如何在C++ Win32D2D中初始化Direct2D环境？

在C++中使用Win32D2D（Windows Direct2D）初始化Direct2D环境通常涉及以下步骤[^1]：

1. **包含头文件**:

   #include <d2d1.h>
   #include <dxgi1_2.h>

2. **创建DXGIFactory接口**:

   Microsoft::WRL::ComPtr<IDXGIFactory2> dxgiFactory;
   HRESULT hr = CreateDXGIFactory2(__uuidof(IDXGIFactory2), reinterpret_cast<void**>(&dxgiFactory));

3. **获取设备和交换链**:

   Microsoft::WRL::ComPtr<IDXGISwapChain1> swapChain;
   hr = dxgiFactory->CreateSwapChainForHwnd(
       nullptr, // window handle
       nullptr, // DXGI_SWAP_CHAIN_DESC (default)
       nullptr, // IUnknown* (default)
       D3D11_CREATE_DEVICE_SINGLETHREADED,
       nullptr, // const D3D_FEATURE_LEVEL*
       &swapChain);

4. **获取D2DDevice**:

   Microsoft::WRL::ComPtr<ID2D1Device> d2dDevice;
   hr = swapChain.As<IDXGISwapChain>()->GetDevice(&d2dDevice);

5. **创建渲染上下文**:

   Microsoft::WRL::ComPtr<ID2D1DeviceContext> d2dContext;
   hr = d2dDevice->CreateDeviceContext(D2D1_DRAWING_STATE_DESCRIPTION{}, &d2dContext);

完成这些步骤后，你就成功地初始化了一个Direct2D环境，可以开始进行绘图操作了。