Doodle3D-Slicer/three.js-master/examples/js/ShaderSkin.js
2015-06-12 15:58:26 +02:00

803 lines
21 KiB
JavaScript
Executable File

/**
* @author alteredq / http://alteredqualia.com/
*
*/
THREE.ShaderSkin = {
/* ------------------------------------------------------------------------------------------
// Simple skin shader
// - per-pixel Blinn-Phong diffuse term mixed with half-Lambert wrap-around term (per color component)
// - physically based specular term (Kelemen/Szirmay-Kalos specular reflectance)
//
// - diffuse map
// - bump map
// - specular map
// - point, directional and hemisphere lights (use with "lights: true" material option)
// - fog (use with "fog: true" material option)
// - shadow maps
//
// ------------------------------------------------------------------------------------------ */
'skinSimple' : {
uniforms: THREE.UniformsUtils.merge( [
THREE.UniformsLib[ "fog" ],
THREE.UniformsLib[ "lights" ],
THREE.UniformsLib[ "shadowmap" ],
{
"enableBump" : { type: "i", value: 0 },
"enableSpecular": { type: "i", value: 0 },
"tDiffuse" : { type: "t", value: null },
"tBeckmann" : { type: "t", value: null },
"diffuse": { type: "c", value: new THREE.Color( 0xeeeeee ) },
"specular": { type: "c", value: new THREE.Color( 0x111111 ) },
"opacity": { type: "f", value: 1 },
"uRoughness": { type: "f", value: 0.15 },
"uSpecularBrightness": { type: "f", value: 0.75 },
"bumpMap" : { type: "t", value: null },
"bumpScale" : { type: "f", value: 1 },
"specularMap" : { type: "t", value: null },
"offsetRepeat" : { type: "v4", value: new THREE.Vector4( 0, 0, 1, 1 ) },
"uWrapRGB": { type: "v3", value: new THREE.Vector3( 0.75, 0.375, 0.1875 ) }
}
] ),
fragmentShader: [
"#define USE_BUMPMAP",
"#extension GL_OES_standard_derivatives : enable",
"uniform bool enableBump;",
"uniform bool enableSpecular;",
"uniform vec3 diffuse;",
"uniform vec3 specular;",
"uniform float opacity;",
"uniform float uRoughness;",
"uniform float uSpecularBrightness;",
"uniform vec3 uWrapRGB;",
"uniform sampler2D tDiffuse;",
"uniform sampler2D tBeckmann;",
"uniform sampler2D specularMap;",
"varying vec3 vNormal;",
"varying vec2 vUv;",
"uniform vec3 ambientLightColor;",
"#if MAX_DIR_LIGHTS > 0",
"uniform vec3 directionalLightColor[ MAX_DIR_LIGHTS ];",
"uniform vec3 directionalLightDirection[ MAX_DIR_LIGHTS ];",
"#endif",
"#if MAX_HEMI_LIGHTS > 0",
"uniform vec3 hemisphereLightSkyColor[ MAX_HEMI_LIGHTS ];",
"uniform vec3 hemisphereLightGroundColor[ MAX_HEMI_LIGHTS ];",
"uniform vec3 hemisphereLightDirection[ MAX_HEMI_LIGHTS ];",
"#endif",
"#if MAX_POINT_LIGHTS > 0",
"uniform vec3 pointLightColor[ MAX_POINT_LIGHTS ];",
"uniform vec3 pointLightPosition[ MAX_POINT_LIGHTS ];",
"uniform float pointLightDistance[ MAX_POINT_LIGHTS ];",
"uniform float pointLightDecay[ MAX_POINT_LIGHTS ];",
"#endif",
"varying vec3 vViewPosition;",
THREE.ShaderChunk[ "common" ],
THREE.ShaderChunk[ "shadowmap_pars_fragment" ],
THREE.ShaderChunk[ "fog_pars_fragment" ],
THREE.ShaderChunk[ "bumpmap_pars_fragment" ],
// Fresnel term
"float fresnelReflectance( vec3 H, vec3 V, float F0 ) {",
"float base = 1.0 - dot( V, H );",
"float exponential = pow( base, 5.0 );",
"return exponential + F0 * ( 1.0 - exponential );",
"}",
// Kelemen/Szirmay-Kalos specular BRDF
"float KS_Skin_Specular( vec3 N,", // Bumped surface normal
"vec3 L,", // Points to light
"vec3 V,", // Points to eye
"float m,", // Roughness
"float rho_s", // Specular brightness
") {",
"float result = 0.0;",
"float ndotl = dot( N, L );",
"if( ndotl > 0.0 ) {",
"vec3 h = L + V;", // Unnormalized half-way vector
