gdi32::GdiAlphaBlend

pub unsafe extern "system" fn GdiAlphaBlend(hdcDest: HDC, xoriginDest: c_int, yoriginDest: c_int, wDest: c_int, hDest: c_int, hdcSrc: HDC, xoriginSrc: c_int, yoriginSrc: c_int, wSrc: c_int, hSrc: c_int, ftn: BLENDFUNCTION) -> BOOL