Sky: Add WebGPURenderer version.

examples/files.json

@@ -395,6 +395,7 @@
 		"webgpu_skinning",
 		"webgpu_skinning_instancing",
 		"webgpu_skinning_points",
+		"webgpu_sky",
 		"webgpu_sprites",
 		"webgpu_storage_buffer",
 		"webgpu_texturegrad",

examples/jsm/objects/SkyGPU.js

@@ -0,0 +1,190 @@
+import {
+	BackSide,
+	BoxGeometry,
+	Mesh,
+	NodeMaterial,
+	Vector3
+} from 'three';
+import { float, tslFn, vec3, acos, add, mul, clamp, cos, dot, exp, max, mix, modelViewProjection, normalize, positionWorld, pow, smoothstep, sub, varying, 	varyingProperty, vec4, uniform } from 'three/tsl';
+
+/**
+ * Based on "A Practical Analytic Model for Daylight"
+ * aka The Preetham Model, the de facto standard analytic skydome model
+ * https://www.researchgate.net/publication/220720443_A_Practical_Analytic_Model_for_Daylight
+ *
+ * First implemented by Simon Wallner
+ * http://simonwallner.at/project/atmospheric-scattering/
+ *
+ * Improved by Martin Upitis
+ * http://blenderartists.org/forum/showthread.php?245954-preethams-sky-impementation-HDR
+ *
+ * Three.js integration by zz85 http://twitter.com/blurspline
+*/
+
+class Sky extends Mesh {
+
+	constructor() {
+
+		const material = new NodeMaterial();
+
+		super( new BoxGeometry( 1, 1, 1 ), material );
+
+		this.turbidity = uniform( 2 );
+		this.rayleigh = uniform( 1 );
+		this.mieCoefficient = uniform( 0.005 );
+		this.mieDirectionalG = uniform( 0.8 );
+		this.sunPosition = uniform( new Vector3() );
+		this.up = uniform( new Vector3( 0, 1, 0 ) );
+		this.cameraPosition = uniform( new Vector3() ).label( 'cameraPosition' ).onRenderUpdate( ( { camera }, self ) => self.value.setFromMatrixPosition( camera.matrixWorld ) ); // TODO replace with cameraPosition from CameraNode
+
+		this.isSky = true;
+
+		const vertexNode = /*@__PURE__*/ tslFn( () => {
+
+			// constants for atmospheric scattering
+			const e = float( 2.71828182845904523536028747135266249775724709369995957 );
+			// const pi = float( 3.141592653589793238462643383279502884197169 );
+
+			// wavelength of used primaries, according to preetham
+			// const lambda = vec3( 680E-9, 550E-9, 450E-9 );
+			// this pre-calcuation replaces older TotalRayleigh(vec3 lambda) function:
+			// (8.0 * pow(pi, 3.0) * pow(pow(n, 2.0) - 1.0, 2.0) * (6.0 + 3.0 * pn)) / (3.0 * N * pow(lambda, vec3(4.0)) * (6.0 - 7.0 * pn))
+			const totalRayleigh = vec3( 5.804542996261093E-6, 1.3562911419845635E-5, 3.0265902468824876E-5 );
+
+			// mie stuff
+			// K coefficient for the primaries
+			// const v = float( 4.0 );
+			// const K = vec3( 0.686, 0.678, 0.666 );
+			// MieConst = pi * pow( ( 2.0 * pi ) / lambda, vec3( v - 2.0 ) ) * K
+			const MieConst = vec3( 1.8399918514433978E14, 2.7798023919660528E14, 4.0790479543861094E14 );
+
+			// earth shadow hack
+			// cutoffAngle = pi / 1.95;
+			const cutoffAngle = float( 1.6110731556870734 );
+			const steepness = float( 1.5 );
+			const EE = float( 1000.0 );
+
+			// varying sun position
+
+			const vSunDirection = normalize( this.sunPosition );
+			varyingProperty( 'vec3', 'vSunDirection' ).assign( vSunDirection );
+
+			// varying sun intensity
+
+			const angle = dot( vSunDirection, this.up );
+			const zenithAngleCos = clamp( angle, - 1, 1 );
+			const sunIntensity = EE.mul( max( 0.0, float( 1.0 ).sub( pow( e, cutoffAngle.sub( acos( zenithAngleCos ) ).div( steepness ).negate() ) ) ) );
+			varyingProperty( 'float', 'vSunE' ).assign( sunIntensity );
+
+			// varying sun fade
+
+			const vSunfade = float( 1.0 ).sub( clamp( float( 1.0 ).sub( exp( this.sunPosition.y.div( 450000.0 ) ) ), 0, 1 ) );
+			varyingProperty( 'float', 'vSunfade' ).assign( vSunfade );
+
+			// varying vBetaR
+
+			const rayleighCoefficient = this.rayleigh.sub( float( 1.0 ).mul( float( 1.0 ).sub( vSunfade ) ) );
