let x,y

​

// Declare a variable for the horizontal speed of the ball

let xspeed = 1;

let yspeed = 2;

​

function setup() {

  createCanvas(600, 500);

  // Initialize the position in the center

  x = width / 2;

  y= height /2;  

}

​

function draw() {

  background(220);

  move();

  bounce();

  bounce();

  display();

  // Move the ball ball, either right or left

  function move(){

   x += xspeed;

   y += yspeed; 

  }

​

  function bounce(){

  // Simplified Version:

  // When the ball is at either left or right border

   if (x < 0 || x > width) {

    xspeed *= -1;

  }

}

​

function display(){

  // Draw the ball

  ellipse(x, y, 50, 50);

}

}