import { CubeReflectionMapping, CubeRefractionMapping, CubeUVReflectionMapping, LinearFilter, NoToneMapping, NoBlending, RGBAFormat, HalfFloatType, BackSide, LinearSRGBColorSpace } from '../constants.js'; import { BufferAttribute } from '../core/BufferAttribute.js'; import { BufferGeometry } from '../core/BufferGeometry.js'; import { Mesh } from '../objects/Mesh.js'; import { OrthographicCamera } from '../cameras/OrthographicCamera.js'; import { PerspectiveCamera } from '../cameras/PerspectiveCamera.js'; import { ShaderMaterial } from '../materials/ShaderMaterial.js'; import { Vector3 } from '../math/Vector3.js'; import { Color } from '../math/Color.js'; import { WebGLRenderTarget } from '../renderers/WebGLRenderTarget.js'; import { MeshBasicMaterial } from '../materials/MeshBasicMaterial.js'; import { BoxGeometry } from '../geometries/BoxGeometry.js'; const LOD_MIN = 4; // The standard deviations (radians) associated with the extra mips. These are // chosen to approximate a Trowbridge-Reitz distribution function times the // geometric shadowing function. These sigma values squared must match the // variance #defines in cube_uv_reflection_fragment.glsl.js. const EXTRA_LOD_SIGMA = [ 0.125, 0.215, 0.35, 0.446, 0.526, 0.582 ]; // The maximum length of the blur for loop. Smaller sigmas will use fewer // samples and exit early, but not recompile the shader. const MAX_SAMPLES = 20; const _flatCamera = /*@__PURE__*/ new OrthographicCamera(); const _clearColor = /*@__PURE__*/ new Color(); let _oldTarget = null; let _oldActiveCubeFace = 0; let _oldActiveMipmapLevel = 0; let _oldXrEnabled = false; // Golden Ratio const PHI = ( 1 + Math.sqrt( 5 ) ) / 2; const INV_PHI = 1 / PHI; // Vertices of a dodecahedron (except the opposites, which represent the // same axis), used as axis directions evenly spread on a sphere. const _axisDirections = [ /*@__PURE__*/ new Vector3( - PHI, INV_PHI, 0 ), /*@__PURE__*/ new Vector3( PHI, INV_PHI, 0 ), /*@__PURE__*/ new Vector3( - INV_PHI, 0, PHI ), /*@__PURE__*/ new Vector3( INV_PHI, 0, PHI ), /*@__PURE__*/ new Vector3( 0, PHI, - INV_PHI ), /*@__PURE__*/ new Vector3( 0, PHI, INV_PHI ), /*@__PURE__*/ new Vector3( - 1, 1, - 1 ), /*@__PURE__*/ new Vector3( 1, 1, - 1 ), /*@__PURE__*/ new Vector3( - 1, 1, 1 ), /*@__PURE__*/ new Vector3( 1, 1, 1 ) ]; /** * This class generates a Prefiltered, Mipmapped Radiance Environment Map * (PMREM) from a cubeMap environment texture. This allows different levels of * blur to be quickly accessed based on material roughness. It is packed into a * special CubeUV format that allows us to perform custom interpolation so that * we can support nonlinear formats such as RGBE. Unlike a traditional mipmap * chain, it only goes down to the LOD_MIN level (above), and then creates extra * even more filtered 'mips' at the same LOD_MIN resolution, associated with * higher roughness levels. In this way we maintain resolution to smoothly * interpolate diffuse lighting while limiting sampling computation. * * Paper: Fast, Accurate Image-Based Lighting * https://drive.google.com/file/d/15y8r_UpKlU9SvV4ILb0C3qCPecS8pvLz/view */ class PMREMGenerator { constructor( renderer ) { this._renderer = renderer; this._pingPongRenderTarget = null; this._lodMax = 0; this._cubeSize = 0; this._lodPlanes = []; this._sizeLods = []; this._sigmas = []; this._blurMaterial = null; this._cubemapMaterial = null; this._equirectMaterial = null; this._compileMaterial( this._blurMaterial ); } /** * Generates a PMREM