The aim of the project is to create a lightweight 3D library with a very low level of complexity — in other words, for dummies. The library provides <canvas>, <svg>, CSS3D and WebGL renderers.
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Download the minified library and include it in your html. Alternatively see how to build the library yourself.
<script src="js/three.min.js"></script>This code creates a scene, then creates a camera, adds the camera and cube to the scene, creates a <canvas> renderer and adds its viewport in the document.body element.
<script>
	var camera, scene, renderer;
	var geometry, material, mesh;
	init();
	animate();
	function init() {
		camera = new THREE.PerspectiveCamera( 75, window.innerWidth / window.innerHeight, 1, 10000 );
		camera.position.z = 1000;
		scene = new THREE.Scene();
		geometry = new THREE.BoxGeometry( 200, 200, 200 );
		material = new THREE.MeshBasicMaterial( { color: 0xff0000, wireframe: true } );
		mesh = new THREE.Mesh( geometry, material );
		scene.add( mesh );
		renderer = new THREE.CanvasRenderer();
		renderer.setSize( window.innerWidth, window.innerHeight );
		document.body.appendChild( renderer.domElement );
	}
	function animate() {
		// note: three.js includes requestAnimationFrame shim
		requestAnimationFrame( animate );
		mesh.rotation.x += 0.01;
		mesh.rotation.y += 0.02;
		renderer.render( scene, camera );
	}
</script>If everything went well you should see this.