纹理贴图的应用以及实现一个太阳系的自转公转
点击查看demo演示
demo地址：https://nsytsqdtn.github.io/demo/solar/solar
three.js中的纹理
纹理贴图是通过将图像应用到对象的一个或多个面，来为3D对象添加细节的一种方法。
可以使用TextureLoader类的load方法来加载纹理
function loadImgTexture(){
var loader = new THREE.TextureLoader();
loader.load("metal-rust.jpg",function(texture){
var geometry = new THREE.BoxGeometry(10,10,10);
var material = new THREE.MeshBasicMaterial({color:0x739783,map:texture});
mesh = new THREE.Mesh(geometry,material);
scene.add(mesh);
})
}实现效果如下：
八大行星的贴图资源网上到处都可以找到，这里给一个还不错的地址：
https://tieba.baidu.com/p/4876471245?red_tag=3235237836
完整太阳系代码：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Three.js</title>
<script src="../../Import/three.js"></script>
<script src="../../Import/stats.js"></script>
<script src="../../Import/Setting.js"></script>
<script src="../../Import/OrbitControls.js"></script>
<style type="text/css">
div#canvas-frame {
border: none;
cursor: pointer;
width: 100%;
height: 850px;
background-color: #333333;
}
</style>
</head>
<body onload="threeStart()">
<script>
let renderer;
function initThree() {
width = document.getElementById('canvas-frame').clientWidth;
height = document.getElementById('canvas-frame').clientHeight;
renderer = new THREE.WebGLRenderer({
antialias : true
});
renderer.setSize(width,height);
document.getElementById("canvas-frame").appendChild(renderer.domElement);
renderer.setClearColor(0x333333, 1.0);
}
let camera;
function initCamera() {
camera = new THREE.PerspectiveCamera(45, width / height, 1, 10000);
camera.position.x = 0;
camera.position.y = 500;
camera.position.z = 2000;
camera.up.x = 0;
camera.up.y = 1;
camera.up.z = 0;
camera.lookAt(0,0,0);
}
let scene;
function initScene() {
scene = new THREE.Scene();
let bgTexture = new THREE.TextureLoader().load("../../Image/universe.jpg");//背景贴图
scene.background = bgTexture;//把场景的背景设置为一张图片
}
let light;
function initLight() {
light = new THREE.PointLight(0xffffff,1);//点光源，模拟太阳
light.position.set(0,0,0);
scene.add(light);
light = new THREE.AmbientLight(0xffffff,0.3);//环境光
scene.add(light);
}
let sun;
let earth;
let tuxing;
let shuixing;
let jinxing;
let huoxing;
let muxing;
let tianwangxing;
let haiwangxing;
function initObject() {
let geometry = new THREE.SphereGeometry(15, 50, 50);
let texture = THREE.ImageUtils.loadTexture("../../Image/shuixing.jpg");//定义一个贴图，并从本地文件中加载
let material = new THREE.MeshBasicMaterial({map:texture});//把上面定义的texture设置为星球的纹理材质
shuixing = new THREE.Mesh(geometry,material);
shuixing.position.set(0,0,150);//3
scene.add(shuixing);
geometry = new THREE.SphereGeometry(25, 50, 50);
texture = THREE.ImageUtils.loadTexture("../../Image/jinxing.jpg");
material = new THREE.MeshBasicMaterial({map:texture});
jinxing = new THREE.Mesh(geometry,material);
jinxing.position.set(0,0,200);//4
scene.add(jinxing);
geometry = new THREE.SphereGeometry(30, 50, 50);
texture = THREE.ImageUtils.loadTexture("../../Image/earth.jpg");
material = new THREE.MeshBasicMaterial({map:texture});
earth = new THREE.Mesh(geometry,material);
earth.position.set(0,0,300);//6
scene.add(earth);
geometry = new THREE.SphereGeometry(20, 50, 50);
texture = THREE.ImageUtils.loadTexture("../../Image/huoxing.jpg");
material = new THREE.MeshBasicMaterial({map:texture});
huoxing = new THREE.Mesh(geometry,material);
