代码仓
GitHub - TiffanyHoo/three_practices: Learning three.js together!
可自行clone，无需安装依赖，直接liver-server运行/直接打开chapter01中的html文件
运行效果图
知识要点
核心运行代码
javascript
<!DOCTYPE html>
<html>
<head>
<title>Example 03.02 - point Light</title>
<script type="text/javascript" src="../libs/three.js"></script>
<script type="text/javascript" src="../libs/stats.js"></script>
<script type="text/javascript" src="../libs/dat.gui.js"></script>
<style>
body {
/* set margin to 0 and overflow to hidden, to go fullscreen */
margin: 0;
overflow: hidden;
}
</style>
</head>
<body>
<div id="Stats-output">
</div>
<!-- Div which will hold the Output -->
<div id="WebGL-output">
</div>
<!-- Javascript code that runs our Three.js examples -->
<script type="text/javascript">
// once everything is loaded, we run our Three.js stuff.
function init() {
// create a scene, that will hold all our elements such as objects, cameras and lights.
var scene = new THREE.Scene();
// create a camera, which defines where we're looking at.
var camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);
// create a render and set the size
var renderer = new THREE.WebGLRenderer();
// var renderer = new THREE.WebGLRenderer({alpha: true});
/**
* alpha: true 启用透明度支持
* !!!透明度没有生效
* 1.因为没有启用渲染器透明度支持
* 2.没有正确使用setClearColor方法两个参数
* renderer.setClearColor(new THREE.Color(0xEEEEEE, 1.0));
* 透明度 （0-1） 0 完全透明 1完全不透明
**/
renderer.setClearColor(new THREE.Color(0xEEEEEE, 1.0));
renderer.setSize(window.innerWidth, window.innerHeight);
// renderer.shadowMapEnabled = true;
// 启用阴影贴图：用于在3D场景中生成和渲染物体的阴影
// create the ground plane
var planeGeometry = new THREE.PlaneGeometry(60, 20, 20, 20);
var planeMaterial = new THREE.MeshPhongMaterial({ color: 0xffffff });
var plane = new THREE.Mesh(planeGeometry, planeMaterial);
plane.receiveShadow = true; // 接收阴影
// rotate and position the plane
plane.rotation.x = -0.5 * Math.PI;
plane.position.x = 15;
plane.position.y = 0;
plane.position.z = 0;
// add the plane to the scene
scene.add(plane);
// create a cube
var cubeGeometry = new THREE.BoxGeometry(4, 4, 4);
var cubeMaterial = new THREE.MeshLambertMaterial({ color: 0xff7777 });
// MeshLambertMaterial 基于Lambert反射模型的材质，适用于不发光且没有高光的物体（表面粗糙、没有明显反光）。它支持颜色、贴图、透明度等属性。
var cube = new THREE.Mesh(cubeGeometry, cubeMaterial);
cube.castShadow = true; // 投射阴影
// position the cube
cube.position.x = -4;
cube.position.y = 3;
cube.position.z = 0;
// add the cube to the scene
scene.add(cube);
var sphereGeometry = new THREE.SphereGeometry(4, 20, 20);
var sphereMaterial = new THREE.MeshLambertMaterial({ color: 0x7777ff });
var sphere = new THREE.Mesh(sphereGeometry, sphereMaterial);
// position the sphere
sphere.position.x = 20;
sphere.position.y = 0;
sphere.position.z = 2;
sphere.castShadow = true;
// add the sphere to the scene
scene.add(sphere);
// position and point the camera to the center of the scene
camera.position.x = -25;
camera.position.y = 30;
camera.position.z = 25;
camera.lookAt(new THREE.Vector3(10, 0, 0));
// 添加光源
// add subtle ambient lighting
var ambiColor = "#0c0c0c";
var ambientLight = new THREE.AmbientLight(ambiColor);
scene.add(ambientLight);
// add spotlight for the shadows
var spotLight = new THREE.SpotLight(0xffffff);
console.log(spotLight.position);
spotLight.position.set(-40, 60, -10);
spotLight.castShadow = true;
console.log(spotLight);
console.log(spotLight.target); // 默认（0,0,0）
console.log(spotLight.shadow); // undefined shadow属性是在r128之后引入的
// scene.add( spotLight );
var pointColor = "#ccffcc";
var pointLight = new THREE.PointLight(pointColor); // 无阴影
pointLight.distance = 100; // 0 无限远 光线强度不随距离增加而减弱
scene.add(pointLight);
// add a small sphere simulating the pointlight
var sphereLight = new THREE.SphereGeometry(0.2);
var sphereLightMaterial = new THREE.MeshBasicMaterial({ color: 0xac6c25 });
var sphereLightMesh = new THREE.Mesh(sphereLight, sphereLightMaterial);
sphereLightMesh.castShadow = true;
sphereLightMesh.position = new THREE.Vector3(3, 0, 3);
scene.add(sphereLightMesh);
// const directionalLight = new THREE.DirectionalLight(0xffffff, 1);
// directionalLight.position.set(-40, 60, -10);
// directionalLight.castShadow = true;
// scene.add(directionalLight);
// add the output of the renderer to the html element
document.getElementById("WebGL-output").appendChild(renderer.domElement);
// call the render function
var step = 0;
// used to determine the switch point for the light animation
var invert = 1;
var phase = 0;
var controls = new function () {
this.rotationSpeed = 0.03;
this.bouncingSpeed = 0.03;
this.ambientColor = ambiColor;
this.pointColor = pointColor;
this.intensity = 1;
this.distance = 100;
};
var gui = new dat.GUI();
gui.addColor(controls, 'ambientColor').onChange(function (e) {
ambientLight.color = new THREE.Color(e);
});
gui.addColor(controls, 'pointColor').onChange(function (e) {
pointLight.color = new THREE.Color(e);
});
gui.add(controls, 'intensity', 0, 3).onChange(function (e) {
pointLight.intensity = e;
});
gui.add(controls, 'distance', 0, 100).onChange(function (e) {
pointLight.distance = e;
});
var stats = initStats();
render();
function render() {
stats.update();
// rotate the cube around its axes
cube.rotation.x += controls.rotationSpeed;
cube.rotation.y += controls.rotationSpeed;
cube.rotation.z += controls.rotationSpeed;
// bounce the sphere up and down
step += controls.bouncingSpeed;
sphere.position.x = 20 + (10 * (Math.cos(step)));
sphere.position.y = 2 + (10 * Math.abs(Math.sin(step)));
// move the light simulation
if (phase > 2 * Math.PI) {
invert = invert * -1;
phase -= 2 * Math.PI;
} else {
phase += controls.rotationSpeed;
}
sphereLightMesh.position.z = +(7 * (Math.sin(phase)));
sphereLightMesh.position.x = +(14 * (Math.cos(phase)));
sphereLightMesh.position.y = 5;
if (invert < 0) {
var pivot = 14;
sphereLightMesh.position.x = (invert * (sphereLightMesh.position.x - pivot)) + pivot;
}
pointLight.position.copy(sphereLightMesh.position);
// render using requestAnimationFrame
requestAnimationFrame(render);
renderer.render(scene, camera);
}
function initStats() {
var stats = new Stats();
stats.setMode(0); // 0: fps, 1: ms
// Align top-left
stats.domElement.style.position = 'absolute';
stats.domElement.style.left = '0px';
stats.domElement.style.top = '0px';
document.getElementById("Stats-output").appendChild(stats.domElement);
return stats;
}
}
window.onload = init
</script>
</body>
</html>