"vec3 H = normalize( h );",
"float ndoth = dot( N, H );",
"float PH = pow( 2.0 * texture2D( tBeckmann, vec2( ndoth, m ) ).x, 10.0 );",
"float F = fresnelReflectance( H, V, 0.028 );",
"float frSpec = max( PH * F / dot( h, h ), 0.0 );",
"result = ndotl * rho_s * frSpec;", // BRDF * dot(N,L) * rho_s
"}",
"return result;",
"}",
"void main() {",
"vec3 outgoingLight = vec3( 0.0 );", // outgoing light does not have an alpha, the surface does
"vec4 diffuseColor = vec4( diffuse, opacity );",
"vec4 colDiffuse = texture2D( tDiffuse, vUv );",
"colDiffuse.rgb *= colDiffuse.rgb;",
"diffuseColor = diffuseColor * colDiffuse;",
"vec3 normal = normalize( vNormal );",
"vec3 viewPosition = normalize( vViewPosition );",
"float specularStrength;",
"if ( enableSpecular ) {",
"vec4 texelSpecular = texture2D( specularMap, vUv );",
"specularStrength = texelSpecular.r;",
"} else {",
"specularStrength = 1.0;",
"}",
"#ifdef USE_BUMPMAP",
"if ( enableBump ) normal = perturbNormalArb( -vViewPosition, normal, dHdxy_fwd() );",
"#endif",
// point lights
"vec3 totalSpecularLight = vec3( 0.0 );",
"vec3 totalDiffuseLight = vec3( 0.0 );",
"#if MAX_POINT_LIGHTS > 0",
"for ( int i = 0; i < MAX_POINT_LIGHTS; i ++ ) {",
"vec4 lPosition = viewMatrix * vec4( pointLightPosition[ i ], 1.0 );",
"vec3 lVector = lPosition.xyz + vViewPosition.xyz;",
"float attenuation = calcLightAttenuation( length( lVector ), pointLightDistance[ i ], pointLightDecay[i] );",
"lVector = normalize( lVector );",
"float pointDiffuseWeightFull = max( dot( normal, lVector ), 0.0 );",
"float pointDiffuseWeightHalf = max( 0.5 * dot( normal, lVector ) + 0.5, 0.0 );",
"vec3 pointDiffuseWeight = mix( vec3 ( pointDiffuseWeightFull ), vec3( pointDiffuseWeightHalf ), uWrapRGB );",
"float pointSpecularWeight = KS_Skin_Specular( normal, lVector, viewPosition, uRoughness, uSpecularBrightness );",
"totalDiffuseLight += attenuation * pointLightColor[ i ] * pointDiffuseWeight;",
"totalSpecularLight += attenuation * specular * pointLightColor[ i ] * pointSpecularWeight * specularStrength;",
"}",
"#endif",
// directional lights
"#if MAX_DIR_LIGHTS > 0",
"for( int i = 0; i < MAX_DIR_LIGHTS; i++ ) {",
"vec3 dirVector = transformDirection( directionalLightDirection[ i ], viewMatrix );",
"float dirDiffuseWeightFull = max( dot( normal, dirVector ), 0.0 );",
"float dirDiffuseWeightHalf = max( 0.5 * dot( normal, dirVector ) + 0.5, 0.0 );",
"vec3 dirDiffuseWeight = mix( vec3 ( dirDiffuseWeightFull ), vec3( dirDiffuseWeightHalf ), uWrapRGB );",
"float dirSpecularWeight = KS_Skin_Specular( normal, dirVector, viewPosition, uRoughness, uSpecularBrightness );",
"totalDiffuseLight += directionalLightColor[ i ] * dirDiffuseWeight;",
"totalSpecularLight += specular * directionalLightColor[ i ] * dirSpecularWeight * specularStrength;",
"}",
"#endif",
// hemisphere lights
"#if MAX_HEMI_LIGHTS > 0",
"for ( int i = 0; i < MAX_HEMI_LIGHTS; i ++ ) {",
"vec3 lVector = transformDirection( hemisphereLightDirection[ i ], viewMatrix );",
"float dotProduct = dot( normal, lVector );",
"float hemiDiffuseWeight = 0.5 * dotProduct + 0.5;",
"totalDiffuseLight += mix( hemisphereLightGroundColor[ i ], hemisphereLightSkyColor[ i ], hemiDiffuseWeight );",
// specular (sky light)
"float hemiSpecularWeight = 0.0;",
"hemiSpecularWeight += KS_Skin_Specular( normal, lVector, viewPosition, uRoughness, uSpecularBrightness );",
// specular (ground light)
"vec3 lVectorGround = -lVector;",
"hemiSpecularWeight += KS_Skin_Specular( normal, lVectorGround, viewPosition, uRoughness, uSpecularBrightness );",
