@babylonjs/core/ShadersWGSL/ShadersInclude/ltcHelperFunctions.js

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// Do not edit.
import { ShaderStore } from "../../Engines/shaderStore.js";
const name = "ltcHelperFunctions";
const shader = `fn LTCUv(N: vec3f,V: vec3f,roughness: f32)->vec2f {var LUTSIZE: f32=64.0;var LUTSCALE: f32=( LUTSIZE-1.0 )/LUTSIZE;var LUTBIAS:f32=0.5/LUTSIZE;var dotNV:f32=saturate( dot( N,V ) );var uv:vec2f=vec2f( roughness,sqrt( 1.0-dotNV ) );uv=uv*LUTSCALE+LUTBIAS;return uv;}
fn LTCClippedSphereFormFactor( f:vec3f )->f32 {var l: f32=length( f );return max( ( l*l+f.z )/( l+1.0 ),0.0 );}
fn LTCEdgeVectorFormFactor( v1:vec3f,v2:vec3f )->vec3f {var x:f32=dot( v1,v2 );var y:f32=abs( x );var a:f32=0.8543985+( 0.4965155+0.0145206*y )*y;var b:f32=3.4175940+( 4.1616724+y )*y;var v:f32=a/b;var thetaSintheta:f32=0.0;if( x>0.0 )
{thetaSintheta=v;}
else
{thetaSintheta=0.5*inverseSqrt( max( 1.0-x*x,0.00000001 ) )-v;}
return cross( v1,v2 )*thetaSintheta;}
fn LTCEvaluate( N:vec3f,V:vec3f,P:vec3f,mInv: mat3x3<f32>,rectCoords0:vec3f,rectCoords1:vec3f,rectCoords2:vec3f,rectCoords3:vec3f )->vec3f {var v1:vec3f=rectCoords1-rectCoords0;var v2:vec3f=rectCoords3-rectCoords0;var lightNormal:vec3f=cross( v1,v2 );if( dot( lightNormal,P-rectCoords0 )<0.0 ){return vec3f( 0.0 );}
var T1:vec3f=normalize( V-N*dot( V,N ) );var T2:vec3f=- cross( N,T1 ); 
var mat: mat3x3<f32>=mInv*transposeMat3( mat3x3<f32>( T1,T2,N ) );var coords0: vec3f=mat*( rectCoords0-P );var coords1: vec3f=mat*( rectCoords1-P );var coords2: vec3f=mat*( rectCoords2-P );var coords3: vec3f=mat*( rectCoords3-P );coords0=normalize( coords0 );coords1=normalize( coords1 );coords2=normalize( coords2 );coords3=normalize( coords3 );var vectorFormFactor:vec3f=vec3( 0.0 );vectorFormFactor+=LTCEdgeVectorFormFactor( coords0,coords1 );vectorFormFactor+=LTCEdgeVectorFormFactor( coords1,coords2 );vectorFormFactor+=LTCEdgeVectorFormFactor( coords2,coords3 );vectorFormFactor+=LTCEdgeVectorFormFactor( coords3,coords0 );var result:f32=LTCClippedSphereFormFactor( vectorFormFactor );return vec3f( result );}
struct areaLightData
{Diffuse: vec3f,
Specular: vec3f,
Fresnel: vec4f};fn computeAreaLightSpecularDiffuseFresnel(ltc1: texture_2d<f32>,ltc1Sampler:sampler,ltc2:texture_2d<f32>,ltc2Sampler:sampler,viewDir: vec3f,normal:vec3f,position:vec3f,lightPos:vec3f,halfWidth:vec3f, halfHeight:vec3f,roughness:f32)->areaLightData {var result: areaLightData;var rectCoords0:vec3f=lightPos+halfWidth-halfHeight; 
var rectCoords1:vec3f=lightPos-halfWidth-halfHeight;var rectCoords2:vec3f=lightPos-halfWidth+halfHeight;var rectCoords3:vec3f=lightPos+halfWidth+halfHeight;
#ifdef SPECULARTERM
var uv:vec2f=LTCUv( normal,viewDir,roughness );var t1:vec4f=textureSample( ltc1,ltc1Sampler,uv );var t2:vec4f=textureSample( ltc2,ltc2Sampler,uv );var mInv:mat3x3<f32>=mat3x3<f32>(
vec3f( t1.x,0,t1.y ),
vec3f( 0,1, 0 ),
vec3f( t1.z,0,t1.w )
);result.Fresnel=t2;result.Specular=LTCEvaluate( normal,viewDir,position,mInv,rectCoords0,rectCoords1,rectCoords2,rectCoords3 );
#endif
var mInvEmpty:mat3x3<f32>=mat3x3<f32>(
vec3f( 1,0,0 ),
vec3f( 0,1,0 ),
vec3f( 0,0,1 )
);result.Diffuse+=LTCEvaluate( normal,viewDir,position,mInvEmpty,rectCoords0,rectCoords1,rectCoords2,rectCoords3 );return result;}
