Daniel Shiffman

   http://natureofcode.com  */

​

var position;

var velocity;

var balls = [];

​

function setup() {

  createCanvas(400, 400);

  fill(255, 174, 0);

  stroke(255, 136, 0);

  position = createVector(100, 100);

  velocity = createVector(2, 4);

  /* Here, we are using a class Vector that contains 

  */

}

​

​

function draw() {

  background(248, 232, 255);

  ellipse(position.x, position.y, 20, 20);

  position.add(velocity);  // why is my ball only moving horizontally?

  if (position.x > 400 || position.x < 0) {

    velocity.x *= -1;

  }

  if (position.y > 400 || position.y < 0) {

    velocity.y *= -1;

  }

  // can you use arrays to generate multiple balls?

}