var y = 180;

var xspeed = 9;

var yspeed = 10;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

  background(25);

}

function draw() {

  background(0);

​

  //distance from center of the screen

  var d = 20;//dist(windowWidth / 2, windowHeight / 2, mouseX, mouseY);

​

  //fill(random(200, 250), random(200, 250), random(200, 250));

  ellipse(x, y, d, d);

​

  //bouncing horizontally

  x = x + xspeed;

​

  if (x > windowWidth || x < 0) {

    xspeed = -xspeed;

  }

​

  //bouncing veritcally

  y = y + yspeed;

​

  if (y > windowHeight || y < 0) {

    yspeed = -yspeed;

  }

}

​