@babylonjs/viewer/dist/chunks/hdrFilteringFunctions-CwvCr5Ba.esm.js

The Babylon Viewer aims to simplify a specific but common Babylon.js use case: loading, viewing, and interacting with a 3D model.

import { S as ShaderStore } from './index-MZPybX0H.esm.js';

// Do not edit.
const name$1 = "importanceSampling";
const shader$1 = `fn hemisphereCosSample(u: vec2f)->vec3f {var phi: f32=2.*PI*u.x;var cosTheta2: f32=1.-u.y;var cosTheta: f32=sqrt(cosTheta2);var sinTheta: f32=sqrt(1.-cosTheta2);return vec3f(sinTheta*cos(phi),sinTheta*sin(phi),cosTheta);}
fn hemisphereImportanceSampleDggx(u: vec2f,a: f32)->vec3f {var phi: f32=2.*PI*u.x;var cosTheta2: f32=(1.-u.y)/(1.+(a+1.)*((a-1.)*u.y));var cosTheta: f32=sqrt(cosTheta2);var sinTheta: f32=sqrt(1.-cosTheta2);return vec3f(sinTheta*cos(phi),sinTheta*sin(phi),cosTheta);}
fn hemisphereImportanceSampleDggxAnisotropic(Xi: vec2f,alphaTangent: f32,alphaBitangent: f32)->vec3f
{let alphaT: f32=max(alphaTangent,0.0001);let alphaB: f32=max(alphaBitangent,0.0001);var phi: f32=atan(alphaB/alphaT*tan(2.0f*PI*Xi.x));if (Xi.x>0.5) {phi+=PI; }
let cosPhi: f32=cos(phi);let sinPhi: f32=sin(phi);let alpha2: f32=(cosPhi*cosPhi)/(alphaT*alphaT) +
(sinPhi*sinPhi)/(alphaB*alphaB);let tanTheta2: f32=Xi.y/(1.0f-Xi.y)/alpha2;let cosTheta: f32=1.0f/sqrt(1.0f+tanTheta2);let sinTheta: f32=sqrt(max(0.0f,1.0f-cosTheta*cosTheta));return vec3f(sinTheta*cosPhi,sinTheta*sinPhi,cosTheta);}
fn hemisphereImportanceSampleDCharlie(u: vec2f,a: f32)->vec3f { 
var phi: f32=2.*PI*u.x;var sinTheta: f32=pow(u.y,a/(2.*a+1.));var cosTheta: f32=sqrt(1.-sinTheta*sinTheta);return vec3f(sinTheta*cos(phi),sinTheta*sin(phi),cosTheta);}`;
// Sideeffect
if (!ShaderStore.IncludesShadersStoreWGSL[name$1]) {
    ShaderStore.IncludesShadersStoreWGSL[name$1] = shader$1;
}
/** @internal */
const importanceSamplingWGSL = { name: name$1, shader: shader$1 };

