text: /*
  https://vimeo.com/channels/learningp5js/139587733
  */
  
  var ball = {
    x: 300,
    y: 200,
    xspeed: 4,
    yspeed: -3
  };
  
  function setup() {
    createCanvas(600, 400);
  }
  
  function draw() {
    background(0);
    stroke(255);
    strokeWeight(4);
    noFill();
    ellipse(ball.x, ball.y, 24, 24);
  
    if (ball.x > width || ball.x < 0) {
      ball.xspeed = ball.xspeed * -1;
    }
  
    if (ball.y > height || ball.y < 0) {
      ball.yspeed = ball.yspeed * -1;
    }
  
    ball.x = ball.x + ball.xspeed;
    ball.y = ball.y + ball.yspeed;
  }
  