solar system

sun, earth, moon Hiearchical Structure practice

by Wai Ting Chen

HTML

<div id="info">demo page</div>
<div id="info2">demo page</div>
<script src="//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: #ff0000
}

#info2 {
    position: absolute;
    top: 10px;
    width: 100%;
    padding: 10px;
    text-align: center;
    color: #00ff00
}

JavaScript

var camera, scene, renderer, sun, earth, angle = 0, angleS = 0,
    angle2S = 0, clock, control;

init();
animate();

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

    camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 1, 1000);
    camera.position.y = 100;
    camera.position.z = 400;
    
    scene.add(camera);

    sun = new THREE.Mesh(new THREE.SphereGeometry(20),
    new THREE.MeshBasicMaterial({
        wireframe: true
    }));

    earth = new THREE.Mesh(new THREE.SphereGeometry(10),
    new THREE.MeshBasicMaterial({
        wireframe: true
    }));
    moon = new THREE.Mesh(new THREE.SphereGeometry(3),
    new THREE.MeshBasicMaterial({
        wireframe: true
    }));
    
    //very important
    //there are Kinematics of Hiearchical Structure
    //every objest`s frame are base on it`s father
    //if not father, it base on warld frame
    earth.add(moon);
    sun.add(earth);
    scene.add(sun);

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

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

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

    control = new THREE.OrbitControls(camera, renderer.domElement);
    document.body.appendChild(renderer.domElement);
    window.addEventListener('resize', onWindowResize, false);
}

function onWindowResize() {
    camera.aspect = window.innerWidth / window.innerHeight;
    camera.updateProjectionMatrix();
    renderer.setSize(window.innerWidth, window.innerHeight);
}

function animate() {
    control.update();
    requestAnimationFrame(animate);
    render();
}

/*note! the frame are base on it`s father or world frame(no father)*/
function render() {
    //et the seconds passed since the clock started.
   ...