In my last post , we played The Chaos Game and ended up with a Sierpinski Triangle. It’s quite nice as far as it goes, but there is not a lot of variation and visual interest beyond the initial surpise of finding it buried in the chaos at all. This time around, lets look at the de Jong attractor. First, some terminology! An Attractor is a dynamic system with a set of numeric values to which the system tends to evolve over time, no matter what state it starts in.

Today, we’ll play The Chaos Game! It’s easy to play, and it goes like this: First, put three points on your paper. These will be the vertices of a triangle (so don’t put them in a straight line!) Any triangle will work, but be sure to leave lots of area inside where the triangle will be to make it easier to see what it going on. Next, you need a way to randomly choose one of those vertices over and over.

Let’s draw some squares! Last week I introduced Clojure as a possible replacement for Javascript for my generative art pursuits. Clojure has the Quil library that provides many of the same capabilities that p5.js provides to Javascript. Let’s look at a simple example. This Javascript/p5.js program generates an image like the one at the top of this post. function setup() { createCanvas(800, 800); background(240); stroke(0); let size = 500; let offset = 50; let centerX = width/2; let centerY = height/2; let topLeftX = centerX - size/2; let topLeftY = centerY - size/2; fill(200, 150, 250, 150); rect(topLeftX, topLeftY, size, size); rect(topLeftX-offset, topLeftY-offset, size, size); rect(topLeftX+offset, topLeftY+offset, size, size); } The program is fairly simple: create the canvas, fill in the background with grey, set the stroke (line) color to black, set the fill color, and draw three rectangles slightly offset from each other.

If you’ve been reading my posts each week, you’re probably aware that I have been working mostly in Javascript, using the p5.js drawing library. There are many things to like about Javascript, but also many ways for it to slowly drive you bonkers. I won’t go into all those reasons here, but I will say it’s time to try something new. I’d like to try to do some generative art using the Clojure language.