huoxing.position.set(0,0,400);//8
scene.add(huoxing);
geometry = new THREE.SphereGeometry(65, 50, 50);
texture = THREE.ImageUtils.loadTexture("../../Image/muxing.jpg");
material = new THREE.MeshBasicMaterial({map:texture});
muxing = new THREE.Mesh(geometry,material);
muxing.position.set(0,0,600);//500 12
scene.add(muxing);
geometry = new THREE.TorusGeometry(80,6,20,20);
texture = THREE.ImageUtils.loadTexture("../../Image/muxinghuan.jpg");
material = new THREE.MeshBasicMaterial({map:texture});
let muxinghuan = new THREE.Mesh(geometry,material);
muxinghuan.rotation.x = 1.4;//木星环
muxing.add(muxinghuan);
geometry = new THREE.SphereGeometry(55, 50, 50);
texture = THREE.ImageUtils.loadTexture("../../Image/tuxing.jpg");
material = new THREE.MeshBasicMaterial({map:texture});
tuxing = new THREE.Mesh(geometry,material);
tuxing.position.set(0,0,800);//16
scene.add(tuxing);
geometry = new THREE.TorusGeometry(65,8,20,20);
texture = THREE.ImageUtils.loadTexture("../../Image/tuxinghuan.jpg");
material = new THREE.MeshBasicMaterial({map:texture});
let tuxinghuan = new THREE.Mesh(geometry,material);
tuxinghuan.rotation.x = 1.4;
tuxing.add(tuxinghuan);
geometry = new THREE.SphereGeometry(45, 50, 50);
texture = THREE.ImageUtils.loadTexture("../../Image/tianwangxing.jpg");
material = new THREE.MeshBasicMaterial({map:texture});
tianwangxing = new THREE.Mesh(geometry,material);
tianwangxing.position.set(0,0,950);//19
scene.add(tianwangxing);
geometry = new THREE.SphereGeometry(40, 50, 50);
texture = THREE.ImageUtils.loadTexture("../../Image/haiwangxing.jpg");
material = new THREE.MeshBasicMaterial({map:texture});
haiwangxing = new THREE.Mesh(geometry,material);
haiwangxing.position.set(0,0,1100);//22
scene.add(haiwangxing);
geometry = new THREE.SphereGeometry(120, 50, 50);
texture = THREE.ImageUtils.loadTexture("../../Image/sun.jpg");
material = new THREE.MeshBasicMaterial({map:texture,
emissive: 0xffffff,side: THREE.DoubleSide,});
sun = new THREE.Mesh(geometry,material);
sun.position.set(0,0,0);
scene.add(sun);
//在太阳外面设置一层透明的罩，看上去更像太阳
let canvas = document.createElement( 'canvas' );
canvas.width = 256;
canvas.height = 256;
let context = canvas.getContext( '2d' );
let gradient = context.createRadialGradient( canvas.width / 2, canvas.height / 2, 0, canvas.width / 2, canvas.height / 2, canvas.width / 2 );//创建一个圆形渐变对象
gradient.addColorStop( 0.1, 'rgba(255,60,0,0.01)' );//内圈的颜色
gradient.addColorStop( 1, 'rgba(255,125,0,0.5)' );//最外面的颜色
context.fillStyle = gradient;
context.fillRect( 0, 0, canvas.width, canvas.height );//将一个画布使用圆形渐变对象进行填充
let shadowTexture = new THREE.CanvasTexture( canvas );//把刚刚画好的画布拿来作为画布贴图
let shadowMaterial = new THREE.MeshBasicMaterial( { map: shadowTexture,transparent:true } );//用此贴图来当材质
let shadowGeo = new THREE.SphereGeometry( 130,50,50);
let shadowMesh;
shadowMesh = new THREE.Mesh( shadowGeo, shadowMaterial );
shadowMesh.position.y = 0;
shadowMesh.position.x = 0;
sun.add( shadowMesh );
//画线，把太阳系每个星球运行轨迹画出来
for(let j=3;j<=22;j++) {
if (j==3||j==4||j==6||j==8||j==12||j==16||j==19||j==22){
let radius = 50 * j;
let lineGeometry2 = new THREE.Geometry();
for (let i = 0; i <= 2 * Math.PI; i += Math.PI / 30) {
lineGeometry2.vertices.push(new THREE.Vector3(radius * Math.cos(i), 0, radius * Math.sin(i), 0))
