examples/webgl_lights_spotlights.html

<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js webgl - lights - spot light</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<link type="text/css" rel="stylesheet" href="main.css">
	</head>
	<body>

		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - SpotLights<br/>
			by <a href="http://master-domain.com" target="_blank" rel="noopener">Master James</a>
		</div>

		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">
			import * as THREE from 'three';
			import TWEEN from 'three/addons/libs/tween.module.js';
			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';

			const renderer = new THREE.WebGLRenderer( { antialias: true } );
			renderer.setPixelRatio( window.devicePixelRatio );
			renderer.setSize( window.innerWidth, window.innerHeight );
			renderer.setAnimationLoop( animate );

			const camera = new THREE.PerspectiveCamera( 35, window.innerWidth / window.innerHeight, 0.1, 100 );

			const controls = new OrbitControls( camera, renderer.domElement );

			const scene = new THREE.Scene();

			const matFloor = new THREE.MeshPhongMaterial( { color: 0x808080 } );
			const matBox = new THREE.MeshPhongMaterial( { color: 0xaaaaaa } );

			const geoFloor = new THREE.PlaneGeometry( 100, 100 );
			const geoBox = new THREE.BoxGeometry( 0.3, 0.1, 0.2 );

			const mshFloor = new THREE.Mesh( geoFloor, matFloor );
			mshFloor.rotation.x = - Math.PI * 0.5;
			const mshBox = new THREE.Mesh( geoBox, matBox );

			const ambient = new THREE.AmbientLight( 0x444444 );

			const spotLight1 = createSpotlight( 0xFF7F00 );
			const spotLight2 = createSpotlight( 0x00FF7F );
			const spotLight3 = createSpotlight( 0x7F00FF );

			let lightHelper1, lightHelper2, lightHelper3;

			function init() {

				renderer.shadowMap.enabled = true;
				renderer.shadowMap.type = THREE.PCFSoftShadowMap;

				camera.position.set( 4.6, 2.2, - 2.1 );

				spotLight1.position.set( 1.5, 4, 4.5 );
				spotLight2.position.set( 0, 4, 3.5 );
				spotLight3.position.set( - 1.5, 4, 4.5 );

				lightHelper1 = new THREE.SpotLightHelper( spotLight1 );
				lightHelper2 = new THREE.SpotLightHelper( spotLight2 );
				lightHelper3 = new THREE.SpotLightHelper( spotLight3 );

				mshFloor.receiveShadow = true;
				mshFloor.position.set( 0, - 0.05, 0 );

				mshBox.castShadow = true;
				mshBox.receiveShadow = true;
				mshBox.position.set( 0, 0.5, 0 );

				scene.add( mshFloor );
				scene.add( mshBox );
				scene.add( ambient );
				scene.add( spotLight1, spotLight2, spotLight3 );
				scene.add( lightHelper1, lightHelper2, lightHelper3 );

				document.body.appendChild( renderer.domElement );
				window.addEventListener( 'resize', onWindowResize );

				controls.target.set( 0, 0.5, 0 );
				controls.maxPolarAngle = Math.PI / 2;
				controls.minDistance = 1;
				controls.maxDistance = 10;
				controls.update();

			}

			function createSpotlight( color ) {

				const newObj = new THREE.SpotLight( color, 10 );

				newObj.castShadow = true;
				newObj.angle = 0.3;
				newObj.penumbra = 0.2;
				newObj.decay = 2;
				newObj.distance = 50;

				return newObj;

			}

			function onWindowResize() {

				camera.aspect = window.innerWidth / window.innerHeight;
				camera.updateProjectionMatrix();
				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function tween( light ) {

				new TWEEN.Tween( light ).to( {
					angle: ( Math.random() * 0.7 ) + 0.1,
					penumbra: Math.random() + 1
				}, Math.random() * 3000 + 2000 )
					.easing( TWEEN.Easing.Quadratic.Out ).start();

				new TWEEN.Tween( light.position ).to( {
					x: ( Math.random() * 3 ) - 1.5,
					y: ( Math.random() * 1 ) + 1.5,
					z: ( Math.random() * 3 ) - 1.5
				}, Math.random() * 3000 + 2000 )
					.easing( TWEEN.Easing.Quadratic.Out ).start();

			}

			function updateTweens() {

				tween( spotLight1 );
				tween( spotLight2 );
				tween( spotLight3 );

				setTimeout( updateTweens, 5000 );

			}

			function animate() {

				TWEEN.update();

				if ( lightHelper1 ) lightHelper1.update();
				if ( lightHelper2 ) lightHelper2.update();
				if ( lightHelper3 ) lightHelper3.update();

				renderer.render( scene, camera );

			}

			init();
			updateTweens();

		</script>
	</body>
</html>