billboard

HTML

<div id="info">Billboard</div>
<script src="http://cdnjs.cloudflare.com/ajax/libs/three.js/r70/three.min.js"></script>
<script src="https://dl.dropboxusercontent.com/u/3587259/Code/Threejs/OrbitControls.js">
    
</script>

CSS

body {
	    background-color: #fff;
	    color: #111;
	    margin: 0px;
	    overflow: hidden;
	    font-family: Monospace;
	    font-size: 20px;
	    position: absolute;
	}
	#info {
	    position: absolute;
	    top: 0px;
	    width: 100%;
	    padding: 5px;
	    text-align: center;
	    color: #ffff00
	}

JavaScript

var scene, renderer, camera, controls;
var tree, tree2;

init();
animate();

function init() {
    var width = window.innerWidth;
    var height = window.innerHeight;

    renderer = new THREE.WebGLRenderer({
        antialias: true
    });
    renderer.setSize(width, height);
    renderer.setClearColor(0x888888);
    document.body.appendChild(renderer.domElement);

    scene = new THREE.Scene();

    camera = new THREE.PerspectiveCamera(45, width / height, 1, 10000);
    camera.position.y = 160;
    camera.position.z = 400;
    camera.lookAt(new THREE.Vector3(0, 0, 0));

    controls = new THREE.OrbitControls(camera, renderer.domElement);

    var gridXZ = new THREE.GridHelper(100, 10);
    gridXZ.setColors(new THREE.Color(0xff0000), new THREE.Color(0xffffff));
    scene.add(gridXZ);

    var pointLight = new THREE.PointLight(0xffffff);
    pointLight.position.set(0, 300, 200);
    scene.add(pointLight);

    var ambientLight = new THREE.AmbientLight(0x111111);
    scene.add(ambientLight);

    //////////////////////////////////////////////////////////////////////////////
    THREE.ImageUtils.crossOrigin = '';
    material = new THREE.MeshBasicMaterial({
        side: THREE.DoubleSide,
        transparent: true, // key to cutout texture
        map: THREE.ImageUtils.loadTexture('http://i.imgur.com/ltrHUSu.png')
    });

    tree = new THREE.Mesh (new THREE.PlaneGeometry (40,40), material);
    scene.add(tree);
    
    tree2 = tree.clone();
    scene.add (tree2);
}

function animate() {
    requestAnimationFrame(animate);
    controls.update();
    
    /////////////////////////////////////////////////////////////////////////////
    tree.position.set (50,20,0);
    rotateBillboard (tree);

    tree2.position.set (-30,20,20);
    rotateBillboard (tree2);
    /////////////////////////////////////////////////////////////////////////////
    
    render();
}

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

function rotateBillboard (mesh)
{
    var b =...