mrdoob · sunag · Jun 1, 2025 · May 31, 2025 · Jun 1, 2025 · Jun 1, 2025
diff --git a/examples/files.json b/examples/files.json
@@ -329,6 +329,7 @@
 		"webgpu_display_stereo",
 		"webgpu_equirectangular",
 		"webgpu_instance_mesh",
+		"webgpu_instance_path",
 		"webgpu_instance_points",
 		"webgpu_instance_sprites",
 		"webgpu_instance_uniform",

diff --git a/examples/screenshots/webgpu_instance_path.jpg b/examples/screenshots/webgpu_instance_path.jpg
diff --git a/examples/webgpu_instance_path.html b/examples/webgpu_instance_path.html
@@ -0,0 +1,171 @@
+<!DOCTYPE html>
+<html lang="en">
+	<head>
+		<title>three.js webgpu - geometry path</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> webgpu - geometry path
+		</div>
+
+		<script type="importmap">
+			{
+				"imports": {
+					"three": "../build/three.webgpu.js",
+					"three/webgpu": "../build/three.webgpu.js",
+					"three/tsl": "../build/three.tsl.js",
+					"three/addons/": "./jsm/"
+				}
+			}
+		</script>
+
+		<script type="module">
+
+			import * as THREE from 'three';
+
+			import { OrbitControls } from 'three/addons/controls/OrbitControls.js';
+			import { RoomEnvironment } from 'three/addons/environments/RoomEnvironment.js';
+
+			import { abs, add, instancedBufferAttribute, positionLocal, mod, time, sin, vec3, select, float, screenUV, color } from 'three/tsl';
+
+			let camera, scene, renderer, controls;
+
+			const count = 1000;
+
+			init();
+
+			async function init() {
+
+				camera = new THREE.PerspectiveCamera( 60, window.innerWidth / window.innerHeight, 0.01, 100 );
+				camera.position.z = 15;
+
+				scene = new THREE.Scene();
+				scene.backgroundNode = screenUV.distance( .5 ).remap( 0, 0.65 ).mix( color( 0x94254c ), color( 0x000000 ) );
+
+				// generate a path representing a heart shape
+
+				const x = 0, y = 0;
+
+				const path = new THREE.Path()
+					.moveTo( x - 2.5, y - 2.5 )
+					.bezierCurveTo( x - 2.5, y - 2.5, x - 2, y, x, y )
+					.bezierCurveTo( x + 3, y, x + 3, y - 3.5, x + 3, y - 3.5 )
+					.bezierCurveTo( x + 3, y - 5.5, x + 1, y - 7.7, x - 2.5, y - 9.5 )
+					.bezierCurveTo( x - 6, y - 7.7, x - 8, y - 5.5, x - 8, y - 3.5 )
+					.bezierCurveTo( x - 8, y - 3.5, x - 8, y, x - 5, y )
+					.bezierCurveTo( x - 3.5, y, x - 2.5, y - 2.5, x - 2.5, y - 2.5 );
+
+				// generate instanced ico-spheres along the path
+
+				const geometry = new THREE.IcosahedronGeometry( 0.1 );
+				const material = new THREE.MeshStandardNodeMaterial();
+
+				const mesh = new THREE.Mesh( geometry, material );
+				mesh.position.set( 2.5, 5, 0 );
+				mesh.count = count;
+				mesh.frustumCulled = false;
+
+				scene.add( mesh );
+
+				// instance data
+
+				const v = new THREE.Vector3();
+				const c = new THREE.Color();
+
+				const positions = [];
+				const times = [];
+				const seeds = [];
+				const colors = [];
+
+				for ( let i = 0; i < count; i ++ ) {
+
+					const t = i / count;
+					path.getPointAt( t, v );
+
+					v.x += ( 0.5 - Math.random() );
+					v.y += ( 0.5 - Math.random() );
+					v.z = ( 0.5 - Math.random() );
+
+					positions.push( v.x, v.y, v.z );
+					times.push( t );
+					seeds.push( Math.random() );
+
+					c.setHSL( 0.75 + ( Math.random() * 0.25 ), 1, 0.4 );
+
+					colors.push( c.r, c.g, c.b );
+
+				}
+
+				const positionAttribute = new THREE.InstancedBufferAttribute( new Float32Array( positions ), 3 );
+				const colorAttribute = new THREE.InstancedBufferAttribute( new Float32Array( colors ), 3 );
+				const timeAttribute = new THREE.InstancedBufferAttribute( new Float32Array( times ), 1 );
+				const seedAttribute = new THREE.InstancedBufferAttribute( new Float32Array( seeds ), 1 );
+
+				// TSL
+
+				const instancePosition = instancedBufferAttribute( positionAttribute );
+				const instanceColor = instancedBufferAttribute( colorAttribute );
+				const instanceSeed = instancedBufferAttribute( seedAttribute );
+				const instanceTime = instancedBufferAttribute( timeAttribute );
+
+				const localTime = instanceTime.add( time );
+				const modTime = mod( time.mul( 0.4 ), 1 );
+
+				const s0 = sin( localTime.add( instanceSeed ) ).mul( 0.25 );
+
+				const dist = abs( instanceTime.sub( modTime ) ).toConst(); // modTime and instanceTime are in the range [0,1]
+				const wrapDist = select( dist.greaterThan( 0.5 ), dist.oneMinus(), dist ).toConst(); // the normalized distance should wrap around 0/1
+				const s1 = select( wrapDist.greaterThan( 0.1 ), float( 1 ), wrapDist.remap( 0, 0.1, 3, 1 ) ); // compute a scale in a range around the current interpolated value
+
+				const offset = vec3( instancePosition.x, instancePosition.y.add( s0 ), instancePosition.z ).toConst( 'offset' );
+				material.positionNode = add( positionLocal.mul( s1 ), offset );
+				material.colorNode = instanceColor;
+
+				//
+
+				renderer = new THREE.WebGPURenderer( { antialias: true } );
+				renderer.setPixelRatio( window.devicePixelRatio );
+				renderer.setSize( window.innerWidth, window.innerHeight );
+				renderer.setAnimationLoop( animate );
+				renderer.toneMapping = THREE.NeutralToneMapping;
+				document.body.appendChild( renderer.domElement );
+
+				await renderer.init();
+
+				const pmremGenerator = new THREE.PMREMGenerator( renderer );
+				scene.environment = pmremGenerator.fromScene( new RoomEnvironment(), 0.04 ).texture;
+
+				controls = new OrbitControls( camera, renderer.domElement );
+				controls.enableDamping = true;
+
+				//
+
+				window.addEventListener( 'resize', onWindowResize );
+
+			}
+
+			function onWindowResize() {
+
+				camera.aspect = window.innerWidth / window.innerHeight;
+				camera.updateProjectionMatrix();
+
+				renderer.setSize( window.innerWidth, window.innerHeight );
+
+			}
+
+			function animate() {
+
+				controls.update();
+
+				renderer.render( scene, camera );
+
+			}
+
+		</script>
+
+	</body>
+</html>