Yay! Bill Atkinson’s source code for the original MacPaint (and QuickDraw) has finally been released to the public in the form of a donation to the Computer Museum in Mountain View.
http://www.computerhistory.org/highlights/macpaint/
In writing MacPaint, Bill was as concerned with whether human readers would understand the code as he was with what the computer would do with it. He later said about software in general, “It’s an art form, like any other art form… I would spend time rewriting whole sections of code to make them more cleanly organized, more clear. I’m a firm believer that the best way to prevent bugs is to make it so that you can read through the code and understand exactly what it’s doing… And maybe that was a little bit counter to what I ran into when I first came to Apple… If you want to get it smooth, you’ve got to rewrite it from scratch at least five times.”
Now mere mortals like myself can study the magic.