from a supplied Scene, which can be faster than using an * image if networking bandwidth is low. Optional sigma specifies a blur radius * in radians to be applied to the scene before PMREM generation. Optional near * and far planes ensure the scene is rendered in its entirety (the cubeCamera * is placed at the origin). */ fromScene( scene, sigma = 0, near = 0.1, far = 100 ) { _oldTarget = this._renderer.getRenderTarget(); _oldActiveCubeFace = this._renderer.getActiveCubeFace(); _oldActiveMipmapLevel = this._renderer.getActiveMipmapLevel(); _oldXrEnabled = this._renderer.xr.enabled; this._renderer.xr.enabled = false; this._setSize( 256 ); const cubeUVRenderTarget = this._allocateTargets(); cubeUVRenderTarget.depthBuffer = true; this._sceneToCubeUV( scene, near, far, cubeUVRenderTarget ); if ( sigma > 0 ) { this._blur( cubeUVRenderTarget, 0, 0, sigma ); } this._applyPMREM( cubeUVRenderTarget ); this._cleanup( cubeUVRenderTarget ); return cubeUVRenderTarget; } /** * Generates a PMREM from an equirectangular texture, which can be either LDR * or HDR. The ideal input image size is 1k (1024 x 512), * as this matches best with the 256 x 256 cubemap output. * The smallest supported equirectangular image size is 64 x 32. */ fromEquirectangular( equirectangular, renderTarget = null ) { return this._fromTexture( equirectangular, renderTarget ); } /** * Generates a PMREM from an cubemap texture, which can be either LDR * or HDR. The ideal input cube size is 256 x 256, * as this matches best with the 256 x 256 cubemap output. * The smallest supported cube size is 16 x 16. */ fromCubemap( cubemap, renderTarget = null ) { return this._fromTexture( cubemap, renderTarget ); } /** * Pre-compiles the cubemap shader. You can get faster start-up by invoking this method during * your texture's network fetch for increased concurrency. */ compileCubemapShader() { if ( this._cubemapMaterial === null ) { this._cubemapMaterial = _getCubemapMaterial(); this._compileMaterial( this._cubemapMaterial ); } } /** * Pre-compiles the equirectangular shader. You can get faster start-up by invoking this method during * your texture's network fetch for increased concurrency. */ compileEquirectangularShader() { if ( this._equirectMaterial === null ) { this._equirectMaterial = _getEquirectMaterial(); this._compileMaterial( this._equirectMaterial ); } } /** * Disposes of the PMREMGenerator's internal memory. Note that PMREMGenerator is a static class, * so you should not need more than one PMREMGenerator object. If you do, calling dispose() on * one of them will cause any others to also become unusable. */ dispose() { this._dispose(); if ( this._cubemapMaterial !== null ) this._cubemapMaterial.dispose(); if ( this._equirectMaterial !== null ) this._equirectMaterial.dispose(); } // private interface _setSize( cubeSize ) { this._lodMax = Math.floor( Math.log2( cubeSize ) ); this._cubeSize = Math.pow( 2, this._lodMax ); } _dispose() { if ( this._blurMaterial !== null ) this._blurMaterial.dispose(); if ( this._pingPongRenderTarget !== null ) this._pingPongRenderTarget.dispose(); for ( let i = 0; i < this._lodPlanes.length; i ++ ) { this._lodPlanes[ i ].dispose(); } } _cleanup( outputTarget ) { this._renderer.setRenderTarget( _oldTarget, _oldActiveCubeFace, _oldActiveMipmapLevel ); this._renderer.xr.enabled = _oldXrEnabled; outputTarget.scissorTest = false; _setViewport( outputTarget, 0, 0, outputTarget.width, outputTarget.height ); } _fromTexture( texture, renderTarget ) { if ( texture.mapping === CubeReflectionMapping || texture.mapping === CubeRefractionMapping ) { this._setSize( texture.image.length === 0 ? 