let x, y;

let x2, y2;

let x3, y3;

​

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

let xspeed = 1;

let yspeed = 1.2;

​

let x2speed = 2;

let y2speed = 2.8;

​

let x3speed = 3;

let y3speed = 3.5;

​

function setup() {

  createCanvas(400, 400);

  // Initialize the position in the center

  x = width / 2;

  y = height / 2;

​

  x2 = width / 2;

  y2 = height / 2;

​

  x3 = width / 2;

  y3 = height / 2;

}

​

function draw() {

  background(220);

​

  // Move the ball ball, either right or left

  x += xspeed;

  y += yspeed;

​

  x2 += x2speed;

  y2 += y2speed;

​

  x3 += x3speed;

  y3 += y3speed;

​

  // Simplified Version:

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

  if (x <= 0 || x >= width) {

    // Flip the sign of the direction

    xspeed *= -1;

  }

​

  if (y <= 0 || y >= height) {

    // Flip the sign of the direction

    yspeed *= -1;

  }

​

  if (x2 <= 0 || x2 >= width) {

    // Flip the sign of the direction

    x2speed *= -1;

  }

​

  if (y2 <= 0 || y2 >= height) {

    // Flip the sign of the direction

    y2speed *= -1;

  }

  if (x3 <= 0 || x3 >= width) {

    // Flip the sign of the direction

    x3speed *= -1;

  }

​

  if (y3 <= 0 || y3 >= height) {

    // Flip the sign of the direction

    y3speed *= -1;

  }

​

  // Draw the ball

  ellipse(x, y, 50, 50);

  ellipse(x2, y2, 30, 30);

  ellipse(x3, y3, 20, 20);

}

​