DirectX11 C 着色器缓冲区在多边形布局描述上变为null

Question

我正在使用DX11开发游戏引擎。我的问题是我正在受到读取访问违规行为，因为vertexShaderBuffer是nullptr。

bool TerrainShaderClass::InitializeShader(ID3D11Device* device, HWND hwnd, LPCSTR vsFileName, LPCSTR psFileName)
{
    HRESULT result;
    ID3D10Blob* errorMessage = nullptr;
    ID3D10Blob* vertexShaderBuffer = nullptr;
    ID3D10Blob* pixelShaderBuffer = nullptr;
    D3D11_INPUT_ELEMENT_DESC polygonLayout[3];
    unsigned int numElements;
    D3D11_SAMPLER_DESC samplerDesc;
    D3D11_BUFFER_DESC matrixBufferDesc;
    D3D11_BUFFER_DESC lightBufferDesc;

    result = D3DX11CompileFromFile(vsFileName, NULL, NULL, "TerrainVertexShader", "vs_5_0", D3D10_SHADER_ENABLE_STRICTNESS, 0, NULL,
        &vertexShaderBuffer, &errorMessage, NULL);
    if (FAILED(result))
    {
        if (errorMessage)
        {
            OutputShaderErrorMessage(errorMessage, hwnd, vsFileName);
        }
        else
        {
            MessageBox(hwnd, vsFileName, "Missing Shader File", MB_OK);
        }
        return false;
    }
    result = D3DX11CompileFromFile(psFileName, NULL, NULL, "TerrainPixelShader", "ps_5_0", D3D10_SHADER_ENABLE_STRICTNESS, 0, NULL,
        &pixelShaderBuffer, &errorMessage, NULL);
    if (FAILED(result))
    {
        if (errorMessage)
        {
            OutputShaderErrorMessage(errorMessage, hwnd, psFileName);
        }
        else
        {
            MessageBox(hwnd, psFileName, "Missing Shader File", MB_OK);
        }
        return false;
    }
    result = device->CreateVertexShader(vertexShaderBuffer->GetBufferPointer(), vertexShaderBuffer->GetBufferSize(), NULL,
        &m_vertexShader);
    if (FAILED(result))
    {
        return false;
    }
    result = device->CreatePixelShader(pixelShaderBuffer->GetBufferPointer(), pixelShaderBuffer->GetBufferSize(), NULL,
        &m_pixelShader);
    if (FAILED(result))
    {
        return false;
    }
    // This setup needs to match the VertexType stucture in the ModelClass and in the shader.
    polygonLayout[0].SemanticName = "POSITION";
    polygonLayout[0].SemanticIndex = 0;
    polygonLayout[0].Format = DXGI_FORMAT_R32G32B32_FLOAT;
    polygonLayout[0].InputSlot = 0;
    polygonLayout[0].AlignedByteOffset = 0;
    polygonLayout[0].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
    polygonLayout[0].InstanceDataStepRate = 0;
    polygonLayout[1].SemanticName = "TEXCOORD";
    polygonLayout[1].SemanticIndex = 0;
    polygonLayout[1].Format = DXGI_FORMAT_R32G32_FLOAT;
    polygonLayout[1].InputSlot = 0;
    polygonLayout[1].AlignedByteOffset = D3D11_APPEND_ALIGNED_ELEMENT;
    polygonLayout[1].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
    polygonLayout[1].InstanceDataStepRate = 0;
    polygonLayout[2].SemanticName = "NORMAL";
    polygonLayout[2].SemanticIndex = 0;
    polygonLayout[2].Format = DXGI_FORMAT_R32G32B32_FLOAT;
    polygonLayout[2].InputSlot = 0;
    polygonLayout[2].AlignedByteOffset = D3D11_APPEND_ALIGNED_ELEMENT;
    polygonLayout[2].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
    polygonLayout[2].InstanceDataStepRate = 0;
    polygonLayout[3].SemanticName = "COLOR";
    polygonLayout[3].SemanticIndex = 0;
    polygonLayout[3].Format = DXGI_FORMAT_R32G32B32_FLOAT;
    polygonLayout[3].InputSlot = 0;
    polygonLayout[3].AlignedByteOffset = D3D11_APPEND_ALIGNED_ELEMENT;
    polygonLayout[3].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;
    polygonLayout[3].InstanceDataStepRate = 0;
    numElements = sizeof(polygonLayout) / sizeof(polygonLayout[0]);
    result = device->CreateInputLayout(polygonLayout, numElements, vertexShaderBuffer->GetBufferPointer(),
        vertexShaderBuffer->GetBufferSize(), &m_layout);
    if (FAILED(result))
    {
        return false;
    }
    vertexShaderBuffer->Release();
    vertexShaderBuffer = nullptr;
    pixelShaderBuffer->Release();
    pixelShaderBuffer = nullptr;
//Continues

当代码到达polygonLayout[3].InputSlotClass = D3D11_INPUT_PER_VERTEX_DATA;时，缓冲区被设置为正常。但是在该行之后（polygonLayout[3].InstanceDataStepRate = 0;）之后，值不出现原因，

出现了null

result = device->CreateInputLayout(polygonLayout, numElements, vertexShaderBuffer->GetBufferPointer(),
            vertexShaderBuffer->GetBufferSize(), &m_layout);

线抛出例外。

我尝试在线搜索而没有结果。任何帮助深表感谢。预先感谢。

Answer 1

polygonLayout数组仅包含3个项目，因此当您填充polygonLayout[3]时，您会产生缓冲区过度并面对不确定的行为（可能损坏存储在堆栈上的其他变量）。1）让它包含4个项目是一个好主意；2）将Array包装器与（调试）索引检查使用：

::std::array<D3D11_INPUT_ELEMENT_DESC, 4> polygonLayout;