• http://natureofcode.com/book/chapter-3-oscillation/

cos( counter + offset ) * radius + center

void setup() {

        size(400,400);
        smooth();
        frameRate(30);

}

void draw() {

        background(0);

        float oscOffset = 0.3; // radians
        float oscCounter = 0.11 * frameCount;
        float oscCenter = width/2;
        float oscRadius = width/2;

        float value = cos( oscCounter + oscOffset ) * oscRadius + oscCenter;

        ellipse(value,height*0.333,50,50);

}