var secondmaxDiameter;

var thirdmaxDiameter;

var fourthmaxDiameter;

var fifthmaxDiameter;

var sixthmaxDiameter;

var seventhmaxDiameter;

var eightmaxDiameter;

var theta; 

​

function setup() {

  createCanvas(900, 500);

​

  maxDiameter = 1000; 

  secondmaxDiameter = 700;

  thirdmaxDiameter = 600;

  fourthmaxDiameter = 300;

  fifthmaxDiameter = 150;

  sixthmaxDiameter = 90;

  seventhmaxDiameter = 50;

  eighthmaxDiameter = 20;

  theta = 0; 

}

​

function draw() {

  background(0); 

​

​

  // calculate the diameter of the circle 

  //height/2 + sin(theta) * amplitude; 

​

  var diam = 100 + sin(theta) * maxDiameter ;

  var seconddiam = 100 + sin(theta) * secondmaxDiameter;

  var thirddiam = 100 + sin(theta) * thirdmaxDiameter;

  var fourthdiam = 100 + sin(theta) * fourthmaxDiameter;

  var fifthdiam = 100 + sin(theta) * fifthmaxDiameter;

  var sixthdiam = 100 + sin(theta) * sixthmaxDiameter;

  var seventhdiam = 100 + sin(theta) * seventhmaxDiameter;

  var eighthdiam = 100 + sin(theta) * eighthmaxDiameter;

  // draw the circles

  stroke(0);

  strokeWeight(0);

  fill(40);

  ellipse(width/2,height/2, diam, diam); 

  fill(35);

  ellipse(width/2,height/2,seconddiam, seconddiam);

  fill(30);

  ellipse(width/2,height/2,thirddiam,thirddiam);

  fill(25);

  ellipse(width/2,height/2,fourthdiam,fourthdiam);

  fill(20);

  ellipse(width/2,height/2,fifthdiam, fifthdiam);

  fill(15);

  ellipse(width/2,height/2,sixthdiam,sixthdiam);

  fill(10);

  ellipse(width/2,height/2,seventhdiam,seventhdiam);

  fill(2);

  ellipse(width/2,height/2,eighthdiam,eighthdiam);

​

  theta += 0.02;

}

​