chase camera (K)

k-drive version

by jason870509

HTML

<div id="info">K-drive
</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/109/three.min.js"></script>
<script src="https://threejs.org/examples/js/controls/OrbitControls.js">


</script>
<script src="https://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 camera, scene, renderer, mesh, controls;
var keyboard = new KeyboardState();
var clock;

var car;
var pos = new THREE.Vector3();
var vel, speed, angle;
// for PD control
var state = [0,0]; 
var tailVec = new THREE.Vector3 (-1,0,0);

(function() {
  Math.clamp = function(val, min, max) {
    return Math.min(Math.max(val, min), max);

  }
})();

init();
animate();

function buildVehicle() {
  var car = new THREE.Object3D();
  var mat = new THREE.MeshNormalMaterial();
  var body = new THREE.Mesh(new THREE.BoxGeometry(15, 2, 8), mat);
  car.add(body);
  var pointer = new THREE.Mesh(new THREE.BoxGeometry(10, 2, 2), mat);
  car.add(pointer);
  pointer.position.x = 5;
  return car;
}

function init() {

  clock = new THREE.Clock();
  scene = new THREE.Scene();

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

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

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

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

  controls.enableKeys = false;

  document.body.appendChild(renderer.domElement);
  ///////////////////////////////////////////////////////////////////
  speed = 5.0;
  angle = 0.0;

  car = buildVehicle();
  scene.add(car);

  tail = new THREE.Object3D();
  let tailMesh = new THREE.Mesh(new THREE.BoxGeometry(22, 1, 1),
    new THREE.MeshBasicMaterial({
      color: 0xffff34,
      transparent: true,
      opacity: 0.3
    }));
  tail.add(tailMesh);
  tailMesh.position.x = 11;
  scene.add (tail);
}

function update(dt) {

  keyboard.update();
  if (keyboard.pressed("left"))
    angle += 0.01;
  if (keyboard.pressed("right"))
    angle -= 0.01;
  if (keyboard.pressed("up"))
    speed += 0.5;
  if (keyboard.pressed("down"))
    speed -= 0.5;

  speed = Math.clamp(speed, 0.1, 20.0);
  vel = new...