Sine
/**
* Sine.
*
* Smoothly scaling size with the sin() function.
*/
float diameter;
float angle = 0.0f;
void setup() {
size(640, 360);
diameter = height - 10.0f;
noStroke();
fill(255, 204, 0);
}
void draw() {
background(0);
float d1 = 10.0f + (sin(angle) * diameter/2.0f) + diameter/2.0f;
float d2 = 10.0f + (sin(angle + PI/2.0f) * diameter/2.0f) + diameter/2.0f;
float d3 = 10.0f + (sin(angle + PI) * diameter/2.0f) + diameter/2.0f;
ellipse(0.0f, height/2.0f, d1, d1);
ellipse(width/2.0f, height/2.0f, d2, d2);
ellipse((float)width, height/2.0f, d3, d3);
angle += 0.02f;
}