一、页面效果

二、技术选择

中间的建筑相关的显示和效果都是threejs实现的

左右两侧用的是echarts

三、代码结构

1. 画布

用js自己创建一个放置画布的div

container = document.createElement(‘div‘)

document.body.appendChild(container)

2. 场景的创建

之后的比如几何体 摄像机 光源都是放在场景里面

scene = newTHREE.Scene();

renderer= new THREE.WebGLRenderer({ antiakuas: true})

renderer.setClearColor(new THREE.Color("rgba(3,19,52)"), 1)//整个画布的背景颜色

renderer.setSize(window.innerWidth, window.innerHeight)

renderer.shadowMapEnabled= true;//需要阴影映射

container.appendChild(renderer.domElement)

3. 摄像机

摄像机是有两种类型的

透视投影摄像机:PerspectiveCamera会让物体近大远小；

正交投影摄像机：OrthographicCamera物体渲染的大小是一致的；

camera = new THREE.PerspectiveCamera(90, window.innerWidth / window.innerHeight, 1, 1000)

camera.position.set(0, 150, 300)//相机位置

camera.lookAt(new THREE.Vector3(0, 0, 0))//相机观看物体的位置

4.光源

光有基本的四种类型：

环境光( AmbientLight )：笼罩在整个空间无处不在的光

点光源( PointLight )：向四面八方发射的单点光源

聚光灯( SpotLight )：发射出锥形状的光， 模拟手电筒，台灯等光源

平行光( DirectinalLight )：平行的一束光，模拟从很远处照射的太阳光

var ambientLight = new THREE.AmbientLight(0x606060)//环境光

scene.add(ambientLight)var spotLight = new THREE.SpotLight(0xffffff)

spotLight.position.set(200, 160, 85)

spotLight.castShadow= truescene.add(spotLight)

5.创建栅格平面

Geometry这是存储几何体相关的信息，是为了减少CPU的消耗

栅格用的是线段画出来的

function plane() {var geometry = newTHREE.Geometry();

geometry.vertices.push(new THREE.Vector3(-800, 0, 0));

geometry.vertices.push(new THREE.Vector3(800, 0, 0));for (var i = 0; i < 50; i++) {var line = new THREE.Line(geometry, new THREE.LineBasicMaterial({ color: "rgba(38,55,84,1)", opacity: 1}));

line.position.z= (i * 50) - 800;

scene.add(line);var line = new THREE.Line(geometry, new THREE.LineBasicMaterial({ color: "rgba(38,55,84,1)", opacity: 1}));

line.position.x= (i * 50) - 800;

line.rotation.y= 90 * Math.PI / 180;

scene.add(line);

}

}

6.建筑

建筑用的是立方体，需要注意的是可以自己设置一个图片，然后将图片作为纹理贴到立方体上面来；

根据移动立方体的位置，来拼合成建筑；

var loader = newTHREE.TextureLoader();

loader.load("./img/cude1.png", (texture) =>{var geometry = new THREE.BoxGeometry(30, 5, 20);var material = new THREE.MeshBasicMaterial({ color: 0x739783, map: texture });

buildArr[i]= newTHREE.Mesh(geometry, material);

buildArr[i].position.x= 10buildArr[i].position.y= 5 + i * 5buildArr[i].position.z= -10scene.add(buildArr[i]);

})

7.视角的移动

当我们看到视角的远近，其实是摄像机的移动，我们通过修改摄像机的位置，来达到响应的目的；

var cameraz = 10;var camerax = 10;vartimer;

timer=setInterval(function () {

cameraz+= 1camerax+= 1camera.position.x= 50 -cameraz

camera.position.z= 100 +camerazif (cameraz >= 300 && camerax >= 50) {

clearInterval(timer)

}

},30)for (var i = 0; i < 30; i++) {

buildArr[i].position.y= 5 + i * 5}

8.车流

我们先是设置一下管道的几何体和小球，然后同样的修改小球的x y z值来进行流动，需要注意的是小球需要根据管道的路径进行流动，

var curve = newTHREE.CatmullRomCurve3([new THREE.Vector3(-150, 2, -280),new THREE.Vector3(-110, 2, -50),new THREE.Vector3(-10, 2, 0),new THREE.Vector3(100, 2, 100),new THREE.Vector3(140, 2, 200)

],false/*是否闭合*/);

function traffic() {//一条

var tubeGeometry2 = new THREE.TubeGeometry(curve, 100, 2, 50, false);var tubeMaterial2 = newTHREE.MeshPhongMaterial({

color:"rgb(45,245,216)",

transparent:true,

opacity:1,

});var tube2 = newTHREE.Mesh(tubeGeometry2, tubeMaterial2);

scene.add(tube2);//物体

geometryP= new THREE.BoxGeometry(5, 5, 5);var materialP = new THREE.MeshBasicMaterial({ color: ‘rgb(165,244,7)‘});

circleP= newTHREE.Mesh(geometryP, materialP);

scene.add(circleP);

geometryP.rotateY(Math.PI/ 2);//circleP.position.set(-80, -40, 0);

}if (progress > 1.0) {

circleP.position.set(-150, 2, -280);

progress= 0

//return;//停留在管道末端,否则会一直跑到起点 循环再跑

}

progress+= 0.001; //0.0009;

if(curve) {

let point=curve.getPoint(progress);if (point &&point.x) {

circleP.position.set(point.x, point.y, point.z);

}

}

9.事件

window.addEventListener("click", onDocumentMouseMove, false)

四、相关资料

原文：https://www.cnblogs.com/GainLoss/p/12706530.html