIndex = AllocateDescriptor(&photonCountCPUDescriptor, photonCounterDescriptorHeapIndex);

    D3D12_UNORDERED_ACCESS_VIEW_DESC uavDesc = {};
    uavDesc.ViewDimension = D3D12_UAV_DIMENSION_BUFFER;
    uavDesc.Format = DXGI_FORMAT_R32_TYPELESS;
    uavDesc.Buffer.NumElements = 1;
    uavDesc.Buffer.Flags = D3D12_BUFFER_UAV_FLAG_RAW;

    device->CreateUnorderedAccessView(photonCountBuffer.Get(), nullptr, &uavDesc, photonCountCPUDescriptor);
    photonCounterGpuDescriptor = CD3DX12_GPU_DESCRIPTOR_HANDLE(m_descriptorHeap->GetGPUDescriptorHandleForHeapStart(), photonCountUavDescriptorHeapIndex, m_descriptorSize);
}

///////////光线跟踪着色器中光子结构化缓冲区和计数器缓冲区的寄存器/////////////
RWStructuredBuffer photonBuffer：寄存器（u1）；
rwByteAddressBufferPhotonBufferCounter：寄存器（u2）；
////////////存储光子-在最近的命中着色器中调用/////////////////
uint dstIndex=photonBuffer.IncrementCounter（）；
float raySize=sqrt（点（pos-WorldRayOrigin（），pos-WorldRayOrigin（））；
光子p={float4（pos，raySize），float4（dir，1），float4（color，1），float4（attr.normal，1）}；
如果（dstIndex<光子计数）{
photonBuffer[dstIndex]=p；
}
否则{
uint decre=photonBuffer.DecrementCounter（）；
}
}

/////////////光栅管道中光子缓冲区的寄存器//////////////////////////////////////////////////////////////////////
RWStructuredBuffer光子：寄存器（u1）；
//////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////
///////////减量计数器-在实例化绘制的顶点着色器内调用（称为每光子）//////
/////////////////////////////////////////////////////////////////////////////////////////////////////
PSInput VSMain（浮点4位置：位置，uint实例ID:SV_实例ID，浮点4颜色：颜色）
{
浮动lMax=50；
浮点数MaxMajorkernerRadius=10；
float minMajKernelRadius=0.1；
浮点数pi=3.141592653589793238462642283279502841971F；
输入结果；
光子=光子[实例ID]；
uint decre=光子。DecrementCounter（）；
.
.
.
}

//create the RWStructuredBuffer for storing the photons
void Application::CreatePhotonStructuredBuffer() {
    
    auto device = m_deviceResources->GetD3DDevice();
    auto backBufferFormat = m_deviceResources->GetBackBufferFormat();
    {
        UINT64 size = sizeof(Photon);
        UINT64 bufferSize = PHOTON_COUNT * size;
        auto uavDesc = CD3DX12_RESOURCE_DESC::Buffer(bufferSize, D3D12_RESOURCE_FLAG_ALLOW_UNORDERED_ACCESS);
        auto defaultHeapProperties = CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_DEFAULT);

        ThrowIfFailed(device->CreateCommittedResource(&defaultHeapProperties, D3D12_HEAP_FLAG_NONE, &uavDesc, D3D12_RESOURCE_STATE_UNORDERED_ACCESS, nullptr, IID_PPV_ARGS(&photonStructBuffer)));
        NAME_D3D12_OBJECT(photonStructBuffer);

        photonStructGpuHeapIndex = AllocateDescriptor(&photonStructCPUDescriptor, photonStructGpuHeapIndex);
        D3D12_UNORDERED_ACCESS_VIEW_DESC uavPhotonDesc = {};
        uavPhotonDesc.Buffer.NumElements = PHOTON_COUNT;
        uavPhotonDesc.Buffer.FirstElement = 0;
        uavPhotonDesc.Buffer.StructureByteStride = size;
        uavPhotonDesc.Buffer.CounterOffsetInBytes = 0;
        uavPhotonDesc.Format = DXGI_FORMAT_UNKNOWN;
        uavPhotonDesc.ViewDimension = D3D12_UAV_DIMENSION_BUFFER;
        device->CreateUnorderedAccessView(photonStructBuffer.Get(),photonCountBuffer.Get(), &uavPhotonDesc, photonStructCPUDescriptor);
        photonStructGPUDescriptor = CD3DX12_GPU_DESCRIPTOR_HANDLE(m_descriptorHeap->GetGPUDescriptorHandleForHeapStart(), photonStructGpuHeapIndex, m_descriptorSize);
    }
}

///////////Registers for Photon Structured Buffer and counter buffer within Ray-Tracing shader/////////////
RWStructuredBuffer<Photon> photonBuffer : register(u1);
RWByteAddressBuffer photonBufferCounter : register(u2);
////////////Storing Photons - called within a Closest Hit shader/////////////////


        uint dstIndex = photonBuffer.IncrementCounter();
        float raySize = sqrt(dot(pos - WorldRayOrigin(), pos - WorldRayOrigin()));
        Photon p = { float4(pos, raySize), float4(dir, 1), float4(colour, 1), float4(attr.normal, 1) };
        
        if (dstIndex < PHOTON_COUNT) {
            photonBuffer[dstIndex] = p;
        }
        else {
           uint decr = photonBuffer.DecrementCounter();
            }
        }
        

/////////////Register for Photon Buffer within Raster Pipeline //////////////////////////////////////////////////////////////////////
RWStructuredBuffer<Photon> photons : register(u1);
//////////////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////////////////////
///////////Decrement Counter - called within the vertex shader of an instanced draw (called per photon)//////
/////////////////////////////////////////////////////////////////////////////////////////////////////

PSInput VSMain(float4 position : POSITION, uint instanceID : SV_InstanceID, float4 color : COLOR)
{
    float lMax = 50;
    float maxMajorKernelRadius = 10;
    float minMajKernelRadius = 0.1;
    float pi = 3.1415926535897932384626422832795028841971f;

    PSInput result;
    Photon photon = photons[instanceID];
    uint decr = photons.DecrementCounter();
    .
    .
    .
    }