// Do not edit.
const name = "hdrFilteringFunctions";
const shader = `#ifdef NUM_SAMPLES
#if NUM_SAMPLES>0
fn radicalInverse_VdC(value: u32)->f32 
{var bits=(value<<16u) | (value>>16u);bits=((bits & 0x55555555u)<<1u) | ((bits & 0xAAAAAAAAu)>>1u);bits=((bits & 0x33333333u)<<2u) | ((bits & 0xCCCCCCCCu)>>2u);bits=((bits & 0x0F0F0F0Fu)<<4u) | ((bits & 0xF0F0F0F0u)>>4u);bits=((bits & 0x00FF00FFu)<<8u) | ((bits & 0xFF00FF00u)>>8u);return f32(bits)*2.3283064365386963e-10; }
fn hammersley(i: u32,N: u32)->vec2f
{return vec2f( f32(i)/ f32(N),radicalInverse_VdC(i));}
fn log4(x: f32)->f32 {return log2(x)/2.;}
fn uv_to_normal(uv: vec2f)->vec3f {var N: vec3f;var uvRange: vec2f=uv;var theta: f32=uvRange.x*2.0*PI;var phi: f32=uvRange.y*PI;N.x=cos(theta)*sin(phi);N.z=sin(theta)*sin(phi);N.y=cos(phi);return N;}
const NUM_SAMPLES_FLOAT: f32= f32(NUM_SAMPLES);const NUM_SAMPLES_FLOAT_INVERSED: f32=1./NUM_SAMPLES_FLOAT;const K: f32=4.;fn irradiance(
#ifdef CUSTOM_IRRADIANCE_FILTERING_INPUT
CUSTOM_IRRADIANCE_FILTERING_INPUT
#else
inputTexture: texture_cube<f32>,inputSampler: sampler,
#endif
inputN: vec3f,
filteringInfo: vec2f,
diffuseRoughness: f32,
surfaceAlbedo: vec3f,
inputV: vec3f
#ifdef IBL_CDF_FILTERING
,icdfSampler: texture_2d<f32>,icdfSamplerSampler: sampler
#endif
)->vec3f
{var n: vec3f=normalize(inputN);var result: vec3f= vec3f(0.0);
#ifndef IBL_CDF_FILTERING
var tangent: vec3f=select(vec3f(1.,0.,0.),vec3f(0.,0.,1.),abs(n.z)<0.999);tangent=normalize(cross(tangent,n));var bitangent: vec3f=cross(n,tangent);var tbn: mat3x3f= mat3x3f(tangent,bitangent,n);var tbnInverse: mat3x3f=transpose(tbn);
#endif
var maxLevel: f32=filteringInfo.y;var dim0: f32=filteringInfo.x;var omegaP: f32=(4.*PI)/(6.*dim0*dim0);var clampedAlbedo: vec3f=clamp(surfaceAlbedo,vec3f(0.1),vec3f(1.0));for(var i: u32=0u; i<NUM_SAMPLES; i++)
{var Xi: vec2f=hammersley(i,NUM_SAMPLES);
#ifdef IBL_CDF_FILTERING
var T: vec2f;T.x=textureSampleLevel(icdfSampler,icdfSamplerSampler,vec2(Xi.x,0.0),0.0).x;T.y=textureSampleLevel(icdfSampler,icdfSamplerSampler,vec2(T.x,Xi.y),0.0).y;var Ls: vec3f=uv_to_normal(vec2f(1.0-fract(T.x+0.25),T.y));var NoL: f32=dot(n,Ls);var NoV: f32=dot(n,inputV);
#if BASE_DIFFUSE_MODEL==BRDF_DIFFUSE_MODEL_EON
var LoV: f32=dot(Ls,inputV);
#elif BASE_DIFFUSE_MODEL==BRDF_DIFFUSE_MODEL_BURLEY
var H: vec3f=(inputV+Ls)*0.5;var VoH: f32=dot(inputV,H);
#endif 
#else
var Ls: vec3f=hemisphereCosSample(Xi);Ls=normalize(Ls);var Ns: vec3f= vec3f(0.,0.,1.);var NoL: f32=dot(Ns,Ls);var V: vec3f=tbnInverse*inputV;var NoV: f32=dot(Ns,V);
#if BASE_DIFFUSE_MODEL==BRDF_DIFFUSE_MODEL_EON
var LoV: f32=dot(Ls,V);
#elif BASE_DIFFUSE_MODEL==BRDF_DIFFUSE_MODEL_BURLEY
var H: vec3f=(V+Ls)*0.5;var VoH: f32=dot(V,H);
#endif
#endif
if (NoL>0.) {
#ifdef IBL_CDF_FILTERING
var pdf: f32=textureSampleLevel(icdfSampler,icdfSamplerSampler,T,0.0).z;var c: vec3f=textureSampleLevel(inputTexture,inputSampler,Ls,0.0).rgb;
#else
var pdf_inversed: f32=PI/NoL;var omegaS: f32=NUM_SAMPLES_FLOAT_INVERSED*pdf_inversed;var l: f32=log4(omegaS)-log4(omegaP)+log4(K);var mipLevel: f32=clamp(l,0.0,maxLevel);
#ifdef CUSTOM_IRRADIANCE_FILTERING_FUNCTION
CUSTOM_IRRADIANCE_FILTERING_FUNCTION
#else
var c: vec3f=textureSampleLevel(inputTexture,inputSampler,tbn*Ls,mipLevel).rgb;
#endif
#endif
#ifdef GAMMA_INPUT
c=toLinearSpaceVec3(c);
#endif
var diffuseRoughnessTerm: vec3f=vec3f(1.0);
#if BASE_DIFFUSE_MODEL==BRDF_DIFFUSE_MODEL_EON
diffuseRoughnessTerm=diffuseBRDF_EON(clampedAlbedo,diffuseRoughness,NoL,NoV,LoV)*PI;
#elif BASE_DIFFUSE_MODEL==BRDF_DIFFUSE_MODEL_BURLEY
diffuseRoughnessTerm=vec3f(diffuseBRDF_Burley(NoL,NoV,VoH,diffuseRoughness)*PI);
#endif
#ifdef IBL_CDF_FILTERING
var light: vec3f=vec3f(0.0);if (pdf>1e-6) {light=vec3f(1.0)/vec3f(pdf)*c;}
