https://learn.microsoft.com/en-us/windows-hardware/drivers/ddi/d3d10umddi/nc-d3d10umddi-pfnd3d11ddi_copystructurecount
PFND3D11DDI_COPYSTRUCTURECOUNT (d3d10umddi.h) - Windows drivers | Microsoft Learn
The CopyStructureCount function copies the number of items in the filled portion (that is, the filled-size value) of an append buffer unordered access view...
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