在DirectX 11中更改分辨率

Question

如何更改DirectX 11中的屏幕分辨率？有沒有一個簡單的方法來做到這一點，或者我必須完全重新創建交換鏈，並創建一個新的backbuffer和rendertargetview？

Answer 1

DXGI自動處理調整「前端緩衝區」的大小，即顯示給用戶的交換鏈部分。但是，應用程序負責調整「後臺緩衝區」的大小。當你這樣做時，你還應該重新創建所有'依賴於窗口大小'的資源。

的基本邏輯很簡單：

// 1. Clear the existing references to the backbuffer 
ID3D11RenderTargetView* nullViews [] = { nullptr }; 
m_d3dContext->OMSetRenderTargets(ARRAYSIZE(nullViews), nullViews, nullptr); 
m_renderTargetView.Reset(); // Microsoft::WRL::ComPtr here does a Release(); 
m_depthStencilView.Reset(); 
m_d3dContext->Flush(); 

// 2. Resize the existing swapchain 
hr = m_swapChain->ResizeBuffers(2, backBufferWidth, backBufferHeight, backBufferFormat, 0); 
if (hr == DXGI_ERROR_DEVICE_REMOVED || hr == DXGI_ERROR_DEVICE_RESET) 
    // You have to destroy the device, swapchain, and all resources and 
    // recreate them to recover from this case. The device was hardware reset, 
    // physically removed, or the driver was updated and/or restarted 

之後，步驟，其餘都是你做了什麼，當你第一次創建swapchain

// 3. Get the new backbuffer texture to use as a render target 
hr = m_swapChain->GetBuffer(0, __uuidof(ID3D11Texture2D), &backBuffer); 

hr = m_d3dDevice->CreateRenderTargetView(backBuffer.Get(), nullptr, &m_renderTargetView); 

// 4. Create a depth/stencil buffer and create the depth stencil view 
CD3D11_TEXTURE2D_DESC depthStencilDesc(depthBufferFormat, backBufferWidth, backBufferHeight, 1, 1, D3D11_BIND_DEPTH_STENCIL); 
hr = m_d3dDevice->CreateTexture2D(&depthStencilDesc, nullptr, &depthStencil); 

CD3D11_DEPTH_STENCIL_VIEW_DESC depthStencilViewDesc(D3D11_DSV_DIMENSION_TEXTURE2D); 
hr = m_d3dDevice->CreateDepthStencilView(depthStencil.Get(), &depthStencilViewDesc, &m_depthStencilView)); 

// 5. Reset the rendering viewport to the new size 
CD3D11_VIEWPORT viewPort(0.0f, 0.0f, static_cast<float>(backBufferWidth), static_cast<float>(backBufferHeight)); 
m_d3dContext->RSSetViewports(1, &viewPort); 

// 6. Reset your camera's aspect ratio based on backBufferWidth/backBufferHeight 

// 7. Set your render target view/depth stencil view for rendering 
m_d3dContext->OMSetRenderTargets(1, m_renderTargetView.GetAddressOf(), m_depthStencilView.Get()); 

對於Win32桌面應用程序中，絕招正好知道要做這個過程。

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) 
{ 
    PAINTSTRUCT ps; 
    HDC hdc; 

    static bool s_in_sizemove = false; 
    static bool s_minimized = false; 

    switch (message) 
    { 

    ... 

    case WM_SIZE: 
     if (wParam == SIZE_MINIMIZED) 
     { 
      if (!s_minimized) 
      { 
       s_minimized = true; 
       // Your app should probably suspend 
      } 
     } 
     else if (s_minimized) 
     { 
      s_minimized = false; 
      // Your app should resume 
     } 
     else if (!s_in_sizemove) 
      // HERE is where you'd trigger a resize based on MINIMIZE/MAXIMIZE/RESTORE 
     break; 

    case WM_ENTERSIZEMOVE: 
     s_in_sizemove = true; 
     break; 

    case WM_EXITSIZEMOVE: 
     s_in_sizemove = false; 
     // HERE is where you'd trigger a resize based on the user resizing the window 
     break; 

     case WM_GETMINMAXINFO: 
     { 
      // You should set a minimize window size that is reasonable for your app. Here I use 320x200 
      auto info = reinterpret_cast<MINMAXINFO*>(lParam); 
      info->ptMinTrackSize.x = 320; 
      info->ptMinTrackSize.y = 200; 
     } 
     break; 
    } 

    ... 
    return DefWindowProc(hWnd, message, wParam, lParam); 
} 

對於Windows Store應用程序/ Windows的手機應用程序，該VS模板有用於創建設備，另一個用於創建設備相關的資源，獨特的功能，另一個用於創建窗口大小依賴的資源。最後一個被調用來調整大小。

全屏模式有點棘手，但基本上是一樣的想法。如果您的應用程序不支持全屏，你應該確保禁用默認ALT +通過調用這個ENTER行爲，當你第一次創建swapchain和設置HWND協會：

dxgiFactory->MakeWindowAssociation(hWnd, DXGI_MWA_NO_ALT_ENTER); 

的Windows Store應用程序/ Windows手機應用程序不允許真正的「全屏」模式分辨率更改，因此這種情況不適用於它們。

見DirectX Graphics Infrastructure (DXGI): Best Practices