var rad = 100;

var xpos, ypos;



var xspeed = 24;

var yspeed = 12;



var xdirection = 1;

var ydirection = 1;



function setup() {

  createCanvas(windowWidth,

               windowHeight);

  noStroke();

  ellipseMode(RADIUS);



  xpos = width / 2;

  ypos = height / 2;

}



function draw() {

  background(234,234,234);

   fill(150,25,150);

  xpos = xpos + xspeed * xdirection;

  ypos = ypos + yspeed * ydirection;



  if (xpos > width - rad || xpos < rad) {

    xdirection *= -1;

  }



  if (ypos > height - rad|| ypos < rad) {

  ydirection *= -1;

  }

  ellipse(xpos, mouseY, rad, rad);

  ellipse(mouseX, ypos, rad, rad);

  }