英伟达的NvAPI如何实现两个D3D11窗口被同一时刻渲染相同的画面，给出详细代码，只有一个设备和上下文，两个窗口

要实现两个D3D11窗口被同一时刻渲染相同的画面，可以使用NvAPI的多GPU API，具体步骤如下：

1. 初始化NvAPI

NvAPI_Status status = NvAPI_Initialize();
if (status != NVAPI_OK)
{
    // 初始化失败
    return;
}

2. 获取设备和上下文句柄

ID3D11Device* pDevice = // 获取设备句柄
ID3D11DeviceContext* pContext = // 获取上下文句柄

3. 创建两个交换链和渲染目标视图

IDXGISwapChain* pSwapChain1;
IDXGISwapChain* pSwapChain2;
ID3D11RenderTargetView* pRTV1;
ID3D11RenderTargetView* pRTV2;

// 创建第一个交换链和渲染目标视图
DXGI_SWAP_CHAIN_DESC desc;
ZeroMemory(&desc, sizeof(desc));
desc.BufferCount = 1;
desc.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
desc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
desc.OutputWindow = hWnd1; // 第一个窗口句柄
desc.SampleDesc.Count = 1;
desc.Windowed = TRUE;

IDXGIDevice* pDXGIDevice;
pDevice->QueryInterface(__uuidof(IDXGIDevice), (void**)&pDXGIDevice);

IDXGIAdapter* pAdapter;
pDXGIDevice->GetAdapter(&pAdapter);

IDXGIFactory* pFactory;
pAdapter->GetParent(__uuidof(IDXGIFactory), (void**)&pFactory);

pFactory->CreateSwapChain(pDevice, &desc, &pSwapChain1);
pFactory->Release();

ID3D11Texture2D* pBackBuffer;
pSwapChain1->GetBuffer(0, __uuidof(ID3D11Texture2D), (LPVOID*)&pBackBuffer);
pDevice->CreateRenderTargetView(pBackBuffer, NULL, &pRTV1);
pBackBuffer->Release();

// 创建第二个交换链和渲染目标视图，与第一个交换链相同
// ...

4. 获取GPU句柄

NvPhysicalGpuHandle gpuHandle;
NvAPI_Status status = NvAPI_D3D11_CreateDevice(pDevice, &gpuHandle);
if (status != NVAPI_OK)
{
    // 获取GPU句柄失败
    return;
}

5. 绑定交换链和渲染目标视图到GPU

NvAPI_Status status1 = NvAPI_D3D11_SetDepthStencil(gpuHandle, pContext);
NvAPI_Status status2 = NvAPI_D3D11_SetViewports(gpuHandle, pContext);
NvAPI_Status status3 = NvAPI_D3D11_SetRenderTargets(gpuHandle, pContext, pRTV1);
NvAPI_Status status4 = NvAPI_D3D11_SetRenderTargets(gpuHandle, pContext, pRTV2);

完整代码如下：

NvAPI_Status status = NvAPI_Initialize();
if (status != NVAPI_OK)
{
    // 初始化失败
    return;
}

ID3D11Device* pDevice = // 获取设备句柄
ID3D11DeviceContext* pContext = // 获取上下文句柄

IDXGISwapChain* pSwapChain1;
IDXGISwapChain* pSwapChain2;
ID3D11RenderTargetView* pRTV1;
ID3D11RenderTargetView* pRTV2;

// 创建第一个交换链和渲染目标视图
DXGI_SWAP_CHAIN_DESC desc;
ZeroMemory(&desc, sizeof(desc));
desc.BufferCount = 1;
desc.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
desc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
desc.OutputWindow = hWnd1; // 第一个窗口句柄
desc.SampleDesc.Count = 1;
desc.Windowed = TRUE;

IDXGIDevice* pDXGIDevice;
pDevice->QueryInterface(__uuidof(IDXGIDevice), (void**)&pDXGIDevice);

IDXGIAdapter* pAdapter;
pDXGIDevice->GetAdapter(&pAdapter);

IDXGIFactory* pFactory;
pAdapter->GetParent(__uuidof(IDXGIFactory), (void**)&pFactory);

pFactory->CreateSwapChain(pDevice, &desc, &pSwapChain1);
pFactory->Release();

ID3D11Texture2D* pBackBuffer;
pSwapChain1->GetBuffer(0, __uuidof(ID3D11Texture2D), (LPVOID*)&pBackBuffer);
pDevice->CreateRenderTargetView(pBackBuffer, NULL, &pRTV1);
pBackBuffer->Release();

// 创建第二个交换链和渲染目标视图，与第一个交换链相同
// ...

NvPhysicalGpuHandle gpuHandle;
NvAPI_Status status = NvAPI_D3D11_CreateDevice(pDevice, &gpuHandle);
if (status != NVAPI_OK)
{
    // 获取GPU句柄失败
    return;
}

NvAPI_Status status1 = NvAPI_D3D11_SetDepthStencil(gpuHandle, pContext);
NvAPI_Status status2 = NvAPI_D3D11_SetViewports(gpuHandle, pContext);
NvAPI_Status status3 = NvAPI_D3D11_SetRenderTargets(gpuHandle, pContext, pRTV1);
NvAPI_Status status4 = NvAPI_D3D11_SetRenderTargets(gpuHandle, pContext, pRTV2);