Rotate Arm

by Alan Lin

HTML

<div id="info">two-link arm with end effector
  <br/>
  <br/>
  <a>Press "A" and "D" to move arm</a>
  <br/>
  <a>Press "W" and "S" to move arm2</a>
</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r70/three.min.js"></script>
<script src="https://jyunming-chen.github.io/tutsplus/js/KeyboardState.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 arm, arm2;
var angle = 0, angle2 = 0;
var endEffector;
var keyboard = new KeyboardState();

init();
animate();

function init() {

  scene = new THREE.Scene();

  camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 1, 10000);
  camera.position.z = 200;
  camera.position.y = 200;
  scene.add(camera);

  arm = new THREE.Object3D();
  scene.add(arm);

  endEffector = new THREE.Mesh(new THREE.SphereGeometry(5, 10, 10),
    new THREE.MeshLambertMaterial({
      color: 0xff1234
    }));
  scene.add(endEffector);

  var mesh = new THREE.Mesh(new THREE.BoxGeometry(20, 5, 5),
    new THREE.MeshLambertMaterial());
  mesh.position.set(10, 2.5, 0);
  arm.add(mesh);

  arm2 = arm.clone();
  arm2.position.set(20, 0, 0);
  arm.add(arm2);

  console.log(arm2);

  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);

}

function animate() {

  var eepos = arm2.children[0].localToWorld(new THREE.Vector3(12, 0, 0));
  endEffector.position.copy(eepos);
  
  if (keyboard.down("A")) {
  		angle += 0.1;
  		arm.rotation.y = angle;;
  } 
  else if (keyboard.down("D")) {
  		angle -= 0.1;
      arm.rotation.y = angle;
  } 
  else if (keyboard.down("W")) {
  		angle2 += 0.1;
  		arm2.rotation.y = angle2;
  } 
  else if (keyboard.down("S")) {
  		angle2 -= 0.1;
  		arm2.rotation.y = angle2;
  } 
	keyboard.update();
  controls.update();
  requestAnimationFrame(animate);
  render();
}

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