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

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// Do not edit.
import { ShaderStore } from "../../Engines/shaderStore.js";
const name = "ltcHelperFunctions";
const shader = `vec2 LTCUv( const in vec3 N,const in vec3 V,const in float roughness ) {const float LUTSIZE=64.0;const float LUTSCALE=( LUTSIZE-1.0 )/LUTSIZE;const float LUTBIAS=0.5/LUTSIZE;float dotNV=saturate( dot( N,V ) );vec2 uv=vec2( roughness,sqrt( 1.0-dotNV ) );uv=uv*LUTSCALE+LUTBIAS;return uv;}
float LTCClippedSphereFormFactor( const in vec3 f ) {float l=length( f );return max( ( l*l+f.z )/( l+1.0 ),0.0 );}
vec3 LTCEdgeVectorFormFactor( const in vec3 v1,const in vec3 v2 ) {float x=dot( v1,v2 );float y=abs( x );float a=0.8543985+( 0.4965155+0.0145206*y )*y;float b=3.4175940+( 4.1616724+y )*y;float v=a/b;float thetaSintheta=0.0;if( x>0.0 )
{thetaSintheta=v;}
else
{thetaSintheta=0.5*inversesqrt( max( 1.0-x*x,1e-7 ) )-v;}
return cross( v1,v2 )*thetaSintheta;}
vec3 LTCEvaluate( const in vec3 N,const in vec3 V,const in vec3 P,const in mat3 mInv,const in vec3 rectCoords[ 4 ] ) {vec3 v1=rectCoords[ 1 ]-rectCoords[ 0 ];vec3 v2=rectCoords[ 3 ]-rectCoords[ 0 ];vec3 lightNormal=cross( v1,v2 );if( dot( lightNormal,P-rectCoords[ 0 ] )<0.0 ) return vec3( 0.0 );vec3 T1,T2;T1=normalize( V-N*dot( V,N ) );T2=- cross( N,T1 ); 
mat3 mat=mInv*transposeMat3( mat3( T1,T2,N ) );vec3 coords[ 4 ];coords[ 0 ]=mat*( rectCoords[ 0 ]-P );coords[ 1 ]=mat*( rectCoords[ 1 ]-P );coords[ 2 ]=mat*( rectCoords[ 2 ]-P );coords[ 3 ]=mat*( rectCoords[ 3 ]-P );coords[ 0 ]=normalize( coords[ 0 ] );coords[ 1 ]=normalize( coords[ 1 ] );coords[ 2 ]=normalize( coords[ 2 ] );coords[ 3 ]=normalize( coords[ 3 ] );vec3 vectorFormFactor=vec3( 0.0 );vectorFormFactor+=LTCEdgeVectorFormFactor( coords[ 0 ],coords[ 1 ] );vectorFormFactor+=LTCEdgeVectorFormFactor( coords[ 1 ],coords[ 2 ] );vectorFormFactor+=LTCEdgeVectorFormFactor( coords[ 2 ],coords[ 3 ] );vectorFormFactor+=LTCEdgeVectorFormFactor( coords[ 3 ],coords[ 0 ] );float result=LTCClippedSphereFormFactor( vectorFormFactor );return vec3( result );}
struct areaLightData
{vec3 Diffuse;vec3 Specular;vec4 Fresnel;};
#define inline
areaLightData computeAreaLightSpecularDiffuseFresnel(const in sampler2D ltc1,const in sampler2D ltc2,const in vec3 viewDir,const in vec3 normal,const in vec3 position,const in vec3 lightPos,const in vec3 halfWidth,const in vec3 halfHeight,const in float roughness) 
{areaLightData result;vec3 rectCoords[ 4 ];rectCoords[ 0 ]=lightPos+halfWidth-halfHeight; 
rectCoords[ 1 ]=lightPos-halfWidth-halfHeight;rectCoords[ 2 ]=lightPos-halfWidth+halfHeight;rectCoords[ 3 ]=lightPos+halfWidth+halfHeight;
#ifdef SPECULARTERM
vec2 uv=LTCUv( normal,viewDir,roughness );vec4 t1=texture2D( ltc1,uv );vec4 t2=texture2D( ltc2,uv );mat3 mInv=mat3(
vec3( t1.x,0,t1.y ),
vec3( 0,1, 0 ),
vec3( t1.z,0,t1.w )
);result.Specular=LTCEvaluate( normal,viewDir,position,mInv,rectCoords );result.Fresnel=t2;
#endif
result.Diffuse=LTCEvaluate( normal,viewDir,position,mat3( 1.0 ),rectCoords );return result;}`;
// Sideeffect
if (!ShaderStore.IncludesShadersStore[name]) {
    ShaderStore.IncludesShadersStore[name] = shader;
}
/** @internal */
export const ltcHelperFunctions = { name, shader };
//# sourceMappingURL=ltcHelperFunctions.js.map