@babylonjs/viewer
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The Babylon Viewer aims to simplify a specific but common Babylon.js use case: loading, viewing, and interacting with a 3D model.
177 lines (173 loc) • 9.05 kB
JavaScript
import { S as ShaderStore } from './index-MZPybX0H.esm.js';
// Do not edit.
const name$1 = "importanceSampling";
const shader$1 = `vec3 hemisphereCosSample(vec2 u) {float phi=2.*PI*u.x;float cosTheta2=1.-u.y;float cosTheta=sqrt(cosTheta2);float sinTheta=sqrt(1.-cosTheta2);return vec3(sinTheta*cos(phi),sinTheta*sin(phi),cosTheta);}
vec3 hemisphereImportanceSampleDggx(vec2 u,float a) {float phi=2.*PI*u.x;float cosTheta2=(1.-u.y)/(1.+(a+1.)*((a-1.)*u.y));float cosTheta=sqrt(cosTheta2);float sinTheta=sqrt(1.-cosTheta2);return vec3(sinTheta*cos(phi),sinTheta*sin(phi),cosTheta);}
vec3 hemisphereImportanceSampleDggxAnisotropic(vec2 Xi,float alphaTangent,float alphaBitangent)
{alphaTangent=max(alphaTangent,0.0001);alphaBitangent=max(alphaBitangent,0.0001);float phi=atan(alphaBitangent/alphaTangent*tan(2.0*3.14159265*Xi.x));if (Xi.x>0.5) phi+=3.14159265;
float cosPhi=cos(phi);float sinPhi=sin(phi);float alpha2=(cosPhi*cosPhi)/(alphaTangent*alphaTangent) +
(sinPhi*sinPhi)/(alphaBitangent*alphaBitangent);float tanTheta2=Xi.y/(1.0-Xi.y)/alpha2;float cosTheta=1.0/sqrt(1.0+tanTheta2);float sinTheta=sqrt(max(0.0,1.0-cosTheta*cosTheta));return vec3(sinTheta*cosPhi,sinTheta*sinPhi,cosTheta);}
vec3 hemisphereImportanceSampleDCharlie(vec2 u,float a) {
float phi=2.*PI*u.x;float sinTheta=pow(u.y,a/(2.*a+1.));float cosTheta=sqrt(1.-sinTheta*sinTheta);return vec3(sinTheta*cos(phi),sinTheta*sin(phi),cosTheta);}`;
// Sideeffect
if (!ShaderStore.IncludesShadersStore[name$1]) {
ShaderStore.IncludesShadersStore[name$1] = shader$1;
}
/** @internal */
const importanceSampling = { name: name$1, shader: shader$1 };
// Do not edit.
const name = "hdrFilteringFunctions";
const shader = `
float radicalInverse_VdC(uint bits)
{bits=(bits<<16u) | (bits>>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 float(bits)*2.3283064365386963e-10; }
vec2 hammersley(uint i,uint N)
{return vec2(float(i)/float(N),radicalInverse_VdC(i));}
float vanDerCorpus(int n,int base)
{float invBase=1.0/float(base);float denom =1.0;float result =0.0;for(int i=0; i<32; ++i)
{if(n>0)
{denom =mod(float(n),2.0);result+=denom*invBase;invBase=invBase/2.0;n =int(float(n)/2.0);}}
return result;}
vec2 hammersley(int i,int N)
{return vec2(float(i)/float(N),vanDerCorpus(i,2));}
float log4(float x) {return log2(x)/2.;}
vec3 uv_to_normal(vec2 uv) {vec3 N;vec2 uvRange=uv;float theta=uvRange.x*2.*PI;float phi=uvRange.y*PI;float sinPhi=sin(phi);N.x=cos(theta)*sinPhi;N.z=sin(theta)*sinPhi;N.y=cos(phi);return N;}