16 : ( texture.image[ 0 ].width || texture.image[ 0 ].image.width ) ); } else { // Equirectangular this._setSize( texture.image.width / 4 ); } _oldTarget = this._renderer.getRenderTarget(); _oldActiveCubeFace = this._renderer.getActiveCubeFace(); _oldActiveMipmapLevel = this._renderer.getActiveMipmapLevel(); _oldXrEnabled = this._renderer.xr.enabled; this._renderer.xr.enabled = false; const cubeUVRenderTarget = renderTarget || this._allocateTargets(); this._textureToCubeUV( texture, cubeUVRenderTarget ); this._applyPMREM( cubeUVRenderTarget ); this._cleanup( cubeUVRenderTarget ); return cubeUVRenderTarget; } _allocateTargets() { const width = 3 * Math.max( this._cubeSize, 16 * 7 ); const height = 4 * this._cubeSize; const params = { magFilter: LinearFilter, minFilter: LinearFilter, generateMipmaps: false, type: HalfFloatType, format: RGBAFormat, colorSpace: LinearSRGBColorSpace, depthBuffer: false }; const cubeUVRenderTarget = _createRenderTarget( width, height, params ); if ( this._pingPongRenderTarget === null || this._pingPongRenderTarget.width !== width || this._pingPongRenderTarget.height !== height ) { if ( this._pingPongRenderTarget !== null ) { this._dispose(); } this._pingPongRenderTarget = _createRenderTarget( width, height, params ); const { _lodMax } = this; ( { sizeLods: this._sizeLods, lodPlanes: this._lodPlanes, sigmas: this._sigmas } = _createPlanes( _lodMax ) ); this._blurMaterial = _getBlurShader( _lodMax, width, height ); } return cubeUVRenderTarget; } _compileMaterial( material ) { const tmpMesh = new Mesh( this._lodPlanes[ 0 ], material ); this._renderer.compile( tmpMesh, _flatCamera ); } _sceneToCubeUV( scene, near, far, cubeUVRenderTarget ) { const fov = 90; const aspect = 1; const cubeCamera = new PerspectiveCamera( fov, aspect, near, far ); const upSign = [ 1, - 1, 1, 1, 1, 1 ]; const forwardSign = [ 1, 1, 1, - 1, - 1, - 1 ]; const renderer = this._renderer; const originalAutoClear = renderer.autoClear; const toneMapping = renderer.toneMapping; renderer.getClearColor( _clearColor ); renderer.toneMapping = NoToneMapping; renderer.autoClear = false; const backgroundMaterial = new MeshBasicMaterial( { name: 'PMREM.Background', side: BackSide, depthWrite: false, depthTest: false, } ); const backgroundBox = new Mesh( new BoxGeometry(), backgroundMaterial ); let useSolidColor = false; const background = scene.background; if ( background ) { if ( background.isColor ) { backgroundMaterial.color.copy( background ); scene.background = null; useSolidColor = true; } } else { backgroundMaterial.color.copy( _clearColor ); useSolidColor = true; } for ( let i = 0; i < 6; i ++ ) { const col = i % 3; if ( col === 0 ) { cubeCamera.up.set( 0, upSign[ i ], 0 ); cubeCamera.lookAt( forwardSign[ i ], 0, 0 ); } else if ( col === 1 ) { cubeCamera.up.set( 0, 0, upSign[ i ] ); cubeCamera.lookAt( 0, forwardSign[ i ], 0 ); } else { cubeCamera.up.set( 0, upSign[ i ], 0 ); cubeCamera.lookAt( 0, 0, forwardSign[ i ] ); } const size = this._cubeSize; _setViewport( cubeUVRenderTarget, col * size, i > 2 ? size : 0, size, size ); renderer.setRenderTarget( cubeUVRenderTarget ); if ( useSolidColor ) { renderer.render( backgroundBox, cubeCamera ); } renderer.render( scene, cubeCamera ); } backgroundBox.geometry.dispose(); backgroundBox.material.dispose(); renderer.toneMapping = toneMapping; renderer.autoClear = originalAutoClear; scene.background = background; } _textureToCubeUV( texture, cubeUVRenderTarget ) { const renderer = this._renderer; const isCubeTexture = ( texture.mapping === CubeReflectionMapping || texture.mapping === CubeRefractionMapping ); if ( isCubeTexture ) { if ( this._cubemapMaterial === null ) { this._cubemapMaterial = _getCubemapMaterial(); } this._cubemapMaterial.uniforms.flipEnvMap.value = ( texture.isRenderTargetTexture === false ) ? - 1 : 1; } else { if ( this._equirectMaterial === null ) { this._equirectMaterial = _getEquirectMaterial(); } } const material = isCubeTexture ? this._cubemapMaterial : this._equirectMaterial; const mesh = new Mesh( this._lodPlanes[ 0 ], material ); const uniforms = material.uniforms; uniforms[ 'envMap' ].value = texture; const size = this._cubeSize; _setViewport( cubeUVRenderTarget, 0, 0, 3 * size, 2 * size ); renderer.setRenderTarget( cubeUVRenderTarget ); renderer.render( mesh, _flatCamera ); } _applyPMREM( cubeUVRenderTarget ) { const renderer = this._renderer; const autoClear = renderer.autoClear; renderer.autoClear = false; const n = this._lodPlanes.length; for ( let i = 1; i < n; i ++ ) { const sigma = Math.sqrt( this._sigmas[ i ] * this._sigmas[ i ] - this._sigmas[ i - 1 ] * this._sigmas[ i - 1 ] ); const poleAxis = _axisDirections[ ( n - i - 1 ) % _axisDirections.length ]; this._blur( cubeUVRenderTarget, i - 1, i, sigma, poleAxis ); } renderer.autoClear = autoClear; } /** * This is a two-pass Gaussian blur for a cubemap. Normally this is done * vertically and horizontally, but this breaks down on a cube. Here we apply * the blur latitudinally (around the poles), and then longitudinally (towards * the poles) to approximate the orthogonally-separable blur. It is least * accurate at the poles, but still does a decent job. */ _blur( cubeUVRenderTarget, lodIn, lodOut, sigma, poleAxis ) { const pingPongRenderTarget = this._pingPongRenderTarget; this._halfBlur( cubeUVRenderTarget, pingPongRenderTarget, lodIn, lodOut, sigma, 'latitudinal', poleAxis ); this._halfBlur( pingPongRenderTarget, cubeUVRenderTarget, lodOut, lodOut, sigma, 'longitudinal', poleAxis ); } _halfBlur( targetIn, targetOut, lodIn, lodOut, sigmaRadians, direction, poleAxis ) { const renderer = this._renderer; const blurMaterial = this._blurMaterial; if ( direction !== 'latitudinal' && direction !== 'longitudinal' ) { console.error( 'blur direction must be either latitudinal or longitudinal!' ); } // Number of standard deviations at which to cut off the discrete approximation. const STANDARD_DEVIATIONS = 3; const blurMesh = new Mesh( this._lodPlanes[ lodOut ], blurMaterial ); const blurUniforms = blurMaterial.uniforms; const pixels = this._sizeLods[ lodIn ] - 1; const radiansPerPixel = isFinite( sigmaRadians ) ? Math.PI / ( 2 * pixels ) : 2 * Math.PI / ( 2 * MAX_SAMPLES - 1 ); const sigmaPixels = sigmaRadians / radiansPerPixel; const samples = isFinite( sigmaRadians ) ? 1 + Math.floor( STANDARD_DEVIATIONS * sigmaPixels ) : MAX_SAMPLES; if ( samples > MAX_SAMPLES ) { console.warn( `sigmaRadians, ${ sigmaRadians}, is too large and will clip, as it requested ${ samples} samples when the maximum is set to ${MAX_SAMPLES}` ); } const weights = []; let sum = 0; for ( let i = 0; i < MAX_SAMPLES; ++ i ) { const x = i / sigmaPixels; const weight = Math.exp( - x * x / 2 ); weights.push( weight ); if ( i === 0 ) { sum += weight; } else if ( i < samples ) { sum += 2 * weight; } } for ( let i = 0; i < weights.length; i ++ ) { weights[ i ] = weights[ i ] / sum; } blurUniforms[ 'envMap' ].value = targetIn.texture; blurUniforms[ 'samples' ].value = samples; blurUniforms[ 'weights' ].value = weights; blurUniforms[ 'latitudinal' ].value = direction === 'latitudinal'; if ( poleAxis ) { blurUniforms[ 'poleAxis' ].value = poleAxis; } const { _lodMax } = this; blurUniforms[ 'dTheta' ].value = radiansPerPixel; blurUniforms[ 'mipInt' ].value = _lodMax - lodIn; const outputSize = this._sizeLods[ lodOut ]; const x = 3 * outputSize * ( lodOut > _lodMax - LOD_MIN ? lodOut - _lodMax + LOD_MIN : 0 ); const y = 4 * ( this._cubeSize - outputSize ); _setViewport( targetOut, x, y, 3 * outputSize, 2 * outputSize ); renderer.setRenderTarget( targetOut ); renderer.render( blurMesh, _flatCamera ); } } function _createPlanes( lodMax ) { const lodPlanes = []; const sizeLods = []; const sigmas = []; let lod = lodMax; const totalLods = lodMax - LOD_MIN + 1 + EXTRA_LOD_SIGMA.length; for ( let i = 0; i < totalLods; i ++ ) { const sizeLod = Math.pow( 2, lod ); sizeLods.push( sizeLod ); let sigma = 1.0 / sizeLod; if ( i > lodMax - LOD_MIN ) { sigma = EXTRA_LOD_SIGMA[ i - lodMax + LOD_MIN - 1 ]; } else if ( i === 0 ) { sigma = 0; } sigmas.push( sigma ); const texelSize = 1.0 / ( sizeLod - 2 ); const min = - texelSize; const max = 1 + texelSize; const uv1 = [ min, min, max, min, max, max, min, min, max, max, min, max ]; const cubeFaces = 6; const vertices = 6; const positionSize = 3; const uvSize = 2; const faceIndexSize = 1; const position = new Float32Array( positionSize * vertices * cubeFaces ); const uv = new Float32Array( uvSize * vertices * cubeFaces ); const faceIndex = new Float32Array( faceIndexSize * vertices * cubeFaces ); for ( let face = 0; face < cubeFaces; face ++ ) { const x = ( face % 3 ) * 2 / 3 - 1; const y = face > 2 ? 0 : - 1; const coordinates = [ x, y, 0, x + 2 / 3, y, 0, x + 2 / 3, y + 1, 0, x, y, 0, x + 2 / 3, y + 1, 0, x, y + 1, 0 ]; position.set( coordinates, positionSize * vertices * face ); uv.set( uv1, uvSize * vertices * face ); const fill = [ face, face, face, face, face, face ]; faceIndex.set( fill, faceIndexSize * vertices * face ); } const planes = new BufferGeometry(); planes.setAttribute( 'position', new BufferAttribute( position, positionSize ) ); planes.setAttribute( 'uv', new BufferAttribute( uv, uvSize ) ); planes.setAttribute( 'faceIndex', new BufferAttribute( faceIndex, faceIndexSize ) ); lodPlanes.push( planes ); if ( lod > LOD_MIN ) { lod --; } } return { lodPlanes, sizeLods, sigmas }; } function _createRenderTarget( width, height, params ) { const cubeUVRenderTarget = new WebGLRenderTarget( width, height, params ); cubeUVRenderTarget.texture.mapping = CubeUVReflectionMapping; cubeUVRenderTarget.texture.name = 'PMREM.cubeUv'; cubeUVRenderTarget.scissorTest = true; return cubeUVRenderTarget; } function _setViewport( target, x, y, width, height ) { target.viewport.set( x, y, width, height ); target.scissor.set( x, y, width, height ); } function _getBlurShader( lodMax, width, height ) { const weights = new Float32Array( MAX_SAMPLES ); const poleAxis = new Vector3( 0, 1, 0 ); const shaderMaterial = new ShaderMaterial( { name: 'SphericalGaussianBlur', defines: { 'n': MAX_SAMPLES, 'CUBEUV_TEXEL_WIDTH': 1.0 / width, 'CUBEUV_TEXEL_HEIGHT': 1.0 / height, 'CUBEUV_MAX_MIP': `${lodMax}.0`, }, uniforms: { 'envMap': { value: null }, 'samples': { value: 1 }, 'weights': { value: weights }, 'latitudinal': { value: false }, 