Three.js呈现3D效果机房-初步方案[通俗易懂]

大家好，又见面了，我是你们的朋友全栈君。

3D机房系统是最近用户的需求,通过相关了解最后使用Three.js,也发现最近有东西可以写出来分享：

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);