Turret(atan2)

by 蔡 育曄

HTML

<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="https://code.jquery.com/jquery-2.1.4.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/stats.js/r16/Stats.min.js"></script>
<script src="https://jyunming-chen.github.io/tutsplus/js/KeyboardState.js"></script>

CSS

body {
  overflow: hidden;
}

JavaScript

class Ball {
  constructor (mass = 1, radius=38/Math.PI, friction = 0) {
    this.type = 'ball';
    this.mass = mass;  // may need to differentiate basketball & bowling ball
    this.radius = radius;
    this.friction = friction;  // for contact

    // for dynamics calculation
    this.pos = new THREE.Vector3();
    this.vel = new THREE.Vector3();
    this.initV =  new THREE.Vector3();
    this.force = new THREE.Vector3();
    this.count = 0;

    this.obj = new THREE.Object3D();
    loader.setCrossOrigin ('');
    let mesh = new THREE.Mesh (new THREE.SphereGeometry(radius, 32, 32), new THREE.MeshLambertMaterial({map:loader.load("https://i.imgur.com/Sw4OGXN.png")}))
    this.obj.add (mesh)
    scene.add (this.obj)
  }

  update(dt) {

    // after GLOBAL collision & contact
    this.vel.add (this.force.clone().multiplyScalar(dt))
    this.pos.add (this.vel.clone().multiplyScalar(dt)) 
    this.obj.position.copy (this.pos);
    if(this.obj.position.y <this.radius) {
       this.pos.set(-20,this.radius,30);
        this.vel.copy(ball.initV);
         update = !update;
    }  
  }

  // useless API
  moveTo(thePos) {
    this.pos.copy (thePos);
    this.obj.position.copy (this.pos);
  }

  rotateTo (theta) {  // abs CCW angle
    this.obj.rotation.z = theta;
    //this.normal.applyEuler (new THREE.Euler (0,0,theta))
  }
}

var renderer, camera, controls, scene, axes, stats;
var d, v0, theta,tmpV;
var loader = new THREE.TextureLoader();
var target, point, pp,power,prevPower;
var ball,tmp =true;
var update = false;
var keyboard = new KeyboardState();
var line, pLine, chargeUp = false;
var raycaster,pickables;
var reset = false;
init();
animate();

function makeLine(d) {
  let dt = 0.002;
  let geometry = new THREE.Geometry();
  let check = false
  for(pp=0; ball.pos.y >  ball.radius||!check;pp++) {
    geometry.vertices.push (new THREE.Vector3(ball.pos.x,ball.pos.y,ball.pos.z)); 
    ball.vel.add (ball.force.clone().multiplyScalar(dt))
    ball.pos.add...