'dTheta': { value: 0 }, 'mipInt': { value: 0 }, 'poleAxis': { value: poleAxis } }, vertexShader: _getCommonVertexShader(), fragmentShader: /* glsl */` precision mediump float; precision mediump int; varying vec3 vOutputDirection; uniform sampler2D envMap; uniform int samples; uniform float weights[ n ]; uniform bool latitudinal; uniform float dTheta; uniform float mipInt; uniform vec3 poleAxis; #define ENVMAP_TYPE_CUBE_UV #include vec3 getSample( float theta, vec3 axis ) { float cosTheta = cos( theta ); // Rodrigues' axis-angle rotation vec3 sampleDirection = vOutputDirection * cosTheta + cross( axis, vOutputDirection ) * sin( theta ) + axis * dot( axis, vOutputDirection ) * ( 1.0 - cosTheta ); return bilinearCubeUV( envMap, sampleDirection, mipInt ); } void main() { vec3 axis = latitudinal ? poleAxis : cross( poleAxis, vOutputDirection ); if ( all( equal( axis, vec3( 0.0 ) ) ) ) { axis = vec3( vOutputDirection.z, 0.0, - vOutputDirection.x ); } axis = normalize( axis ); gl_FragColor = vec4( 0.0, 0.0, 0.0, 1.0 ); gl_FragColor.rgb += weights[ 0 ] * getSample( 0.0, axis ); for ( int i = 1; i < n; i++ ) { if ( i >= samples ) { break; } float theta = dTheta * float( i ); gl_FragColor.rgb += weights[ i ] * getSample( -1.0 * theta, axis ); gl_FragColor.rgb += weights[ i ] * getSample( theta, axis ); } } `, blending: NoBlending, depthTest: false, depthWrite: false } ); return shaderMaterial; } function _getEquirectMaterial() { return new ShaderMaterial( { name: 'EquirectangularToCubeUV', uniforms: { 'envMap': { value: null } }, vertexShader: _getCommonVertexShader(), fragmentShader: /* glsl */` precision mediump float; precision mediump int; varying vec3 vOutputDirection; uniform sampler2D envMap; #include void main() { vec3 outputDirection = normalize( vOutputDirection ); vec2 uv = equirectUv( outputDirection ); gl_FragColor = vec4( texture2D ( envMap, uv ).rgb, 1.0 ); } `, blending: NoBlending, depthTest: false, depthWrite: false } ); } function _getCubemapMaterial() { return new ShaderMaterial( { name: 'CubemapToCubeUV', uniforms: { 'envMap': { value: null }, 'flipEnvMap': { value: - 1 } }, vertexShader: _getCommonVertexShader(), fragmentShader: /* glsl */` precision mediump float; precision mediump int; uniform float flipEnvMap; varying vec3 vOutputDirection; uniform samplerCube envMap; void main() { gl_FragColor = textureCube( envMap, vec3( flipEnvMap * vOutputDirection.x, vOutputDirection.yz ) ); } `, blending: NoBlending, depthTest: false, depthWrite: false } ); } function _getCommonVertexShader() { return /* glsl */` precision mediump float; precision mediump int; attribute float faceIndex; varying vec3 vOutputDirection; // RH coordinate system; PMREM face-indexing convention vec3 getDirection( vec2 uv, float face ) { uv = 2.0 * uv - 1.0; vec3 direction = vec3( uv, 1.0 ); if ( face == 0.0 ) { direction = direction.zyx; // ( 1, v, u ) pos x } else if ( face == 1.0 ) { direction = direction.xzy; direction.xz *= -1.0; // ( -u, 1, -v ) pos y } else if ( face == 2.0 ) { direction.x *= -1.0; // ( -u, v, 1 ) pos z } else if ( face == 3.0 ) { direction = direction.zyx; direction.xz *= -1.0; // ( -1, v, -u ) neg x } else if ( face == 4.0 ) { direction = direction.xzy; direction.xy *= -1.0; // ( -u, -1, v ) neg y } else if ( face == 5.0 ) { direction.z *= -1.0; // ( u, v, -1 ) neg z } return direction; } void main() { vOutputDirection = getDirection( uv, faceIndex ); gl_Position = vec4( position, 1.0 ); } `; } export { PMREMGenerator };