This is not the rudimentary turtle-graphics system I wrote as a teenager

[mmcirvin]

This is only the tribute.

I was fascinated by turtle graphics, as embodied in the computer language LOGO, which was intended for kids. This is a system where your drawing cursor, the "turtle", has a position and a movement direction associated with it, and takes relative angular rotation and forward movement instructions. It's good for drawing things like simple fractals and certain mathematical curves.

The first thing I implemented, I recall, was an interactive turtle graphics system where the user chose commands directly from a menu by number. But that was pretty limited for anything other than simple geometric doodling. What I really wanted was a turtle-graphics library I could call from BASIC. Well, in a language that doesn't even really have functions that is a kind of awkward thing to manage, but I did figure out that I could have a kind of named GOSUB by assigning a line number to a variable, so that was nice. I just had to put all my "arguments" in special global variables and then call GOSUB TURN or GOSUB DRAW, etc. Then I had a sort of BASIC program skeleton I could save on a floppy, load whenever I wanted and put my little application at the beginning. It was sort of a mess, but it worked. It's long-gone, but today I reconstructed something like it in a couple of hours.