examples/webgl_modifier_edgesplit.html

<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js webgl - modifier - Edge Split modifier</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>
		<script type="importmap">
			{
				"imports": {
					"three": "../build/three.module.js",
					"three/addons/": "./jsm/"
				}
			}
		</script>

		<script type="module">

			import * as THREE from 'three';

			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
			import { OBJLoader } from 'three/addons/loaders/OBJLoader.js';
			import { EdgeSplitModifier } from 'three/addons/modifiers/EdgeSplitModifier.js';
			import * as BufferGeometryUtils from 'three/addons/utils/BufferGeometryUtils.js';

			import { GUI } from 'three/addons/libs/lil-gui.module.min.js';

			let renderer, scene, camera;
			let modifier, mesh, baseGeometry;
			let map;

			const params = {
				smoothShading: true,
				edgeSplit: true,
				cutOffAngle: 20,
				showMap: false,
				tryKeepNormals: true,
			};

			init();

			function init() {

				const info = document.createElement( 'div' );
				info.style.position = 'absolute';
				info.style.top = '10px';
				info.style.width = '100%';
				info.style.textAlign = 'center';
				info.innerHTML = '<a href="https://threejs.org" target="_blank" rel="noopener">three.js</a> - Edge Split modifier';
				document.body.appendChild( info );

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

				scene = new THREE.Scene();

				camera = new THREE.PerspectiveCamera( 75, window.innerWidth / window.innerHeight );

				const controls = new OrbitControls( camera, renderer.domElement );
				controls.addEventListener( 'change', render ); // use if there is no animation loop
				controls.enableDamping = true;
				controls.dampingFactor = 0.25;
				controls.rotateSpeed = 0.35;
				controls.minZoom = 1;
				camera.position.set( 0, 0, 4 );

				scene.add( new THREE.HemisphereLight( 0xffffff, 0x444444, 3 ) );

				new OBJLoader().load(
					'./models/obj/cerberus/Cerberus.obj',
					function ( group ) {

						const cerberus = group.children[ 0 ];
						const modelGeometry = cerberus.geometry;

						modifier = new EdgeSplitModifier();
						baseGeometry = BufferGeometryUtils.mergeVertices( modelGeometry );

						mesh = new THREE.Mesh( getGeometry(), new THREE.MeshStandardMaterial() );
						mesh.material.flatShading = ! params.smoothShading;
						mesh.rotateY( - Math.PI / 2 );
						mesh.scale.set( 3.5, 3.5, 3.5 );
						mesh.translateZ( 1.5 );
						scene.add( mesh );

						if ( map !== undefined && params.showMap ) {

							mesh.material.map = map;
							mesh.material.needsUpdate = true;

						}

						render();

					}
				);

				window.addEventListener( 'resize', onWindowResize );

				new THREE.TextureLoader().load( './models/obj/cerberus/Cerberus_A.jpg', function ( texture ) {

					map = texture;
					map.colorSpace = THREE.SRGBColorSpace;

					if ( mesh !== undefined && params.showMap ) {

						mesh.material.map = map;
						mesh.material.needsUpdate = true;

					}

				} );


				const gui = new GUI( { title: 'Edge split modifier parameters' } );

				gui.add( params, 'showMap' ).onFinishChange( updateMesh );
				gui.add( params, 'smoothShading' ).onFinishChange( updateMesh );
				gui.add( params, 'edgeSplit' ).onFinishChange( updateMesh );
				gui.add( params, 'cutOffAngle' ).min( 0 ).max( 180 ).onFinishChange( updateMesh );
				gui.add( params, 'tryKeepNormals' ).onFinishChange( updateMesh );

			}

			function onWindowResize() {

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

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

				render();

			}


			function getGeometry() {

				let geometry;

				if ( params.edgeSplit ) {

					geometry = modifier.modify(
						baseGeometry,
						params.cutOffAngle * Math.PI / 180,
						params.tryKeepNormals
					);

				} else {

					geometry = baseGeometry;

				}

				return geometry;

			}


			function updateMesh() {

				if ( mesh !== undefined ) {

					mesh.geometry = getGeometry();

					let needsUpdate = mesh.material.flatShading === params.smoothShading;
					mesh.material.flatShading = params.smoothShading === false;

					if ( map !== undefined ) {

						needsUpdate = needsUpdate || mesh.material.map !== ( params.showMap ? map : null );
						mesh.material.map = params.showMap ? map : null;

					}

					mesh.material.needsUpdate = needsUpdate;

					render();

				}

			}


			function render() {

				renderer.render( scene, camera );

			}

		</script>

	</body>
</html>