samien
/
three.js
mirror of https://github.com/mrdoob/three.js.git


			
				
					
						
						
							123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376
							<!DOCTYPE html>
<html lang="en">
	<head>
		<title>three.js webgpu - city generator</title>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
		<meta property="og:title" content="three.js webgpu - city generator">
		<meta property="og:type" content="website">
		<meta property="og:url" content="https://threejs.org/examples/webgpu_generator_city.html">
		<meta property="og:image" content="https://threejs.org/examples/screenshots/webgpu_generator_city.jpg">
		<link type="text/css" rel="stylesheet" href="example.css">
	</head>
	<body>

		<div id="info">
			<a href="https://threejs.org/" target="_blank" rel="noopener" class="logo-link"></a>

			<div class="title-wrapper">
				<a href="https://threejs.org/" target="_blank" rel="noopener">three.js</a><span>City Generator</span>
			</div>

			<small>
				A few procedurally generated city blocks of Neo-Gothic terracotta skyscrapers.<br />
				Use WASD to move around.
			</small>
		</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/webgpu';
			import { pass } from 'three/tsl';

			import { Inspector } from 'three/addons/inspector/Inspector.js';
			import { FirstPersonControls } from 'three/addons/controls/FirstPersonControls.js';
			import { SkyMesh } from 'three/addons/objects/SkyMesh.js';
			import { bloom } from 'three/addons/tsl/display/BloomNode.js';
			import { CityGenerator, createBuildingMaterial, createRoadMaterial } from 'three/addons/generators/CityGenerator.js';
			import { LightProbeGrid } from 'three/addons/lighting/LightProbeGrid.js';
			import { LightProbeGridHelper } from 'three/addons/helpers/LightProbeGridHelper.js';

			let camera, scene, renderer, controls, timer;
			let cityGroup, cityProxy, materials, city, renderPipeline;
			let sky, sun, sunLight, pmremGenerator, envScene, envRenderTarget, cityBounds;
			let probes, probesHelper, rebakeTimer = null;

			// the irradiance grid spans the whole footprint plus the streets, rising to
			// the mid-rise rooftops. diffuse GI is low frequency, so a coarse grid still
			// reads the urban canyon: streets sit in shade, walls glow with terracotta bounce

			const GRID_SIZE = new THREE.Vector3( 240, 120, 170 );
			const GRID_PROBES = new THREE.Vector3( 10, 7, 8 );

			const parameters = {
				seed: 94,
				timeOfDay: 6.4, // hours: 6 sunrise, 12 noon, 18 sunset
				gi: true,
				showProbes: false
			};

			init();

			async function init() {

				renderer = new THREE.WebGPURenderer( { antialias: true } );
				renderer.setPixelRatio( window.devicePixelRatio );
				renderer.setSize( window.innerWidth, window.innerHeight );
				renderer.setAnimationLoop( animate );
				renderer.toneMapping = THREE.ACESFilmicToneMapping;
				renderer.toneMappingExposure = 0.13;
				renderer.shadowMap.enabled = true;
				renderer.inspector = new Inspector();
				document.body.appendChild( renderer.domElement );

				await renderer.init();

				pmremGenerator = new THREE.PMREMGenerator( renderer );

				scene = new THREE.Scene();
				scene.environmentIntensity = 0.05; // a hint of sky in the reflections; the diffuse sky fill comes occlusion-aware from the probe grid

				// a physical sky drives both the backdrop and the image-based
				// lighting; the time-of-day slider walks the sun along its arc

				sky = new SkyMesh();
				sky.scale.setScalar( 10000 );
				sky.turbidity.value = 8;
				sky.rayleigh.value = 3;
				sky.mieCoefficient.value = 0.008;
				sky.mieDirectionalG.value = 0.88;

				sun = new THREE.Vector3();
				envScene = new THREE.Scene();

				camera = new THREE.PerspectiveCamera( 55, window.innerWidth / window.innerHeight, 1, 20000 );
				camera.position.set( - 35, 55, - 100 );

				controls = new FirstPersonControls( camera, renderer.domElement );
				controls.movementSpeed = 15;
				controls.lookSpeed = 0.25;
				controls.lookAt( 35, 55, 0 );

				timer = new THREE.Timer();

				city = new CityGenerator( { seed: parameters.seed } );