result+=NoL*diffuseRoughnessTerm*light;
#else
result+=c*diffuseRoughnessTerm;
#endif
}}
result=result*NUM_SAMPLES_FLOAT_INVERSED;
#if BASE_DIFFUSE_MODEL==BRDF_DIFFUSE_MODEL_EON
result=result/clampedAlbedo;
#endif
return result;}
fn radiance(alphaG: f32,inputTexture: texture_cube<f32>,inputSampler: sampler,inputN: vec3f,filteringInfo: vec2f)->vec3f
{var n: vec3f=normalize(inputN);var c: vec3f=textureSampleLevel(inputTexture,inputSampler,n,0.0).rgb; 
if (alphaG==0.) {
#ifdef GAMMA_INPUT
c=toLinearSpaceVec3(c);
#endif
return c;} else {var result: vec3f= vec3f(0.);var tangent: vec3f=select(vec3f(1.,0.,0.),vec3f(0.,0.,1.),abs(n.z)<0.999);tangent=normalize(cross(tangent,n));var bitangent: vec3f=cross(n,tangent);var tbn: mat3x3f= mat3x3f(tangent,bitangent,n);var maxLevel: f32=filteringInfo.y;var dim0: f32=filteringInfo.x;var omegaP: f32=(4.*PI)/(6.*dim0*dim0);var weight: f32=0.;for(var i: u32=0u; i<NUM_SAMPLES; i++)
{var Xi: vec2f=hammersley(i,NUM_SAMPLES);var H: vec3f=hemisphereImportanceSampleDggx(Xi,alphaG);var NoV: f32=1.;var NoH: f32=H.z;var NoH2: f32=H.z*H.z;var NoL: f32=2.*NoH2-1.;var L: vec3f= vec3f(2.*NoH*H.x,2.*NoH*H.y,NoL);L=normalize(L);if (NoL>0.) {var pdf_inversed: f32=4./normalDistributionFunction_TrowbridgeReitzGGX(NoH,alphaG);var omegaS: f32=NUM_SAMPLES_FLOAT_INVERSED*pdf_inversed;var l: f32=log4(omegaS)-log4(omegaP)+log4(K);var mipLevel: f32=clamp( f32(l),0.0,maxLevel);weight+=NoL;var c: vec3f=textureSampleLevel(inputTexture,inputSampler,tbn*L,mipLevel).rgb;
#ifdef GAMMA_INPUT
c=toLinearSpaceVec3(c);
#endif
result+=c*NoL;}}
result=result/weight;return result;}}
#ifdef ANISOTROPIC
fn radianceAnisotropic(
alphaTangent: f32, 
alphaBitangent: f32, 
inputTexture: texture_cube<f32>,
inputSampler: sampler,
inputView: vec3f, 
inputTangent: vec3f, 
inputBitangent: vec3f, 
inputNormal: vec3f, 
filteringInfo: vec2f,
noiseInput: vec2f, 
isRefraction: bool,
ior: f32 
)->vec3f {var V: vec3f=inputView;var N: vec3f=inputNormal;var T: vec3f=inputTangent;var B: vec3f=inputBitangent;var result: vec3f=vec3f(0.f);var maxLevel: f32=filteringInfo.y;var dim0: f32=filteringInfo.x;let clampedAlphaT: f32=max(alphaTangent,MINIMUMVARIANCE);let clampedAlphaB: f32=max(alphaBitangent,MINIMUMVARIANCE);var effectiveDim: f32=dim0*sqrt(clampedAlphaT*clampedAlphaB);var omegaP: f32=(4.f*PI)/(6.f*effectiveDim*effectiveDim);let noiseScale: f32=clamp(log2(f32(NUM_SAMPLES))/12.0f,0.0f,1.0f);var weight: f32=0.f;for(var i: u32=0u; i<NUM_SAMPLES; i++)
{var Xi: vec2f=hammersley(i,NUM_SAMPLES);Xi=fract(Xi+noiseInput*mix(0.5f,0.015f,noiseScale)); 
var H_tangent: vec3f=hemisphereImportanceSampleDggxAnisotropic(Xi,clampedAlphaT,clampedAlphaB);var H: vec3f=normalize(H_tangent.x*T+H_tangent.y*B+H_tangent.z*N);var L: vec3f;if (isRefraction) {L=refract(-V,H,1.0/ior);} else {L=reflect(-V,H);}
var NoH: f32=max(dot(N,H),0.001f);var VoH: f32=max(dot(V,H),0.001f);var NoL: f32=max(dot(N,L),0.001f);if (NoL>0.f) {var pdf_inversed: f32=4./normalDistributionFunction_BurleyGGX_Anisotropic(
H_tangent.z,H_tangent.x,H_tangent.y,vec2f(clampedAlphaT,clampedAlphaB)
);var omegaS: f32=NUM_SAMPLES_FLOAT_INVERSED*pdf_inversed;var l: f32=log4(omegaS)-log4(omegaP)+log4(K);var mipLevel: f32=clamp(l,0.0f,maxLevel);weight+=NoL;var c: vec3f=textureSampleLevel(inputTexture,inputSampler,L,mipLevel).rgb;
#if GAMMA_INPUT
c=toLinearSpaceVec3(c);
#endif
result+=c*NoL;}}
result=result/weight;return result;}
#endif
#endif
#endif
`;
// Sideeffect
if (!ShaderStore.IncludesShadersStoreWGSL[name]) {
    ShaderStore.IncludesShadersStoreWGSL[name] = shader;
}
/** @internal */
const hdrFilteringFunctionsWGSL = { name, shader };

export { hdrFilteringFunctionsWGSL as h, importanceSamplingWGSL as i };
//# sourceMappingURL=hdrFilteringFunctions-CwvCr5Ba.esm.js.map