Cezary Wojcik
Keyboard Wizard
Spotlight: Three.js

July 19, 2013

Recently, I've begun messing with an amazing framework called Three.js. Three.js is a JavaScript framework that can produce WebGL and Canvas-based 3D elements. It is completely open-sourced with plenty of examples.

I want to show a really simple example of Three.js that renders a simple cube.

Suppose we have the following little bit of html:

<div id="three"></div>

Assuming we've downloaded Three.js and included the JavaScript file in the HTML page, all we need to display a simple spinning cube is the following code:

// our DOM element
var el = document.getElementById("three");

// size
var width = 250;
var height = 250;

// field of view
var fov = 60;

// near render limit
var near = 0.1;

// far render limit
var far = 10;

// Three.js Canvas Renderer (WebGLRenderer also available)
var renderer = new THREE.CanvasRenderer();
renderer.setSize(width, height);

// Three.js scene
var scene = new THREE.Scene();

// Three.js camera
var camera = new THREE.PerspectiveCamera(fov, width/height, near, far);
camera.position.y = 2;

// Three.js material
var material = new THREE.MeshNormalMaterial();

// Three.js geometry
var geometry = new THREE.CubeGeometry(1, 1, 1);

// Three.js cube mesh
var cube = new THREE.Mesh(geometry, material);

// add cube to scene

// call render function

// render function
function render() {
  renderer.render(scene, camera);

  // animate the cube every frame
  cube.rotation.x += 0.01;
  cube.rotation.z += 0.02;


And now, we have the following result:

The code is really fairly self-explanatory - the simplicity of Three.js was fairly startling to me when I first learned about the framework.

In this example, I used CanvasRenderer instead of WebGLRenderer so that this cube can also be seen on mobile devices. WebGL has far better performance (because WebGL is allowed to use the GPU for processing, whereas Canvas is not) and a larger feature set, especially when it comes to lighting/shaders, but for this small sample, it doesn't make a difference.

I'm hoping that WebGL becomes a supported feature in mobile devices. I believe that there are beta versions of Chrome available on Android devices that do support WebGL, but as an Apple user, I'm hoping that support comes to the iPhone and iPad soon.