raycaster:pick

by jmchen

HTML

<div id="info">Picking Demo</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

#info {
    position: absolute;
    top: 0px;
    width: 100%;
    padding: 10px;
    text-align: center;
    color: #ffff00
}

JavaScript

var camera, scene, renderer, light, controls;
var cube1, cube2, sphere;

var raycaster;
var mouse = new THREE.Vector2();
var pickables = [];

init();
animate();

function init() {
    scene = new THREE.Scene();

    camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 1, 1000);
    camera.position.z = 500;
    scene.add(camera);

    var geometry = new THREE.BoxGeometry(20, 20, 20);

    // clone wont work ... seems to retain the same material
    var cube1 = new THREE.Mesh(geometry, new THREE.MeshLambertMaterial({
        color: 0xff1234
    }));
    cube1.position.x = -60;

    var cube2 = new THREE.Mesh(geometry, new THREE.MeshLambertMaterial({
        color: 0x2134ff
    }));
    
    // test whether Object3D is pickable
    var cubeGroup = new THREE.Object3D();
    cubeGroup.add (cube2);
    cubeGroup.position.x = 60;
    
    sphere = new THREE.Mesh(new THREE.SphereGeometry(10), new THREE.MeshLambertMaterial());

    scene.add(cube1);
    scene.add(cubeGroup);
    scene.add(sphere);
    
    pickables = [cube1, cubeGroup];
    // note that cubeGroup (an Object3D) is not pickable!!!
    cube1.name = "cube1";
    cube2.name = "cube2";

    light = new THREE.PointLight(0xffffff);
    light.position.set(100, 300, 200);
    scene.add(light);

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

    renderer = new THREE.WebGLRenderer();
    renderer.setSize(window.innerWidth, window.innerHeight);
    renderer.setClearColor(0x888888);

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

    document.body.appendChild(renderer.domElement);

    raycaster = new THREE.Raycaster();
	document.addEventListener( 'mousedown', onDocumentMouseDown, false );
	document.addEventListener( 'mousemove', onDocumentMouseMove, false );
}

function onDocumentMouseDown( event ) {

	// PICKING DETAILS: 
	// convert mouse.xy = [-1,1]^2 (NDC)
	//...