// Daniel Shiffman

// http://natureofcode.com

const { Engine, Bodies, Body, Composite, Vector } = Matter;

​

// A reference to the matter physics engine

let engine;

​

let boundaries = [];

​

let box;

​

function setup() {

  let canvas = createCanvas(640, 240);

​

  // Create the Matter engine

  engine = Engine.create();

​

  // Add a bunch of fixed boundaries

  boundaries.push(new Boundary(width / 2, height - 5, width, 10));

  boundaries.push(new Boundary(width / 2, 5, width, 10));

  boundaries.push(new Boundary(5, height / 2, 10, height));

  boundaries.push(new Boundary(width - 5, height / 2, 10, height));

​

  box = new Box(width / 2, 20, 48, 48);

}

​

function draw() {

  background(255);

​

  // Update the engine!

  Engine.update(engine);

​

  // Display all the boundaries

  for (let i = 0; i < boundaries.length; i++) {

    boundaries[i].show();

  }

​

  box.show();

}

​