There are some old threads asking about getting R to display its graphics in an emacs window (e.g. ESS plot directly to an Emacs buffer?) and the ESS manual says,
Of course, the ideal way to use graphics with ESS is to use a windowing system. Under X Windows, or X11, this requires that the DISPLAY environment variable be appropriately set.
But provides no information on how to do so and my google searches only return results similar to the above references. Can someone direct me to a resource to explain how to set up my ess.el file to use emacs as R's DISPLAY environment?