fn FetchDiffuseFilteredTexture(texLightFiltered: texture_2d<f32>,texLightFilteredSampler: sampler,p1_: vec3f,p2_: vec3f,p3_: vec3f,p4_: vec3f)->vec3f {var V1: vec3f=p2_-p1_;var V2: vec3f=p4_-p1_;var planeOrtho: vec3f=cross(V1,V2);var planeAreaSquared: f32=dot(planeOrtho,planeOrtho);var planeDistxPlaneArea: f32=dot(planeOrtho,p1_);var P: vec3f=planeDistxPlaneArea*planeOrtho/planeAreaSquared-p1_;var dot_V1_V2: f32=dot(V1,V2);var inv_dot_V1_V1: f32=1.0/dot(V1,V1);var V2_: vec3f=V2-V1*dot_V1_V2*inv_dot_V1_V1;var Puv: vec2f;Puv.y=dot(V2_,P)/dot(V2_,V2_);Puv.x=dot(V1,P)*inv_dot_V1_V1-dot_V1_V2*inv_dot_V1_V1*Puv.y;var d: f32=abs(planeDistxPlaneArea)/pow(planeAreaSquared,0.75);var sampleLOD: f32=log(2048.0*d)/log(3.0);var sampleUV: vec2f=vec2f(0.125,0.125)+(vec2f(0.75)*Puv);sampleUV.x=1.0-sampleUV.x;return textureSampleLevel(texLightFiltered,texLightFilteredSampler,sampleUV,sampleLOD).rgb;}
fn LTCEvaluateWithEmission(N: vec3f,V: vec3f,P: vec3f,mInv: mat3x3<f32>,rectCoords0: vec3f,rectCoords1: vec3f,rectCoords2: vec3f,rectCoords3: vec3f,texFilteredMap: texture_2d<f32>,texFilteredMapSampler: sampler)->vec3f {var v1: vec3f=rectCoords1-rectCoords0;var v2: vec3f=rectCoords3-rectCoords0;var lightNormal: vec3f=cross(v1,v2);if (dot(lightNormal,P-rectCoords0)<0.0) {return vec3f(0.0);}
var T1: vec3f=normalize(V-N*dot(V,N));var T2: vec3f=-cross(N,T1);var mat: mat3x3<f32>=mInv*transposeMat3(mat3x3<f32>(T1,T2,N));var coords0: vec3f=mat*(rectCoords0-P);var coords1: vec3f=mat*(rectCoords1-P);var coords2: vec3f=mat*(rectCoords2-P);var coords3: vec3f=mat*(rectCoords3-P);var textureLight: vec3f=FetchDiffuseFilteredTexture(texFilteredMap,texFilteredMapSampler,coords0,coords1,coords2,coords3);coords0=normalize(coords0);coords1=normalize(coords1);coords2=normalize(coords2);coords3=normalize(coords3);var vectorFormFactor: vec3f=vec3f(0.0);vectorFormFactor+=LTCEdgeVectorFormFactor(coords0,coords1);vectorFormFactor+=LTCEdgeVectorFormFactor(coords1,coords2);vectorFormFactor+=LTCEdgeVectorFormFactor(coords2,coords3);vectorFormFactor+=LTCEdgeVectorFormFactor(coords3,coords0);var result: f32=LTCClippedSphereFormFactor(vectorFormFactor);return vec3f(result)*textureLight;}
fn computeAreaLightSpecularDiffuseFresnelWithEmission(ltc1: texture_2d<f32>,ltc1Sampler:sampler,ltc2:texture_2d<f32>,ltc2Sampler:sampler,emissionTexture: texture_2d<f32>,emissionTextureSampler:sampler,viewDir: vec3f,normal:vec3f,position:vec3f,lightPos:vec3f,halfWidth:vec3f, halfHeight:vec3f,roughness:f32)->areaLightData {var result: areaLightData;var rectCoords0: vec3f=lightPos+halfWidth-halfHeight; 
var rectCoords1: vec3f=lightPos-halfWidth-halfHeight;var rectCoords2: vec3f=lightPos-halfWidth+halfHeight;var rectCoords3: vec3f=lightPos+halfWidth+halfHeight;
#ifdef SPECULARTERM
var uv: vec2f=LTCUv(normal,viewDir,roughness);var t1: vec4f=textureSample(ltc1,ltc1Sampler,uv);var t2: vec4f=textureSample(ltc2,ltc2Sampler,uv);var mInv: mat3x3<f32>=mat3x3<f32>(
vec3f(t1.x,0,t1.y),
vec3f(0,1,0),
vec3f(t1.z,0,t1.w)
);result.Specular=LTCEvaluateWithEmission(normal,viewDir,position,mInv,rectCoords0,rectCoords1,rectCoords2,rectCoords3,emissionTexture,emissionTextureSampler);result.Fresnel=t2;
#endif
var mInvEmpty: mat3x3<f32>=mat3x3<f32>(
vec3f(1,0,0),
vec3f(0,1,0),
vec3f(0,0,1)
);result.Diffuse=LTCEvaluateWithEmission(normal,viewDir,position,mInvEmpty,rectCoords0,rectCoords1,rectCoords2,rectCoords3,emissionTexture,emissionTextureSampler);return result;}
`;
// Sideeffect
if (!ShaderStore.IncludesShadersStoreWGSL[name]) {
    ShaderStore.IncludesShadersStoreWGSL[name] = shader;
}
/** @internal */
export const ltcHelperFunctionsWGSL = { name, shader };
//# sourceMappingURL=ltcHelperFunctions.js.map