29 Three.js的特殊光源THREE.RectAreaLight窗口射入光线模拟
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2022-05-23 13:29:17
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简介
这种光在整个面上均匀地发射出一个矩形平面。这可以用来模拟像明亮的窗户或带状照明的东西。
案例查看地址：http://www.wjceo.com/blog/threejs/2018-02-12/31.html
简单创建
由于是特殊光源，而且比较复杂，所以此灯光需要额外引入插件来创建
<script src="examples/js/lights/RectAreaLightUniformsLib.js"></script>然后就可以实例化了
var rectLight = new THREE.RectAreaLight(颜色, 光的强度, 宽度, 高度);最后添加到场景当中即可
案例代码
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style type="text/css">
html, body {
margin: 0;
height: 100%;
}
canvas {
display: block;
}
</style>
</head>
<body onload="draw();">
</body>
<script src="build/three.js"></script>
<script src="examples/js/lights/RectAreaLightUniformsLib.js"></script>
<script src="examples/js/controls/OrbitControls.js"></script>
<script src="examples/js/libs/stats.min.js"></script>
<script src="examples/js/libs/dat.gui.min.js"></script>
<script>
var renderer;
function initRender() {
renderer = new THREE.WebGLRenderer({antialias: true});
renderer.setSize(window.innerWidth, window.innerHeight);
//告诉渲染器需要阴影效果
renderer.shadowMap.enabled = true;
renderer.shadowMap.type = THREE.PCFSoftShadowMap; // 默认的是，没有设置的这个清晰 THREE.PCFShadowMap
//renderer.gammaInput = true;
//renderer.gammaOutput = true;
document.body.appendChild(renderer.domElement);
}
var camera;
function initCamera() {
camera = new THREE.PerspectiveCamera(45, window.innerWidth / window.innerHeight, 0.1, 1000);
camera.position.set(0, 40, 100);
camera.lookAt(new THREE.Vector3(0, 0, 0));
}
var scene;
function initScene() {
scene = new THREE.Scene();
}
var rectLight,rectLightHelper;
function initLight() {
var ambientLight = new THREE.AmbientLight(0x111111);
scene.add(ambientLight);
rectLight = new THREE.RectAreaLight(0xffffff, 500, 10, 10);
rectLight.position.set(5, 10, -20);
scene.add(rectLight);
// TODO: ensure RectAreaLight handles target param correctly
rectLightHelper = new THREE.RectAreaLightHelper(rectLight);
scene.add(rectLightHelper);
}
var cube,plane;
function initModel() {
//辅助工具
var helper = new THREE.AxisHelper(10);
scene.add(helper);
//球体
var sphereGeometry = new THREE.SphereGeometry(10,30,30);
var sphereMaterial = new THREE.MeshStandardMaterial({color:0xff00ff});
var sphere = new THREE.Mesh(sphereGeometry,sphereMaterial);
sphere.position.set(-20,20,0);
sphere.castShadow = true;
scene.add(sphere);
//立方体
var cubeGeometry = new THREE.CubeGeometry(10,10,10);
var cubeMaterial = new THREE.MeshLambertMaterial({color: 0x00ffff});
cube = new THREE.Mesh(cubeGeometry, cubeMaterial);
cube.position.x = 30;
cube.position.y = 5;
cube.position.z = -5;
//告诉立方体需要投射阴影
cube.castShadow = true;
scene.add(cube);
//底部平面
var planeGeometry = new THREE.PlaneGeometry(5000, 5000, 20, 20);
var planeMaterial = new THREE.MeshStandardMaterial({color: 0xaaaaaa});
plane = new THREE.Mesh(planeGeometry, planeMaterial);
plane.rotation.x = -0.5 * Math.PI;
plane.position.y = -0;
//告诉底部平面需要接收阴影
plane.receiveShadow = true;
scene.add(plane);
}
//初始化性能插件
var stats;
function initStats() {
stats = new Stats();
document.body.appendChild(stats.dom);
}
//用户交互插件 鼠标左键按住旋转，右键按住平移，滚轮缩放
var controls;
function initControls() {
controls = new THREE.OrbitControls(camera, renderer.domElement);
// 如果使用animate方法时，将此函数删除
//controls.addEventListener( 'change', render );
// 使动画循环使用时阻尼或自转 意思是否有惯性
controls.enableDamping = true;
//动态阻尼系数 就是鼠标拖拽旋转灵敏度
//controls.dampingFactor = 0.25;
//是否可以缩放
controls.enableZoom = true;
//是否自动旋转
controls.autoRotate = false;
//设置相机距离原点的最远距离
controls.minDistance = 50;
//设置相机距离原点的最远距离
controls.maxDistance = 200;
//是否开启右键拖拽
controls.enablePan = true;
//设置从上面到下面的可旋转角度
controls.maxPolarAngle = Math.PI*4.5/10;
//设置从下面到上面的可旋转角度
//controls.minPolarAngle = Math.PI/2;
}
//初始化dat.GUI简化试验流程
var param;
function initGui() {
//声明一个保存需求修改的相关数据的对象
param = {
motion: true,
width: rectLight.width,
height: rectLight.height,
color: rectLight.color.getHex(),
intensity: rectLight.intensity
};
var datGui = new dat.GUI();
//将设置属性添加到gui当中，gui.add(对象，属性，最小值，最大值）
//var lightFolder = gui.addFolder('Light');
datGui.add(param, 'width', 0.1, 100).onChange(function (val) {
rectLight.width = val;
});
datGui.add(param, 'height', 0.1, 100).onChange(function (val) {
rectLight.height = val;
});
datGui.addColor(param, 'color').onChange(function (val) {
rectLight.color.setHex(val);
});
datGui.add(param, 'intensity', 0.0, 1000).onChange(function (val) {
rectLight.intensity = val;
});
datGui.open();
}
function render() {
rectLightHelper.update();
renderer.render(scene, camera);
}
//窗口变动触发的函数
function onWindowResize() {
camera.aspect = window.innerWidth / window.innerHeight;
camera.updateProjectionMatrix();
render();
renderer.setSize(window.innerWidth, window.innerHeight);
}
function animate() {
//更新控制器
render();
//更新性能插件
stats.update();
controls.update();
requestAnimationFrame(animate);
}
function draw() {
initRender();
initScene();
initCamera();
initLight();
initModel();
initControls();
initStats();
initGui();
animate();
window.onresize = onWindowResize;
}
</script>
</html>