Chapter 4. The Wrong Way to Draw a Circle


To most, trigonometry is a scary word. I’ll be the first to confess that it utterly bewildered me at school. I remember thinking to myself that I would never use this crap in the real world. And I was right—for a couple of years at least.

Until sometime in my late twenties, I found myself making Flash games for a living, and more and more I found bits of half-remembered trig proving useful.

In this chapter, we’ll play with unconventional ways of drawing circles, for which we’ll need a little trig. In the same way we wandered away from the useful convenience of the line function in the last chapter, we won’t rely on Processing’s ellipse function here. Instead, by working out the math ourselves, we’ll be able to tease out a more nonmechanical, imprecise way of drawing this one shape. Many of my own works have been based on this single idea—rotational drawing algorithms—and so I’ll offer one of them as a case study later in the chapter.

4.1. Rotational drawing

4.2. Case study: Wave Clock

4.3. Summary