title: What User Mode Graphics Driver (UMD) does OpenGL call in the Graphics Pipeline?
body: <p>According to <a href="http://msdn.microsoft.com/en-us/library/windows/hardware/ff570114%28v=vs.85%29.aspx" rel="nofollow">Windows</a>:</p>
  
  <blockquote>
    <p>Graphics hardware vendors must write user-mode display drivers for
    their display adapters. The user-mode display driver is a dynamic-link
    library (DLL) that is loaded by the Microsoft Direct3D runtime. A user-mode display driver must at least support the Direct3D version 9 DDI.</p>
  </blockquote>
  
  <p>e.g. <strong>nvd3dum.dll</strong> is the UMD for DirectX11 running with Nvidia. So shader compilation happens here from DirectX code called from the API, before it goes to the Kernal Mode Driver. </p>
  
  <hr>
  
  <p>Also does a UMD put code in a intermediate representation? (e.g. can you say the driver is a Intermediate Language)?</p>