+
+			// extinction (absorbtion + out scattering)
+			// rayleigh coefficients
+			varyingProperty( 'vec3', 'vBetaR' ).assign( totalRayleigh.mul( rayleighCoefficient ) );
+
+			// varying vBetaM
+
+			const c = float( 0.2 ).mul( this.turbidity ).mul( 10E-18 );
+			const totalMie = float( 0.434 ).mul( c ).mul( MieConst );
+
+			varyingProperty( 'vec3', 'vBetaM' ).assign( totalMie.mul( this.mieCoefficient ) );
+
+			// position
+
+			const position = modelViewProjection();
+			position.z.assign( position.w ); // set z to camera.far
+
+			return position;
+
+		} )();
+
+		const fragmentNode = /*@__PURE__*/ tslFn( () => {
+
+			const vSunDirection = varying( vec3(), 'vSunDirection' );
+			const vSunE = varying( float(), 'vSunE' );
+			const vSunfade = varying( float(), 'vSunfade' );
+			const vBetaR = varying( vec3(), 'vBetaR' );
+			const vBetaM = varying( vec3(), 'vBetaM' );
+
+			// constants for atmospheric scattering
+			const pi = float( 3.141592653589793238462643383279502884197169 );
+
+			// optical length at zenith for molecules
+			const rayleighZenithLength = float( 8.4E3 );
+			const mieZenithLength = float( 1.25E3 );
+			// 66 arc seconds -> degrees, and the cosine of that
+			const sunAngularDiameterCos = float( 0.999956676946448443553574619906976478926848692873900859324 );
+
+			// 3.0 / ( 16.0 * pi )
+			const THREE_OVER_SIXTEENPI = float( 0.05968310365946075 );
+			// 1.0 / ( 4.0 * pi )
+			const ONE_OVER_FOURPI = float( 0.07957747154594767 );
+
+			//
+
+			const direction = normalize( positionWorld.sub( this.cameraPosition ) );
+
+			// optical length
+			// cutoff angle at 90 to avoid singularity in next formula.
+			const zenithAngle = acos( max( 0.0, dot( this.up, direction ) ) );
+			const inverse = float( 1.0 ).div( cos( zenithAngle ).add( float( 0.15 ).mul( pow( float( 93.885 ).sub( zenithAngle.mul( 180.0 ).div( pi ) ), - 1.253 ) ) ) );
+			const sR = rayleighZenithLength.mul( inverse );
+			const sM = mieZenithLength.mul( inverse );
+
+			// combined extinction factor
+			const Fex = exp( mul( vBetaR, sR ).add( mul( vBetaM, sM ) ).negate() );
+
+			// in scattering
+			const cosTheta = dot( direction, vSunDirection );
+
+			// betaRTheta
+
+			const c = cosTheta.mul( 0.5 ).add( 0.5 );
+			const rPhase = THREE_OVER_SIXTEENPI.mul( float( 1.0 ).add( pow( c, 2.0 ) ) );
+			const betaRTheta = vBetaR.mul( rPhase );
+
+			// betaMTheta
+
+			const g2 = pow( this.mieDirectionalG, 2.0 );
+			const inv = float( 1.0 ).div( pow( float( 1.0 ).sub( float( 2.0 ).mul( this.mieDirectionalG ).mul( cosTheta ) ).add( g2 ), 1.5 ) );
+			const mPhase = ONE_OVER_FOURPI.mul( float( 1.0 ).sub( g2 ) ).mul( inv );
+			const betaMTheta = vBetaM.mul( mPhase );
+
+			const Lin = pow( vSunE.mul( add( betaRTheta, betaMTheta ).div( add( vBetaR, vBetaM ) ) ).mul( sub( 1.0, Fex ) ), vec3( 1.5 ) );
+			Lin.mulAssign( mix( vec3( 1.0 ), pow( vSunE.mul( add( betaRTheta, betaMTheta ).div( add( vBetaR, vBetaM ) ) ).mul( Fex ), vec3( 1.0 / 2.0 ) ), clamp( pow( sub( 1.0, dot( this.up, vSunDirection ) ), 5.0 ), 0.0, 1.0 ) ) );
+
+			// nightsky
+
+			const L0 = vec3( 0.1 ).mul( Fex );
+
+			// composition + solar disc
+			const sundisk = smoothstep( sunAngularDiameterCos, sunAngularDiameterCos.add( 0.00002 ), cosTheta );
+			L0.addAssign( vSunE.mul( 19000.0 ).mul( Fex ).mul( sundisk ) );
+
+			const texColor = add( Lin, L0 ).mul( 0.04 ).add( vec3( 0.0, 0.0003, 0.00075 ) );
+
+			const retColor = pow( texColor, vec3( float( 1.0 ).div( float( 1.2 ).add( vSunfade.mul( 1.2 ) ) ) ) );
+
+			return vec4( retColor, 1.0 );
+
+		} )();
+
+		material.normals = false;
+		material.side = BackSide;
+		material.depthWrite = false;
+
+		material.vertexNode = vertexNode;
+		material.fragmentNode = fragmentNode;
+
+	}
+
+}
+
+export { Sky };