const float NUM_SAMPLES_FLOAT=float(NUM_SAMPLES);const float NUM_SAMPLES_FLOAT_INVERSED=1./NUM_SAMPLES_FLOAT;const float K=4.;
vec3 irradiance(
#ifdef CUSTOM_IRRADIANCE_FILTERING_INPUT
CUSTOM_IRRADIANCE_FILTERING_INPUT
#else
samplerCube inputTexture,
#endif
vec3 inputN,vec2 filteringInfo,
float diffuseRoughness,
vec3 surfaceAlbedo,
vec3 inputV
#if IBL_CDF_FILTERING
,sampler2D icdfSampler
#endif
)
{vec3 n=normalize(inputN);vec3 result=vec3(0.);
vec3 tangent=abs(n.z)<0.999 ? vec3(0.,0.,1.) : vec3(1.,0.,0.);tangent=normalize(cross(tangent,n));vec3 bitangent=cross(n,tangent);mat3 tbn=mat3(tangent,bitangent,n);mat3 tbnInverse=mat3(tangent.x,bitangent.x,n.x,tangent.y,bitangent.y,n.y,tangent.z,bitangent.z,n.z);
float maxLevel=filteringInfo.y;float dim0=filteringInfo.x;float omegaP=(4.*PI)/(6.*dim0*dim0);vec3 clampedAlbedo=clamp(surfaceAlbedo,vec3(0.1),vec3(1.0));
for(uint i=0u; i<NUM_SAMPLES; ++i)
for(int i=0; i<NUM_SAMPLES; ++i)
{vec2 Xi=hammersley(i,NUM_SAMPLES);
vec2 T;T.x=texture2D(icdfSampler,vec2(Xi.x,0.)).x;T.y=texture2D(icdfSampler,vec2(T.x,Xi.y)).y;vec3 Ls=uv_to_normal(vec2(1.0-fract(T.x+0.25),T.y));float NoL=dot(n,Ls);float NoV=dot(n,inputV);
float LoV=dot (Ls,inputV);
vec3 H=(inputV+Ls)*0.5;float VoH=dot(inputV,H);
vec3 Ls=hemisphereCosSample(Xi);Ls=normalize(Ls);float NoL=Ls.z;
vec3 V=tbnInverse*inputV;float NoV=V.z;
float LoV=dot (Ls,V);
vec3 H=(V+Ls)*0.5;float VoH=dot(V,H);
if (NoL>0.) {
float pdf=texture2D(icdfSampler,T).z;vec3 c=textureCubeLodEXT(inputTexture,Ls,0.).rgb;
float pdf_inversed=PI/NoL;float omegaS=NUM_SAMPLES_FLOAT_INVERSED*pdf_inversed;float l=log4(omegaS)-log4(omegaP)+log4(K);float mipLevel=clamp(l,0.,maxLevel);
CUSTOM_IRRADIANCE_FILTERING_FUNCTION
vec3 c=textureCubeLodEXT(inputTexture,tbn*Ls,mipLevel).rgb;
c=toLinearSpace(c);
vec3 diffuseRoughnessTerm=vec3(1.0);
diffuseRoughnessTerm=diffuseBRDF_EON(clampedAlbedo,diffuseRoughness,NoL,NoV,LoV)*PI;
diffuseRoughnessTerm=vec3(diffuseBRDF_Burley(NoL,NoV,VoH,diffuseRoughness)*PI);
vec3 light=pdf<1e-6 ? vec3(0.0) : vec3(1.0)/vec3(pdf)*c;result+=NoL*diffuseRoughnessTerm*light;
result+=c*diffuseRoughnessTerm;
}}
result=result*NUM_SAMPLES_FLOAT_INVERSED;
result=result/clampedAlbedo;
return result;}
vec3 radiance(float alphaG,samplerCube inputTexture,vec3 inputN,vec2 filteringInfo)
{vec3 n=normalize(inputN);vec3 c=textureCubeLodEXT(inputTexture,n,0.).rgb;
if (alphaG==0.) {
c=toLinearSpace(c);
return c;} else {vec3 result=vec3(0.);vec3 tangent=abs(n.z)<0.999 ? vec3(0.,0.,1.) : vec3(1.,0.,0.);tangent=normalize(cross(tangent,n));vec3 bitangent=cross(n,tangent);mat3 tbn=mat3(tangent,bitangent,n);float maxLevel=filteringInfo.y;float dim0=filteringInfo.x;float omegaP=(4.*PI)/(6.*dim0*dim0);float weight=0.;
