On 05/26/2014 02:29 PM, William Donzelli wrote:
  CDC apparently made a "real" graphics
terminal for engineering use,
 because the DD60s and CC545s really were not high performance units
 good for CAD work. 
Absolutely, complete with big-screen long-persistence radar-type tubes.
  But those were an option, not a necessity.  Sometime during the 1970s,
CDC lost interest and the IGS (interactive graphics system) folks moved
on.  But the displays were fun to watch.  Those were actually driven by
a controller with what amounts to a CDC 1700 mini in it.
Sperry also had a 1960s graphics setup.
--Chuck