title: Raster Operator to use for MaskBlt
body: <p>I'm trying to use the GDI MaskBlt command to draw an image with transparency: <a href="http://msdn.microsoft.com/en-us/library/dd145047(VS.85).aspx" rel="nofollow noreferrer">http://msdn.microsoft.com/en-us/library/dd145047(VS.85).aspx</a></p>
  
  <p>I can't seem to find anything in the documentation about what raster operator to use for the obvious use case: a sort of <code>MAKEROP4(SRCCOPY, DSTCOPY)</code> - blitting where the mask is 1, and leaving the destination untouched where the mask is 0. SRCCOPY is a valid ROP, but what should I use in place of my fictional <code>DSTCOPY</code> ?</p>