Example.stress2 = function() { var Engine = Matter.Engine, Render = Matter.Render, Runner = Matter.Runner, Body = Matter.Body, Events = Matter.Events, Composite = Matter.Composite, Composites = Matter.Composites, Common = Matter.Common, Constraint = Matter.Constraint, MouseConstraint = Matter.MouseConstraint, Mouse = Matter.Mouse, World = Matter.World, Vertices = Matter.Vertices, Bodies = Matter.Bodies; // create engine var engine = Engine.create(), world = engine.world; // create renderer var render = Render.create({ element: document.body, engine: engine, options: { width: Math.min(document.body.clientWidth, 1024), height: Math.min(document.body.clientHeight, 1024) } }); Render.run(render); // create runner var runner = Runner.create(); Runner.run(runner, engine); // scene code var stack = Composites.stack(100, 120, 25, 18, 0, 0, function(x, y) { return Bodies.rectangle(x, y, 25, 25); }); World.add(world, [ stack, Bodies.rectangle(400, 0, 800, 50, { isStatic: true }), Bodies.rectangle(400, 600, 800, 50, { isStatic: true }), Bodies.rectangle(800, 300, 50, 600, { isStatic: true }), Bodies.rectangle(0, 300, 50, 600, { isStatic: true }) ]); // add mouse control var mouse = Mouse.create(render.canvas), mouseConstraint = MouseConstraint.create(engine, { mouse: mouse, constraint: { stiffness: 0.2, render: { visible: false } } }); World.add(world, mouseConstraint); // keep the mouse in sync with rendering render.mouse = mouse; // fit the render viewport to the scene Render.lookAt(render, Composite.allBodies(world)); // context for MatterTools.Demo return { engine: engine, runner: runner, render: render, canvas: render.canvas, stop: function() { Matter.Render.stop(render); Matter.Runner.stop(runner); } }; };