zlacker

>>fs_sof+(OP)
Sutherland figured out how graphic interaction ought to work, with the computer recognizing near points and connecting them. What we now call "snap". He had the key idea of CAD - you can draw with more accuracy if the computer helps.

That demo is running on the MIT TX-0, a transistorized version of Whirlwind and the predecessor of the PDP-1. It was somewhat obsolete at that point, so projects like this could get time on it.

>>Animat+phb
Sutherland started programming on the TX-0, which was widely accessible on the MIT campus, but Sketchpad was definitely done on the big gun, the TX-2, which was still inside Lincoln Laboratories. (Sutherland's uncle-in-law https://en.wikipedia.org/wiki/Ivan_Getting helped get him into Lincoln Labs. See https://www.computerhistory.org/collections/catalog/10273819... .) There's an active TX-2 emulation project at the moment https://tx-2.github.io/ , which has the primary goal of getting Sketchpad running.