This has to be one of the first “CAD Demonstrations” in history, and it is pretty amazing what could be done with 1963 computer technology (actually the rig they are on was built in 1958, predating the microchip).  From the description, this video depicts:

…the software Ivan Sutherland developed in his 1963 thesis at MIT’s Lincoln Labs, “Sketchpad, A Man-Machine Graphical Communication System”, described as one of the most influential computer programs ever written. This work was seminal in Human-Computer Interaction, Graphics and Graphical User Interfaces (GUIs), Computer Aided Design (CAD), and constraint/object-oriented programming.

Here are both parts:

Click here to view the embedded video.

Click here to view the embedded video.

They cover all of the basics for 3D computer modeling.  They have sketching, snapping, constraining, modifying, importing, and view manipulation down just as well as any modern CAD software (minus some of what amounts to special effects).  In fact, the stylus interface used is only recently coming back into style.  And there is some discussion about other human-computer interfaces they were developing at the time that we still haven’t quite figured out, like speech and handwriting recognition.  I guess hard problems are hard.

It’s particularly interesting to me the blend of parametric and direct modeling, being able to apply rigid constraints on the one hand and deforming the model dynamically on the other.  It seems like MIT Lincoln Labs had CAD all figured out a half century ago, and the rest has all been largely cosmetic.  You can even find Ivan Sutherland’s entire thesis on Sketchpad online here.  In it he details everything from constructing the “light-pen” to the different constraint solving methods available.

I especially like the first demonstrator’s objection handling.  Like in the second video (5:45) when asked about drawing non-linear models, such as an automobile, and he simply replies, “we are well on our way with surfaces.”  Brilliant.  I think I’ve used that exact line a dozen times, 46 years later.

I think it’s especially important to note how much enjoyment everyone seems to get out of this little experiment.  The guys on stage are smiling, the audience laughs as they play along, and now hundreds of thousands of folks are watching online.  People like things they are familiar with, and it is striking when something they have never actually experienced before hits that familiarity chord anyways.  There is an intrinsic attraction to consonance, and maybe some muster behind the notion that music is a universal language.