				// road: wet asphalt with sidewalks, lane lines and crosswalks, all
				// aligned to the city grid via TSL. sized to the city footprint plus
				// one street ( a crosswalk's width ) of margin all round

				const floorW = city.layout.cityW + 2 * city.layout.street;
				const floorD = city.layout.cityD + 2 * city.layout.street;
				const ground = new THREE.Mesh( new THREE.PlaneGeometry( floorW, floorD ).rotateX( - Math.PI / 2 ), createRoadMaterial( city.layout ) );
				ground.receiveShadow = true;
				scene.add( ground );

				// everything a shadow can touch fits this box: the ground plane up to just
				// above the tallest tower crown. updateSun() wraps the shadow camera around it

				cityBounds = new THREE.Box3(
					new THREE.Vector3( - floorW / 2, 0, - floorD / 2 ),
					new THREE.Vector3( floorW / 2, 160, floorD / 2 )
				);

				// a single directional key aligned with the sky's sun, for the crisp
				// relief shadows the IBL alone can't give. its colour, intensity and
				// position — and the baked environment — are set by updateSun()

				sunLight = new THREE.DirectionalLight();
				sunLight.castShadow = true;
				sunLight.shadow.mapSize.set( 4096, 4096 );

				// acne is suppressed along the surface normal ( in world units ) rather
				// than with a depth bias: a depth bias scales with the shadow range, and
				// even a small one erases short casters, like the shadow beneath a car

				sunLight.shadow.normalBias = 0.05;
				scene.add( sunLight );

				updateSun();

				materials = { building: createBuildingMaterial( city.layout, parameters.seed ) };
				generateCity();

				// bake the irradiance grid once the city and sun are in place

				bakeProbes();

				renderPipeline = new THREE.RenderPipeline( renderer );

				const scenePass = pass( scene, camera );
				const scenePassColor = scenePass.getTextureNode();

				// bloom: a soft glow on the brightest areas, at quarter-res since the
				// result is heavily blurred anyway

				const bloomPass = bloom( scenePassColor, 0.05, 0.0, 0.0 );
				bloomPass.setResolutionScale( 0.25 );

				renderPipeline.outputNode = scenePassColor.add( bloomPass );

				// parameters

				const gui = renderer.inspector.createParameters( 'City' );
				gui.add( parameters, 'seed', 0, 100, 1 ).onChange( () => {

					generateCity();
					scheduleRebake();

				} );
				gui.add( parameters, 'timeOfDay', 6, 18, 0.1 ).name( 'time of day' ).onChange( () => {

					updateSun();
					scheduleRebake();

				} );
				gui.add( renderer, 'toneMappingExposure', 0.01, 1 ).name( 'exposure' );
				gui.add( parameters, 'gi' ).name( 'global illumination' ).onChange( ( value ) => {

					if ( probes ) probes.visible = value;

				} );
				gui.add( parameters, 'showProbes' ).name( 'show probes' ).onChange( toggleProbesHelper );

				window.addEventListener( 'resize', onWindowResize );

			}

			function updateSun() {

				const t = parameters.timeOfDay;
				const u = ( t - 12 ) / 6; // -1 at sunrise, 0 at noon, +1 at sunset
				const elevation = Math.max( 0, 1 - u * u ) * 72; // degrees above the horizon, peaks at noon
				const azimuth = 90 - u * 55; // the sun swings east → west across the day

				sun.setFromSphericalCoords(
					1,
					THREE.MathUtils.degToRad( 90 - elevation ),
					THREE.MathUtils.degToRad( azimuth )
				);
				sky.sunPosition.value.copy( sun );

				// physically-motivated key light: on a real hazy midday the sun delivers
				// about three times the sky's irradiance onto a horizontal surface, so it
				// is anchored to ~3x the sky dome the probes capture. the longer air path
				// near the horizon dims and warms it ( the fill dims with it, as the
				// environment and probes are re-baked ).

				const sinElevation = Math.sin( THREE.MathUtils.degToRad( elevation ) );
				const transmittance = Math.sqrt( Math.max( sinElevation, 0 ) ); // 0 at the horizon → 1 at the zenith
				sunLight.color.set( 0xffb072 ).lerp( new THREE.Color( 0xfff4e8 ), transmittance );
				sunLight.intensity = 100 * transmittance; // illuminance perpendicular to the rays; the renderer applies N·L per surface
				sunLight.position.copy( sun ).multiplyScalar( 600 );

