什么时候在 RTV/DSV 上调用 DiscardView？

Question

在清除关联视图之前立即调用 DiscardView 是否安全？似乎滥用此 API 可能会导致不好的事情，因此非常感谢有关如何有效使用它的一些解释。

Answer 1

DiscardView是对分块硬件渲染的优化，所以不是严格要求。

在标准 Windows 8 Store、Windows phone 8 和通用 Windows 应用程序模板中，它在 Present[=13 之后调用=]

void DX::DeviceResources::Present() 
{
    // The first argument instructs DXGI to block until VSync, putting the application
    // to sleep until the next VSync. This ensures we don't waste any cycles rendering
    // frames that will never be displayed to the screen.
    HRESULT hr = m_swapChain->Present(1, 0);

    // Discard the contents of the render target.
    // This is a valid operation only when the existing contents will be entirely
    // overwritten. If dirty or scroll rects are used, this call should be removed.
    m_d3dContext->DiscardView(m_d3dRenderTargetView.Get());

    // Discard the contents of the depth stencil.
    m_d3dContext->DiscardView(m_d3dDepthStencilView.Get());

    // If the device was removed either by a disconnection or a driver upgrade, we 
    // must recreate all device resources.
    if (hr == DXGI_ERROR_DEVICE_REMOVED || hr == DXGI_ERROR_DEVICE_RESET)
    {
        HandleDeviceLost();
    }
    else
    {
        DX::ThrowIfFailed(hr);
    }
}

什么时候在 RTV/DSV 上调用 DiscardView？

When to call DiscardView on RTV/DSV?

direct3d11