DirectX 11 framebuffer capture (C++, no Win32 or D3DX)

Question

I would like to capture the contents of my front or back buffer using DirectX 11 into an array of bytes which I can then use as a texture or as a source for creating a file.

Answer 1

So. A little more experimentation revealed the "problem". By getting the description of the framebuffer texture and using that as the basis to create the new texture the problem was resolved...

ID3D11Texture2D* pSurface;
HRESULT hr = m_swapChain->GetBuffer( 0, __uuidof( ID3D11Texture2D ), reinterpret_cast< void** >( &pSurface ) );
if( pSurface )
{
    const int width = static_cast(m_window->Bounds.Width * m_dpi / 96.0f);
    const int height = static_cast(m_window->Bounds.Height * m_dpi / 96.0f);
    unsigned int size = width * height;
    if( m_captureData )
    {
        freeFramebufferData( m_captureData );
    }
    m_captureData = new unsigned char[ width * height * 4 ];

    ID3D11Texture2D* pNewTexture = NULL;

    D3D11_TEXTURE2D_DESC description;
    pSurface->GetDesc( &description );
    description.BindFlags = 0;
    description.CPUAccessFlags = D3D11_CPU_ACCESS_READ | D3D11_CPU_ACCESS_WRITE;
    description.Usage = D3D11_USAGE_STAGING;

    HRESULT hr = m_d3dDevice->CreateTexture2D( &description, NULL, &pNewTexture );
    if( pNewTexture )
    {
        m_d3dContext->CopyResource( pNewTexture, pSurface );
        D3D11_MAPPED_SUBRESOURCE resource;
        unsigned int subresource = D3D11CalcSubresource( 0, 0, 0 );
        HRESULT hr = m_d3dContext->Map( pNewTexture, subresource, D3D11_MAP_READ_WRITE, 0, &resource );
        //resource.pData; // TEXTURE DATA IS HERE

        const int pitch = width << 2;
        const unsigned char* source = static_cast< const unsigned char* >( resource.pData );
        unsigned char* dest = m_captureData;
        for( int i = 0; i < height; ++i )
        {
            memcpy( dest, source, width * 4 );
            source += pitch;
            dest += pitch;
        }

        m_captureSize = size;
        m_captureWidth = width;
        m_captureHeight = height;

        return;
    }

    freeFramebufferData( m_captureData );
}