Pick (raycaster)

orthographic & perspective cameras

by Bai Shiuan Huang

HTML

<div id="info">Picking Demo
  <br> press ENTER to change camera
</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/84/three.min.js"></script>
<script src="https://threejs.org/examples/js/controls/OrbitControls.js">
</script>
<script src="http://jyunming-chen.github.io/tutsplus/js/KeyboardState.js"></script>

CSS

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

body {
  overflow: hidden;
}

JavaScript

var scene, renderer, light, cube1, cube2, sphere;
var raycaster;
var mouse = new THREE.Vector2();
var pickables = [];
var keyboard = new KeyboardState();
var camera, cameraP, cameraO, controls, controls2;

init();
animate();

function init() {

  scene = new THREE.Scene();

  cameraP = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 1, 1000);
  cameraO = new THREE.OrthographicCamera(-100, 100, 100, -100, -10, 1000);
  cameraP.position.z = 500;
  cameraO.position.z = 500;

  camera = cameraP;
  renderer = new THREE.WebGLRenderer();
  renderer.setSize(window.innerWidth, window.innerHeight);
  renderer.setClearColor(0x888888);
  document.body.appendChild(renderer.domElement);

  controls = new THREE.OrbitControls(cameraP, renderer.domElement);
  controls2 = new THREE.OrbitControls(cameraO, renderer.domElement);

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

  var gridXZ = new THREE.GridHelper(200, 20, 'red', 'white');
  scene.add(gridXZ);

  //////////////////////////////////////////////////////////
  cube1 = new THREE.Mesh(new THREE.BoxGeometry(20, 20, 20),
    new THREE.MeshLambertMaterial({
      color: 0xff1234
    }));
  cube1.position.x = -60;
  scene.add(cube1);

  cube2 = cube1.clone();
  cube2.material = new THREE.MeshLambertMaterial({
    color: 0x2134ff
  });
  cube2.position.x = 60;
  scene.add(cube2);
  pickables.push(cube1, cube2);

  sphere = new THREE.Mesh(new THREE.SphereGeometry(10), new THREE.MeshLambertMaterial());
  scene.add(sphere);

  cube1.name = "cube1";
  cube2.name = "cube2";

  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)
  // unproject (mouse.xy, 1) to a point on the far plane (in world coordinate)
  // set raycaster (origin,...