Question

            void D3DApp::OnResize()
            {
                assert(md3dImmediateContext);
                assert(md3dDevice);
                assert(mSwapChain);

                // Release the old views, as they hold references to the buffers we
                // will be destroying.  Also release the old depth/stencil buffer.

                ReleaseCOM(mRenderTargetView);
                ReleaseCOM(mDepthStencilView);
                ReleaseCOM(mDepthStencilBuffer);


                // Resize the swap chain and recreate the render target view.

                HR(mSwapChain->ResizeBuffers(1, mClientWidth, mClientHeight, DXGI_FORMAT_R8G8B8A8_UNORM, 0));
                ID3D11Texture2D* backBuffer;
                HR(mSwapChain->GetBuffer(0, __uuidof(ID3D11Texture2D), reinterpret_cast<void**>(&backBuffer)));
                HR(md3dDevice->CreateRenderTargetView(backBuffer, 0, &mRenderTargetView));
                ReleaseCOM(backBuffer);

我在理解这段代码究竟是做什么方面有点麻烦。我认为它是将当前的后台缓冲区存储在内存中，然后再将其渲染到屏幕上？得到的缓冲区内容可能是什么？我很迷茫。我的程序使用800 x 600像素的窗口。

Answer 1

当函数名称指出时，它只是重置backbuffer和rendertarget，每当调整渲染窗口的大小时都应调用此函数。

HR(mSwapChain->ResizeBuffers(1, mClientWidth, mClientHeight, DXGI_FORMAT_R8G8B8A8_UNORM, 0));

在DirectX应用程序中，我们总是将后备缓冲区大小设置为与窗口大小相同，因此当窗口大小发生变化时，我们应该相应地更新后备缓冲区大小，否则您的场景将被拉伸。

ID3D11Texture2D* backBuffer;
HR(mSwapChain->GetBuffer(0, __uuidof(ID3D11Texture2D), reinterpret_cast<void**>(&backBuffer)));
HR(md3dDevice->CreateRenderTargetView(backBuffer, 0, &mRenderTargetView));
ReleaseCOM(backBuffer);

渲染目标基于后备缓冲区，后备缓冲区又应该更新。

C ++中的DirectX Back Buffer代码

1 个答案: