title: Matter.js Collision Not Detecting
body: <p>I'm trying to practice using matter.js to create top down levels Bomberman style.</p>
  
  <p>Right now I want to get my circle, which is controlled by arrow keys to move and bump into static squares but it is just going through them. Did I set it up incorrectly? I have been coding for three months, so I might be quite slow sorry!</p>
  
  <pre><code>var Engine = Matter.Engine,
      World = Matter.World,
      Bodies = Matter.Bodies;
  
  var engine = Engine.create();
  var world = engine.world;
  
  var player;
  var rocks = [];
  var cols = 7;
  var rows = 7;
  
  function setup() {
      createCanvas(750, 750);
      Engine.run(engine);
  
      player = new Player(300, 300, 25);
  
      var spacing = width / cols;
      for (var j = 0; j &lt; rows; j++) {
          for (var i = 0; i &lt; cols; i++) {
              var r = new Rocks(i * spacing, j * spacing);
              rocks.push(r);
          }
      }
  }
  
  function draw() {
      background(51);
      Engine.update(engine);
      for (var i = 0; i &lt; rocks.length; i++) {
          rocks[i].show();
      }
      player.show();
      player.move();
  }
  
  function Player(x, y, r) {
      this.body = Bodies.circle(x, y, r);
      this.r = r;
      World.add(world, this.body);
  
      this.show = function () {
          ellipse(x, y, this.r * 2);
      }
  
      this.move = function () {
          if (keyIsDown(RIGHT_ARROW))
              x += 10;
          if (keyIsDown(LEFT_ARROW))
              x -= 10;
          if (keyIsDown(UP_ARROW))
              y -= 10;
          if (keyIsDown(DOWN_ARROW))
              y += 10;
          x = constrain(x, this.r, height - this.r);
          y = constrain(y, this.r, width - this.r);
      }
  }
  
  function Rocks(x, y, w, h, options) {
      var options = {
          isStatic: true
      }
      this.body = Bodies.rectangle(x, y, h, w, options);
      this.w = w;
      this.h = h;
      this.size = player.r * 2;
      World.add(world, this.body);
  
      this.show = function () {
          rect(x, y, this.size, this.size);
      }
  }
  </code></pre>