https://learn.microsoft.com/en-us/windows/win32/api/d3d11/nf-d3d11-id3d11asynchronous-getdatasize
ID3D11Asynchronous::GetDataSize (d3d11.h) - Win32 apps | Microsoft Learn
Get the size of the data (in bytes) that is output when calling ID3D11DeviceContext::GetData.
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