				// shrink-wrap the shadow camera around the city for this sun angle: project
				// the scene box into light space and fit the ortho bounds and depth range to
				// it, so the map spends its texels only where shadows can actually fall

				const shadowCamera = sunLight.shadow.camera;
				const lightSpace = new THREE.Quaternion().setFromRotationMatrix( new THREE.Matrix4().lookAt( sunLight.position, scene.position, THREE.Object3D.DEFAULT_UP ) ).invert();

				const fit = new THREE.Box3();
				const corner = new THREE.Vector3();

				for ( let i = 0; i < 8; i ++ ) {

					corner.set(
						i & 1 ? cityBounds.max.x : cityBounds.min.x,
						i & 2 ? cityBounds.max.y : cityBounds.min.y,
						i & 4 ? cityBounds.max.z : cityBounds.min.z
					).sub( sunLight.position ).applyQuaternion( lightSpace );

					fit.expandByPoint( corner );

				}

				const pad = 2;
				shadowCamera.left = fit.min.x - pad;
				shadowCamera.right = fit.max.x + pad;
				shadowCamera.bottom = fit.min.y - pad;
				shadowCamera.top = fit.max.y + pad;
				shadowCamera.near = - fit.max.z - pad; // the camera looks down its negative z axis, so depth flips sign
				shadowCamera.far = - fit.min.z + pad;
				shadowCamera.updateProjectionMatrix();

				// re-bake the sky ( without the sun disc ) into the environment map for IBL.
				// reuse one render target so the texture keeps its identity: a fresh texture
				// would force every material to recompile its shader

				sky.showSunDisc.value = false;
				envScene.add( sky );
				envRenderTarget = pmremGenerator.fromScene( envScene, 0, 0.1, 100, { renderTarget: envRenderTarget } );
				scene.environment = envRenderTarget.texture;
				sky.showSunDisc.value = true;
				scene.add( sky );

			}

			function generateCity() {

				if ( cityGroup ) scene.remove( cityGroup );
				if ( cityProxy ) {

					scene.remove( cityProxy );
					cityProxy.geometry.dispose();
					cityProxy.material.dispose();

				}

				city.parameters.seed = parameters.seed;
				cityGroup = city.build( materials );
				scene.add( cityGroup );

				// the box proxy shares the towers just built; it stands in only during the bake
				cityProxy = city.buildProxy();
				cityProxy.visible = false;
				scene.add( cityProxy );

			}

			function bakeProbes() {

				if ( probes === undefined ) {

					probes = new LightProbeGrid( GRID_SIZE.x, GRID_SIZE.y, GRID_SIZE.z, GRID_PROBES.x, GRID_PROBES.y, GRID_PROBES.z );
					probes.position.set( 0, GRID_SIZE.y / 2 + 1, 0 ); // bottom probe layer floats just above the road, never in its plane
					scene.add( probes );

				}

				// swap the detailed city for its box proxy, and hide the probe spheres and the
				// sun disc, so each cubemap captures only the boxes, ground and sky fill. the
				// DirectionalLight supplies the direct sun; a single bounce pass folds the warm
				// stone back into the shade. the proxy is a single draw, so the bake stays cheap

				if ( probesHelper ) probesHelper.visible = false;
				cityGroup.visible = false;
				cityProxy.visible = true;
				sky.showSunDisc.value = false;

				probes.bake( renderer, scene, { cubemapSize: 16, near: 0.1, far: 20000, bounces: 1 } );

				sky.showSunDisc.value = true;
				cityProxy.visible = false;
				cityGroup.visible = true;
				probes.visible = parameters.gi;

				if ( probesHelper ) {

					probesHelper.update();
					probesHelper.visible = parameters.showProbes;

				}

			}

			// re-baking walks the whole city cubemap by cubemap, so coalesce the rapid
			// onChange calls from dragging a slider into a single bake once it settles

			function scheduleRebake() {

				if ( rebakeTimer !== null ) clearTimeout( rebakeTimer );
				rebakeTimer = setTimeout( () => {

					rebakeTimer = null;
					bakeProbes();

				}, 300 );

			}

			function toggleProbesHelper( value ) {

				if ( probesHelper === undefined ) {

					probesHelper = new LightProbeGridHelper( probes, 3 );
					scene.add( probesHelper );

				}

				probesHelper.visible = value;

			}

			function onWindowResize() {

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

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

			}

			function animate() {

				timer.update();
				controls.update( timer.getDelta() );

				renderPipeline.render();

			}

		</script>

	</body>
</html>