for(uint i=0u; i<NUM_SAMPLES; ++i)
for(int i=0; i<NUM_SAMPLES; ++i)
{vec2 Xi=hammersley(i,NUM_SAMPLES);vec3 H=hemisphereImportanceSampleDggx(Xi,alphaG);float NoV=1.;float NoH=H.z;float NoH2=H.z*H.z;float NoL=2.*NoH2-1.;vec3 L=vec3(2.*NoH*H.x,2.*NoH*H.y,NoL);L=normalize(L);if (NoL>0.) {float pdf_inversed=4./normalDistributionFunction_TrowbridgeReitzGGX(NoH,alphaG);float omegaS=NUM_SAMPLES_FLOAT_INVERSED*pdf_inversed;float l=log4(omegaS)-log4(omegaP)+log4(K);float mipLevel=clamp(float(l),0.0,maxLevel);weight+=NoL;vec3 c=textureCubeLodEXT(inputTexture,tbn*L,mipLevel).rgb;
c=toLinearSpace(c);
result+=c*NoL;}}
result=result/weight;return result;}}
vec3 radianceAnisotropic(
float alphaTangent,
float alphaBitangent,
samplerCube inputTexture,
vec3 inputView,
vec3 inputTangent,
vec3 inputBitangent,
vec3 inputNormal,
vec2 filteringInfo,
vec2 noiseInput,
bool isRefraction,
float ior
)
{vec3 V=inputView;vec3 N=inputNormal;vec3 T=inputTangent;vec3 B=inputBitangent;vec3 result=vec3(0.);float maxLevel=filteringInfo.y;float dim0=filteringInfo.x;float clampedAlphaT=max(alphaTangent,MINIMUMVARIANCE);float clampedAlphaB=max(alphaBitangent,MINIMUMVARIANCE);float effectiveDim=dim0*sqrt(clampedAlphaT*clampedAlphaB);float omegaP=(4.*PI)/(6.*effectiveDim*effectiveDim);const float noiseScale=clamp(log2(float(NUM_SAMPLES))/12.0f,0.0f,1.0f);float weight=0.;
for(uint i=0u; i<NUM_SAMPLES; ++i)
for(int i=0; i<NUM_SAMPLES; ++i)
{vec2 Xi=hammersley(i,NUM_SAMPLES);Xi=fract(Xi+noiseInput*mix(0.5f,0.015f,noiseScale));
vec3 H_tangent=hemisphereImportanceSampleDggxAnisotropic(Xi,clampedAlphaT,clampedAlphaB);vec3 H=normalize(H_tangent.x*T+H_tangent.y*B+H_tangent.z*N);vec3 L;if (isRefraction) {L=refract(-V,H,1.0/ior);} else {L=reflect(-V,H);}
float NoH=max(dot(N,H),0.001);float VoH=max(dot(V,H),0.001);float NoL=max(dot(N,L),0.001);if (NoL>0.) {float pdf_inversed=4./normalDistributionFunction_BurleyGGX_Anisotropic(
H_tangent.z,H_tangent.x,H_tangent.y,vec2(clampedAlphaT,clampedAlphaB)
);float omegaS=NUM_SAMPLES_FLOAT_INVERSED*pdf_inversed;float l=log4(omegaS)-log4(omegaP)+log4(K);float mipLevel=clamp(float(l),0.0,maxLevel);weight+=NoL;vec3 c=textureCubeLodEXT(inputTexture,L,mipLevel).rgb;
c=toLinearSpace(c);
result+=c*NoL;}}
result=result/weight;return result;}
`;
// Sideeffect
if (!ShaderStore.IncludesShadersStore[name]) {
ShaderStore.IncludesShadersStore[name] = shader;
}
/** @internal */
const hdrFilteringFunctions = { name, shader };
export { hdrFilteringFunctions as h, importanceSampling as i };
//# sourceMappingURL=hdrFilteringFunctions-FqTqoCZG.esm.js.map