examples/webgpu_sky.html

@@ -0,0 +1,136 @@
+<!DOCTYPE html>
+<html lang="en">
+	<head>
+		<title>three.js webgpu - sky</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 - sky + sun shader
+		</div>
+
+		<script type="importmap">
+			{
+				"imports": {
+					"three": "../build/three.webgpu.js",
+					"three/tsl": "../build/three.webgpu.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 { Sky } from 'three/addons/objects/SkyGPU.js';
+
+			let camera, scene, renderer;
+
+			let sky, sun;
+
+			init();
+
+			function initSky() {
+
+				// Add Sky
+				sky = new Sky();
+				sky.scale.setScalar( 450000 );
+				scene.add( sky );
+
+				sun = new THREE.Vector3();
+
+				/// GUI
+
+				const effectController = {
+					turbidity: 10,
+					rayleigh: 3,
+					mieCoefficient: 0.005,
+					mieDirectionalG: 0.7,
+					elevation: 2,
+					azimuth: 180,
+					exposure: renderer.toneMappingExposure
+				};
+
+				function guiChanged() {
+
+					sky.turbidity.value = effectController.turbidity;
+					sky.rayleigh.value = effectController.rayleigh;
+					sky.mieCoefficient.value = effectController.mieCoefficient;
+					sky.mieDirectionalG.value = effectController.mieDirectionalG;
+
+					const phi = THREE.MathUtils.degToRad( 90 - effectController.elevation );
+					const theta = THREE.MathUtils.degToRad( effectController.azimuth );
+
+					sun.setFromSphericalCoords( 1, phi, theta );
+
+					sky.sunPosition.value.copy( sun );
+
+					renderer.toneMappingExposure = effectController.exposure;
+
+				}
+
+				const gui = new GUI();
+
+				gui.add( effectController, 'turbidity', 0.0, 20.0, 0.1 ).onChange( guiChanged );
+				gui.add( effectController, 'rayleigh', 0.0, 4, 0.001 ).onChange( guiChanged );
+				gui.add( effectController, 'mieCoefficient', 0.0, 0.1, 0.001 ).onChange( guiChanged );
+				gui.add( effectController, 'mieDirectionalG', 0.0, 1, 0.001 ).onChange( guiChanged );
+				gui.add( effectController, 'elevation', 0, 90, 0.1 ).onChange( guiChanged );
+				gui.add( effectController, 'azimuth', - 180, 180, 0.1 ).onChange( guiChanged );
+				gui.add( effectController, 'exposure', 0, 1, 0.0001 ).onChange( guiChanged );
+
+				guiChanged();
+
+			}
+
+			function init() {
+
+				camera = new THREE.PerspectiveCamera( 60, window.innerWidth / window.innerHeight, 100, 2000000 );
+				camera.position.set( 0, 100, 2000 );
+
+				scene = new THREE.Scene();
+
+				renderer = new THREE.WebGPURenderer();
+				renderer.setPixelRatio( window.devicePixelRatio );
+				renderer.setSize( window.innerWidth, window.innerHeight );
+				renderer.setAnimationLoop( animate );
+				renderer.toneMapping = THREE.ACESFilmicToneMapping;
+				renderer.toneMappingExposure = 0.5;
+				document.body.appendChild( renderer.domElement );
+
+				const controls = new OrbitControls( camera, renderer.domElement );
+				//controls.maxPolarAngle = Math.PI / 2;
+				controls.enableZoom = false;
+				controls.enablePan = false;
+
+				initSky();
+
+				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>