On Fri, Jul 15, 2016 at 6:47 PM, Paul Koning <paulkon...@comcast.net> wrote: > I remember, around the same time, the Tektronix 4010. But that was > far less flexible; it could only draw, not erase, unlike the PLATO terminals.
The 4010 can erase just fine. The problem is that it can't do selective erase, only full-screen erase, and erasing is a slow operation. Tektronix had other models that could do both storage and refresh graphics, but they were even more expensive. The refresh capabilities tended to be fairly limited.
