three.js模拟实现太阳系行星体系

 1 // 初始化场景
 2 var scene = new THREE.Scene();
 3 // 初始化相机，第一个参数为摄像机视锥体垂直视野角度，第二个参数为摄像机视锥体长宽比，
 4 // 第三个参数为摄像机视锥体近端面，第四个参数为摄像机视锥体远端面
 5 var camera = new THREE.PerspectiveCamera(20, dom.clientWidth / dom.clientHeight, 1, 100000);
 6 // 设置相机位置，对应参数分别表示x，y，z位置
 7 camera.position.set(0, 0, 500);
 8 var renderer = new THREE.WebGLRenderer({
 9       alpha: true,
10       antialias: true
11 });

1 // 设置窗口尺寸，第一个参数为宽度，第二个参数为高度
2 renderer.setSize(dom.clientWidth, dom.clientHeight);
3 // 初始化控制器
4 var orbitcontrols = new THREE.OrbitControls(camera,renderer.domElement);
5 // 将渲染器加载到dom中
6 dom.appendChild(renderer.domElement);

1 // 定义太阳材质
2 var sunTexture = THREE.ImageUtils.loadTexture(‘./image/sun_bg.jpg‘, {}, function () {
3     renderer.render(scene, camera);
4 });
5 // 太阳以及太阳材质设定
6 centerBall = new THREE.Mesh(new THREE.SphereGeometry(30, 30, 30), new THREE.MeshBasicMaterial({
7     map: sunTexture
8 }));
9 scene.add(centerBall);

 1 /**
 2  * 实现球体发光
 3  * @param color 颜色的r,g和b值,比如：“123,123,123”;
 4  * @returns {Element} 返回canvas对象
 5  */
 6 var generateSprite = function (color) {
 7     var canvas = document.createElement(‘canvas‘);
 8     canvas.width = 16;
 9     canvas.height = 16;
10     var context = canvas.getContext(‘2d‘);
11     var gradient = context.createRadialGradient(canvas.width / 2, canvas.height / 2, 0, canvas.width / 2, 
12     canvas.height / 2, canvas.width / 2);
13     gradient.addColorStop(0, ‘rgba(‘ + color + ‘,1)‘);
14     gradient.addColorStop(0.2, ‘rgba(‘ + color + ‘,1)‘);
15     gradient.addColorStop(0.4, ‘rgba(‘ + color + ‘,.6)‘);
16     gradient.addColorStop(1, ‘rgba(0,0,0,0)‘);
17     context.fillStyle = gradient;
18     context.fillRect(0, 0, canvas.width, canvas.height);
19     return canvas;
20 };
21 // 添加太阳发光效果
22 var centerBallLite = new THREE.Sprite(new THREE.SpriteMaterial({
23     map: new THREE.CanvasTexture(generateSprite(sunSpriteColor)),
24     blending: THREE.AdditiveBlending
25 }));
26 centerBallLite.scale.x = centerBallLite.scale.y = centerBallLite.scale.z = sunScaleSize;
27 scene.add(centerBallLite);

/**
 * 返回行星轨道的组合体
 * @param starLiteSize 行星的大小
 * @param starLiteRadius 行星的旋转半径
 * @param rotation 行星组合体的x,y,z三个方向的旋转角度
 * @param speed 行星运动速度
 * @param imgUrl 行星的贴图
 * @param scene 场景
 * @returns {{satellite: THREE.Mesh, speed: *}} 卫星组合对象;速度
*/
var initSatellite = function (starLiteSize, starLiteRadius, rotation, speed, imgUrl, scene) {
var track = new THREE.Mesh(new THREE.RingGeometry(starLiteRadius, starLiteRadius + 0.05, 50, 1), new THREE.MeshBasicMaterial());
var centerMesh = new THREE.Mesh(new THREE.SphereGeometry(1, 1, 1), new THREE.MeshLambertMaterial()); //材质设定
var starLite = new THREE.Sprite(new THREE.SpriteMaterial({
     map: THREE.ImageUtils.loadTexture(imgUrl)
}));
starLite.scale.x = starLite.scale.y = starLite.scale.z = starLiteSize;
starLite.position.set(starLiteRadius, 0, 0);
var pivotPoint = new THREE.Object3D();
pivotPoint.add(starLite);
pivotPoint.add(track);
centerMesh.add(pivotPoint);
centerMesh.rotation.set(rotation.x, rotation.y, rotation.z);
scene.add(centerMesh);
   return {starLite: centerMesh, speed: speed};
};

 1 // 执行函数
 2 var render = function () {
 3     renderer.render(scene, camera);
 4     centerBall.rotation.y -= 0.01;
 5     for (var i = 0; i < starLites.length; i++) {
 6         starLites[i].starLite.rotation.z -= starLites[i].speed;
 7     }
 8     orbitcontrols.update();
 9     requestAnimationFrame(render);
10 }