var y = 180;

var r = 25;

var xspeed = 5;

var yspeed = 2;

//

var colorR = 100;

var colorRChange = 5;

​

​

function setup() {

  createCanvas(640, 360);

}

​

function draw() {

  background(colorR,25,85);

 colorR += coloRChange;

  if (x > width - r || x < r) {

    colorRChange = -colorRChange;

  }

  ellipse(x, y, r*2, r*2);

  x += xspeed;

  y += yspeed;

  if (x > width - r || x < r) {

    xspeed = -xspeed;

  }

  if (y > height - r || y < r) {

    yspeed = -yspeed;

  }

}