如何创建暂存ID3D11Texture2D纹理？

Question

我使用以下代码创建了一个交换链：

DXGI_SWAP_CHAIN_DESC swapchainDesc;

// Clear out the struct for use
ZeroMemory(&swapchainDesc, sizeof(DXGI_SWAP_CHAIN_DESC));

// Fill the swap chain description struct
swapchainDesc.BufferCount = 1;                                    // one back buffer
swapchainDesc.BufferDesc.Width = width;
swapchainDesc.BufferDesc.Height = height;
swapchainDesc.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;     // use 32-bit color DXGI_FORMAT_R8G8B8A8_UNORM DXGI_FORMAT_R32G32B32_FLOAT
swapchainDesc.BufferDesc.RefreshRate.Numerator = 60;
swapchainDesc.BufferDesc.RefreshRate.Denominator = 1;
swapchainDesc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;      // how swap chain is to be used
swapchainDesc.OutputWindow = hWnd;                                // the window to be used
swapchainDesc.SampleDesc.Count = 1;                               // how many multisamples (1-4, above is not guaranteed for DX11 GPUs)
swapchainDesc.SampleDesc.Quality = 0;                             // multisample quality level
swapchainDesc.Windowed = TRUE;                                    // windowed/full-screen mode

// Configure DX feature level
D3D_FEATURE_LEVEL featureLevels[] =
{
    D3D_FEATURE_LEVEL_11_1,
    D3D_FEATURE_LEVEL_11_0,
    D3D_FEATURE_LEVEL_10_1,
    D3D_FEATURE_LEVEL_10_0
};
UINT numFeatureLevels = ARRAYSIZE(featureLevels);

char devname_dx[128];
bool device_ok = getAdapter(&adapter, devname_dx);

DXGI_ADAPTER_DESC adapterDesc;
adapter->GetDesc(&adapterDesc); //devid = 9436, subsysid = 177803304
std::cout << "DirectX GPU " << devname_dx << " : [BusID " << adapterDesc.DeviceId << " | DevID " << adapterDesc.SubSysId << "]" << std::endl;

// Create a device, device context and swap chain using the information in the scd struct
hr = D3D11CreateDeviceAndSwapChain(
    adapter,                    // graphics adapter, which was already checked for CUDA support
    D3D_DRIVER_TYPE_UNKNOWN,    // If adapter is not NULL, we need to use UNKNOWN, otherwise use D3D_DRIVER_TYPE_HARDWARE
    NULL,                       // software
    NULL,                       // flags 
    featureLevels,              // D3D features to enable
    numFeatureLevels,           // D3D feature count
    D3D11_SDK_VERSION,          // D3D SDK version (here 11)
    &swapchainDesc,                     // swap chain description
    &swapchain,                 // swap chain
    &device,                    // D3D device
    NULL,                       // supported feature level (use DXGI_ADAPTER_DESC variable to retrieve the information, e.g. &featureLevel)
    &device_context);           // D3D device context
if (FAILED(hr))
{
    std::string msg = std::string("Failed to create DX device and swap chain: ") + std::to_string(hr);
    throw std::exception(msg.c_str());
}

释放我的适配器后

adapter->Release();

并检索我的设备上下文

device->GetImmediateContext(&device_context);

我映射 2D 纹理

texture_rgb

作为唯一的缓冲区

hr = swapchain->GetBuffer(0, __uuidof(ID3D11Texture2D), (LPVOID*)&texture_rgb);

我的渲染目标视图使用的

hr = device->CreateRenderTargetView(texture_rgb, nullptr, &rtv);

我想创建一个分段 2D 纹理。目前它仅用于查找一些像素数据，但稍后我会将其与 CUDA 集成。它反映了我的

texture_rgb

的内容 - 尺寸、颜色格式、像素数据等。

为了做到这一点，我检索了

texture_rgb

的描述

D3D11_TEXTURE2D_DESC texture_rgb_debugDesc;
texture_rgb->GetDesc(&texture_rgb_debugDesc);

并仅修改

D3D11_TEXTURE2D_DESC::Usage

组件

texture_rgb_debugDesc.Usage = D3D11_USAGE::D3D11_USAGE_STAGING;

然后我尝试使用修改后的描述来创建其他纹理

ID3D11Texture2D* texture_rgb_debug = nullptr;
hr = device->CreateTexture2D(&texture_rgb_debugDesc, nullptr, &texture_rgb_debug);

但是，DirectX 失败并出现以下错误：

E_INVALIDARG 一个或多个参数无效。

如果我将

D3D11_TEXTURE2D_DESC::Usage

更改为初始值（此处为

D3D11_USAGE_DEFAULT

），则可以毫无问题地创建纹理。

Answer 1

从交换链获得的纹理应该具有

D3D11_BIND_RENDER_TARGET

绑定标志，而使用

D3D11_USAGE_STAGING

的纹理不能用作任何渲染阶段的输入或输出，因此与

D3D11_BIND_RENDER_TARGET

标志不兼容。