It is cool and very simple. I created a function named drawCircle() to create a single cluster. A cluster appears on the position of the mouse.
function drawCircle(h, s, b) {
for (var i = 0; i < windowHeight; i += 5) {
rotate(frameCount *0.01);
stroke(h, s, b);
point(i, 0);
}
}
Try it yourself.