DXGI1_3_DDI_BASE_FUNCTIONS.pfnBlt1

Undocumented in source but is binding to Windows. You might be able to learn more by searching the web for its name.
struct DXGI1_3_DDI_BASE_FUNCTIONS
extern (Windows)
HRESULT function(DXGI_DDI_ARG_BLT1*) pfnBlt1;

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