examples/webgl_water_flowmap.html

<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js - water flow map</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="container"></div>
		<div id="info">
			<a href="https://threejs.org" target="_blank" rel="noopener noreferrer">three.js</a> - water flow map
		</div>

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

		<script type="module">

			import * as THREE from 'three';

			import { GUI } from 'three/addons/libs/lil-gui.module.min.js';
			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
			import { Water } from 'three/addons/objects/Water2.js';

			let scene, camera, renderer, water;

			init();

			function init() {

				// scene

				scene = new THREE.Scene();

				// camera

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 0.1, 200 );
				camera.position.set( 0, 25, 0 );
				camera.lookAt( scene.position );

				// ground

				const groundGeometry = new THREE.PlaneGeometry( 20, 20, 10, 10 );
				const groundMaterial = new THREE.MeshBasicMaterial( { color: 0xe7e7e7 } );
				const ground = new THREE.Mesh( groundGeometry, groundMaterial );
				ground.rotation.x = Math.PI * - 0.5;
				scene.add( ground );

				const textureLoader = new THREE.TextureLoader();
				textureLoader.load( 'textures/floors/FloorsCheckerboard_S_Diffuse.jpg', function ( map ) {

					map.wrapS = THREE.RepeatWrapping;
					map.wrapT = THREE.RepeatWrapping;
					map.anisotropy = 16;
					map.repeat.set( 4, 4 );
					map.colorSpace = THREE.SRGBColorSpace;
					groundMaterial.map = map;
					groundMaterial.needsUpdate = true;

				} );

				// water

				const waterGeometry = new THREE.PlaneGeometry( 20, 20 );
				const flowMap = textureLoader.load( 'textures/water/Water_1_M_Flow.jpg' );

				water = new Water( waterGeometry, {
					scale: 2,
					textureWidth: 1024,
					textureHeight: 1024,
					flowMap: flowMap
				} );

				water.position.y = 1;
				water.rotation.x = Math.PI * - 0.5;
				scene.add( water );

				// flow map helper

				const helperGeometry = new THREE.PlaneGeometry( 20, 20 );
				const helperMaterial = new THREE.MeshBasicMaterial( { map: flowMap } );
				const helper = new THREE.Mesh( helperGeometry, helperMaterial );
				helper.position.y = 1.01;
				helper.rotation.x = Math.PI * - 0.5;
				helper.visible = false;
				scene.add( helper );

				// renderer

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

				//

				const gui = new GUI();
				gui.add( helper, 'visible' ).name( 'Show Flow Map' );
				gui.open();

				//

				const controls = new OrbitControls( camera, renderer.domElement );
				controls.minDistance = 5;
				controls.maxDistance = 50;

				//

				window.addEventListener( 'resize', onWindowResize );

			}

			function onWindowResize() {

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

			}

			function animate() {

				renderer.render( scene, camera );

			}

		</script>

</body>
</html>