examples/webgl_decals.html

<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js webgl - decal splatter</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">three.js</a> - decal splatter<br/>
			click to shoot
		</div>

		<script type="module">

			import * as THREE from '../build/three.module.js';

			import Stats from './jsm/libs/stats.module.js';
			import { GUI } from './jsm/libs/dat.gui.module.js';

			import { OrbitControls } from './jsm/controls/OrbitControls.js';
			import { GLTFLoader } from './jsm/loaders/GLTFLoader.js';
			import { DecalGeometry } from './jsm/geometries/DecalGeometry.js';

			var container = document.getElementById( 'container' );

			var renderer, scene, camera, stats;
			var mesh;
			var raycaster;
			var line;

			var intersection = {
				intersects: false,
				point: new THREE.Vector3(),
				normal: new THREE.Vector3()
			};
			var mouse = new THREE.Vector2();

			var textureLoader = new THREE.TextureLoader();
			var decalDiffuse = textureLoader.load( 'textures/decal/decal-diffuse.png' );
			var decalNormal = textureLoader.load( 'textures/decal/decal-normal.jpg' );

			var decalMaterial = new THREE.MeshPhongMaterial( {
				specular: 0x444444,
				map: decalDiffuse,
				normalMap: decalNormal,
				normalScale: new THREE.Vector2( 1, 1 ),
				shininess: 30,
				transparent: true,
				depthTest: true,
				depthWrite: false,
				polygonOffset: true,
				polygonOffsetFactor: - 4,
				wireframe: false
			} );

			var decals = [];
			var mouseHelper;
			var position = new THREE.Vector3();
			var orientation = new THREE.Euler();
			var size = new THREE.Vector3( 10, 10, 10 );

			var params = {
				minScale: 10,
				maxScale: 20,
				rotate: true,
				clear: function () {

					removeDecals();

				}
			};

			window.addEventListener( 'load', init );

			function init() {

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

				stats = new Stats();
				container.appendChild( stats.dom );

				scene = new THREE.Scene();

				camera = new THREE.PerspectiveCamera( 45, window.innerWidth / window.innerHeight, 1, 1000 );
				camera.position.z = 120;
				camera.target = new THREE.Vector3();

				var controls = new OrbitControls( camera, renderer.domElement );
				controls.minDistance = 50;
				controls.maxDistance = 200;

				scene.add( new THREE.AmbientLight( 0x443333 ) );

				var light = new THREE.DirectionalLight( 0xffddcc, 1 );
				light.position.set( 1, 0.75, 0.5 );
				scene.add( light );

				var light = new THREE.DirectionalLight( 0xccccff, 1 );
				light.position.set( - 1, 0.75, - 0.5 );
				scene.add( light );

				var geometry = new THREE.BufferGeometry();
				geometry.setFromPoints( [ new THREE.Vector3(), new THREE.Vector3() ] );

				line = new THREE.Line( geometry, new THREE.LineBasicMaterial() );
				scene.add( line );

				loadLeePerrySmith();

				raycaster = new THREE.Raycaster();

				mouseHelper = new THREE.Mesh( new THREE.BoxBufferGeometry( 1, 1, 10 ), new THREE.MeshNormalMaterial() );
				mouseHelper.visible = false;
				scene.add( mouseHelper );

				window.addEventListener( 'resize', onWindowResize, false );

				var moved = false;

				controls.addEventListener( 'change', function () {

					moved = true;

				} );

				window.addEventListener( 'mousedown', function () {

					moved = false;

				}, false );

				window.addEventListener( 'mouseup', function () {

					checkIntersection();
					if ( ! moved && intersection.intersects ) shoot();

				} );

				window.addEventListener( 'mousemove', onTouchMove );
				window.addEventListener( 'touchmove', onTouchMove );

				function onTouchMove( event ) {

					var x, y;

					if ( event.changedTouches ) {

						x = event.changedTouches[ 0 ].pageX;
						y = event.changedTouches[ 0 ].pageY;

					} else {

						x = event.clientX;
						y = event.clientY;

					}

					mouse.x = ( x / window.innerWidth ) * 2 - 1;
					mouse.y = - ( y / window.innerHeight ) * 2 + 1;

					checkIntersection();

				}

				function checkIntersection() {

					if ( ! mesh ) return;

					raycaster.setFromCamera( mouse, camera );

					var intersects = raycaster.intersectObjects( [ mesh ] );

					if ( intersects.length > 0 ) {

						var p = intersects[ 0 ].point;
						mouseHelper.position.copy( p );
						intersection.point.copy( p );

						var n = intersects[ 0 ].face.normal.clone();
						n.transformDirection( mesh.matrixWorld );
						n.multiplyScalar( 10 );
						n.add( intersects[ 0 ].point );

						intersection.normal.copy( intersects[ 0 ].face.normal );
						mouseHelper.lookAt( n );

						var positions = line.geometry.attributes.position;
						positions.setXYZ( 0, p.x, p.y, p.z );
						positions.setXYZ( 1, n.x, n.y, n.z );
						positions.needsUpdate = true;

						intersection.intersects = true;

					} else {

						intersection.intersects = false;

					}

				}

				var gui = new GUI();

				gui.add( params, 'minScale', 1, 30 );
				gui.add( params, 'maxScale', 1, 30 );
				gui.add( params, 'rotate' );
				gui.add( params, 'clear' );
				gui.open();

				onWindowResize();
				animate();

			}

			function loadLeePerrySmith() {

				var loader = new GLTFLoader();

				loader.load( 'models/gltf/LeePerrySmith/LeePerrySmith.glb', function ( gltf ) {

					mesh = gltf.scene.children[ 0 ];
					mesh.material = new THREE.MeshPhongMaterial( {
						specular: 0x111111,
						map: textureLoader.load( 'models/gltf/LeePerrySmith/Map-COL.jpg' ),
						specularMap: textureLoader.load( 'models/gltf/LeePerrySmith/Map-SPEC.jpg' ),
						normalMap: textureLoader.load( 'models/gltf/LeePerrySmith/Infinite-Level_02_Tangent_SmoothUV.jpg' ),
						shininess: 25
					} );

					scene.add( mesh );
					mesh.scale.set( 10, 10, 10 );

				} );

			}

			function shoot() {

				position.copy( intersection.point );
				orientation.copy( mouseHelper.rotation );

				if ( params.rotate ) orientation.z = Math.random() * 2 * Math.PI;

				var scale = params.minScale + Math.random() * ( params.maxScale - params.minScale );
				size.set( scale, scale, scale );

				var material = decalMaterial.clone();
				material.color.setHex( Math.random() * 0xffffff );

				var m = new THREE.Mesh( new DecalGeometry( mesh, position, orientation, size ), material );

				decals.push( m );
				scene.add( m );

			}

			function removeDecals() {

				decals.forEach( function ( d ) {

					scene.remove( d );

				} );

				decals = [];

			}

			function onWindowResize() {

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

				renderer.setSize( window.innerWidth, window.innerHeight );

			}

			function animate() {

				requestAnimationFrame( animate );

				renderer.render( scene, camera );

				stats.update();

			}

		</script>

	</body>
</html>