webGL可以让我们在canvas上实现3D效果。而three.js是一款webGL框架，由于其易用性被广泛应用
Three.js是通过对WebGL接口的封装与简化而形成的一个易用的图形库
分步实现3D效果
初始化3D模型参数
开始搭建场景
初始化渲染器
初始化摄像机
创建场景
灯光布置
创建网格线
循环渲染界面
创建鼠标控制器
添加对象到场景中
一 . 初始化3D模型参数
//参数处理 this.option = new Object(); this.option.antialias = option.antialias || true; this.option.clearCoolr = option.clearCoolr || 0x1b7ace; this.option.showHelpGrid = option.showHelpGrid || false; //对象 this.id = id; this.width = width(); this.height = height(); this.renderer = null;//渲染器 this.scene = null;//场景 this.camera = null;//摄像机 this.selected=null; this.objects = []; this.mouseClick = new THREE.Vector2(); this.raycaster = new THREE.Raycaster(); this.controls = null;//鼠标控制器 this.trsnaformControls = null;//鼠标控制器 this.dragcontrols = null; this.objList = json.objects;//对象列表 this.eventList = json.events;//事件对象列表 this.dragList = []; this.objectStatusList = {}; this.clickList = []; var that = this;
对于一些需要使用的参数,开始加载进行初始化操作。
二 . 开始搭建场景
搭建场景包含一些具体的初始化操作 一些初始化方法(之后才对具体方法加以说明)：
var that = this; room3dObj = that; that.initThree(that.id); //初始化渲染器 that.initCamera(); //初始化摄像机 that.initScene();//创建场景 that.initHelpGrid();//创建网格 that.initLight();//灯光布置 //添加3D对象 $.each(that.objList, function (index,obj) { that.InitAddObject(obj);//添加对象到场景中 }); that.initMouseCtrl();//创建鼠标控制器 that.animation();//循环渲染界面
三 . 初始化渲染器
渲染器 WebGLRenderer 定义语法：
var that = this; that.renderer = new THREE.WebGLRenderer({ alpha: true, antialias: that.option.antialias }); that.renderer.setSize(that.width, that.height); $(“#” + that.id).append(that.renderer.domElement); that.renderer.setClearColor(that.option.clearCoolr, 1.0); that.renderer.shadowMap.enabled = true; that.renderer.shadowMapSoft = true; //事件 that.renderer.domElement.addEventListener(‘mousedown',that.onDocumentMouseDown, false); that.renderer.domElement.addEventListener(‘mousemove',that.onDocumentMouseMove, false);
四 . 初始化摄像机
采用PerspectiveCamera 相机：
var that = this; that.camera = new THREE.PerspectiveCamera(45, that.width / that.height, 1, 100000); that.camera.name = 'mainCamera'; that.camera.position.x =0; that.camera.position.y =2000; that.camera.position.z =1800; that.camera.up.x = 0; that.camera.up.y =1; that.camera.up.z =0; that.camera.lookAt({ x: 100, y: 0, z: 100 }); that.objects.push(that.camera); that.dragList.push(that.camera); that.clickList.push(that.camera);
五 . 创建场景
var that = this; that.scene = new THREE.Scene();
六 . 灯光布置
/* AmbientLight: 环境光，基础光源，它的颜色会被加载到整个场景和所有对象的当前颜色上。 PointLight：点光源，朝着所有方向都发射光线 SpotLight ：聚光灯光源：类型台灯，天花板上的吊灯，手电筒等 DirectionalLight：方向光，又称无限光，从这个发出的光源可以看做是平行光. */ var that = this; var light = new THREE.AmbientLight(0xcccccc); light.position.set(0, 0,0); that.scene.add(light); var light2 = new THREE.PointLight(0x555555); light2.shadow.camera.near =1; light2.shadow.camera.far = 5000; light2.position.set(0, 350, 0); light2.castShadow = true;//表示这个光是可以产生阴影的 that.scene.add(light2);
七 . 创建网格
var that = this; if (that.option.showHelpGrid) { var helpGrid = new THREE.GridHelper(1000, 50); that.scene.add(helpGrid); }
八 . 循环渲染界面
var that = room3dObj; if (TWEEN != null && typeof (TWEEN) != ‘undefined') { TWEEN.update(); } requestAnimationFrame(that.animation); that.renderer.render(that.scene, that.camera);
九 . 创建鼠标控制器
var that = this; that.controls = new THREE.OrbitControls(that.camera,that.renderer.domElement); that.controls.addEventListener(‘change', that.updateControls);
十 . 添加对象到场景中
var that = room3dObj; that.scene.add(obj); that.objects.push(obj);
最后效果