}
let material2 = new THREE.LineBasicMaterial({color: 0x8f6cab})
let cycleMesh = new THREE.Line(lineGeometry2, material2);
cycleMesh.position.set(0, 0, 0);
scene.add(cycleMesh);
}
}
}
//每个星球的自转函数
function zizhuan() {
sun.rotation.y = sun.rotation.y+0.008>=2*Math.PI?0:sun.rotation.y+0.008;
shuixing.rotation.y = shuixing.rotation.y+0.005>=2*Math.PI?0:shuixing.rotation.y+0.005;
jinxing.rotation.y = jinxing.rotation.y+0.003>=0?2*Math.PI:jinxing.rotation.y+0.003;
earth.rotation.y = earth.rotation.y+0.012>=2*Math.PI?0:earth.rotation.y+0.012;
huoxing.rotation.y = huoxing.rotation.y+0.01>=2*Math.PI?0:huoxing.rotation.y+0.01;
tuxing.rotation.y = tuxing.rotation.y+0.04>=2*Math.PI?0:tuxing.rotation.y+0.06;
muxing.rotation.y = muxing.rotation.y+0.03>=2*Math.PI?0:muxing.rotation.y+0.08;
tianwangxing.rotation.z = tianwangxing.rotation.z+0.015>=2*Math.PI?0:tianwangxing.rotation.z+0.015;
haiwangxing.rotation.y = haiwangxing.rotation.y+0.02>=2*Math.PI?0:haiwangxing.rotation.y+0.02;
}
let shuixingAngle = 0;
let jinxingAngle = 0;
let earthAngle = 0;
let huoxingAngle = 0;
let tuxingAngle = 0;
let muxingAngle = 0;
let tianwangxingAngle = 0;
let haiwangxingAngle = 0;
//每个星球的公转函数
function gongzhuan() {
shuixingAngle = shuixingAngle+0.03>=2*Math.PI?0:shuixingAngle +0.03;
shuixing.position.set(150*Math.sin(shuixingAngle)
,0,150*Math.cos(shuixingAngle));
jinxingAngle = jinxingAngle-0.02>=0?2*Math.PI:jinxingAngle -0.02;
jinxing.position.set(200*Math.sin(jinxingAngle)
,0,200*Math.cos(jinxingAngle));
earthAngle = earthAngle+0.015>=2*Math.PI?0:earthAngle +0.015;
earth.position.set(300*Math.sin(earthAngle)
,0,300*Math.cos(earthAngle));
huoxingAngle = huoxingAngle+0.01>=2*Math.PI?0:huoxingAngle +0.01;
huoxing.position.set(400*Math.sin(huoxingAngle)
,0,400*Math.cos(huoxingAngle));
muxingAngle = muxingAngle+0.006>=2*Math.PI?0:muxingAngle +0.006;
muxing.position.set(600*Math.sin(muxingAngle)
,0,600*Math.cos(muxingAngle));
tuxingAngle = tuxingAngle+0.004>=2*Math.PI?0:tuxingAngle +0.004;
tuxing.position.set(800*Math.sin(tuxingAngle)
,0,800*Math.cos(tuxingAngle));
tianwangxingAngle = tianwangxingAngle+0.003>=2*Math.PI?0:tianwangxingAngle +0.003;
tianwangxing.position.set(950*Math.sin(tianwangxingAngle)
,0,950*Math.cos(tianwangxingAngle));
haiwangxingAngle = haiwangxingAngle+0.002>=2*Math.PI?0:haiwangxingAngle +0.002;
haiwangxing.position.set(1100*Math.sin(haiwangxingAngle)
,0,1100*Math.cos(haiwangxingAngle));
}
function initSetting() {
loadAutoScreen(camera,renderer);
loadFullScreen();
loadStats();
}
let controller;
function threeStart() {
initThree();
initCamera();
initScene();
initLight();
initObject();
initSetting();
controller = new THREE.OrbitControls(camera,renderer.domElement);
controller.target = new THREE.Vector3(0,0,0);
controller.autoRotate = true;
animation();
}
function animation() {
zizhuan();
gongzhuan();
renderer.clear();
renderer.render(scene,camera);
requestAnimationFrame(animation);
stats.update();
}
</script>
<div id="canvas-frame"></div>
</body>
</html>注意从本地读取图片或者其他文件时，浏览器一般是不允许的，所以会出现加载不了纹理或者背景图片的情况，只能在Chrome浏览器的属性--目标的最后，加上 --allow-file-access-from-files（前面有一个空格），就可以从这个打开的快捷方式中去读取到本地文件，如果是Edge浏览器似乎就直接可以。也可以使用npm或者tomcat搭建一个本地服务器，然后把图片放进去就可以直接读取了。