"totalSpecularLight += specular * mix( hemisphereLightGroundColor[ i ], hemisphereLightSkyColor[ i ], hemiDiffuseWeight ) * hemiSpecularWeight * specularStrength;",
"}",
"#endif",
"outgoingLight += diffuseColor.xyz * ( totalDiffuseLight + ambientLightColor * diffuse ) + totalSpecularLight;",
THREE.ShaderChunk[ "shadowmap_fragment" ],
THREE.ShaderChunk[ "linear_to_gamma_fragment" ],
THREE.ShaderChunk[ "fog_fragment" ],
"gl_FragColor = vec4( outgoingLight, diffuseColor.a );", // TODO, this should be pre-multiplied to allow for bright highlights on very transparent objects
"}"
].join("\n"),
vertexShader: [
"uniform vec4 offsetRepeat;",
"varying vec3 vNormal;",
"varying vec2 vUv;",
"varying vec3 vViewPosition;",
THREE.ShaderChunk[ "common" ],
THREE.ShaderChunk[ "shadowmap_pars_vertex" ],
"void main() {",
"vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );",
"vec4 worldPosition = modelMatrix * vec4( position, 1.0 );",
"vViewPosition = -mvPosition.xyz;",
"vNormal = normalize( normalMatrix * normal );",
"vUv = uv * offsetRepeat.zw + offsetRepeat.xy;",
"gl_Position = projectionMatrix * mvPosition;",
THREE.ShaderChunk[ "shadowmap_vertex" ],
"}"
].join( "\n" )
},
/* ------------------------------------------------------------------------------------------
// Skin shader
// - Blinn-Phong diffuse term (using normal + diffuse maps)
// - subsurface scattering approximation by four blur layers
// - physically based specular term (Kelemen/Szirmay-Kalos specular reflectance)
//
// - point and directional lights (use with "lights: true" material option)
//
// - based on Nvidia Advanced Skin Rendering GDC 2007 presentation
// and GPU Gems 3 Chapter 14. Advanced Techniques for Realistic Real-Time Skin Rendering
//
// http://developer.download.nvidia.com/presentations/2007/gdc/Advanced_Skin.pdf
// http://http.developer.nvidia.com/GPUGems3/gpugems3_ch14.html
// ------------------------------------------------------------------------------------------ */
'skin' : {
uniforms: THREE.UniformsUtils.merge( [
THREE.UniformsLib[ "fog" ],
THREE.UniformsLib[ "lights" ],
{
"passID": { type: "i", value: 0 },
"tDiffuse" : { type: "t", value: null },
"tNormal" : { type: "t", value: null },
"tBlur1" : { type: "t", value: null },
"tBlur2" : { type: "t", value: null },
"tBlur3" : { type: "t", value: null },
"tBlur4" : { type: "t", value: null },
"tBeckmann" : { type: "t", value: null },
"uNormalScale": { type: "f", value: 1.0 },
"diffuse": { type: "c", value: new THREE.Color( 0xeeeeee ) },
"specular": { type: "c", value: new THREE.Color( 0x111111 ) },
"opacity": { type: "f", value: 1 },
"uRoughness": { type: "f", value: 0.15 },
"uSpecularBrightness": { type: "f", value: 0.75 }
}
] ),
fragmentShader: [
"uniform vec3 diffuse;",
"uniform vec3 specular;",
"uniform float opacity;",
"uniform float uRoughness;",
"uniform float uSpecularBrightness;",
"uniform int passID;",
"uniform sampler2D tDiffuse;",
"uniform sampler2D tNormal;",
"uniform sampler2D tBlur1;",
"uniform sampler2D tBlur2;",
"uniform sampler2D tBlur3;",
"uniform sampler2D tBlur4;",
"uniform sampler2D tBeckmann;",
"uniform float uNormalScale;",
"varying vec3 vTangent;",
"varying vec3 vBinormal;",
"varying vec3 vNormal;",
"varying vec2 vUv;",
"uniform vec3 ambientLightColor;",
"#if MAX_DIR_LIGHTS > 0",
"uniform vec3 directionalLightColor[ MAX_DIR_LIGHTS ];",
"uniform vec3 directionalLightDirection[ MAX_DIR_LIGHTS ];",
"#endif",
"#if MAX_POINT_LIGHTS > 0",
"uniform vec3 pointLightColor[ MAX_POINT_LIGHTS ];",
"varying vec4 vPointLight[ MAX_POINT_LIGHTS ];",
"#endif",
"varying vec3 vViewPosition;",
THREE.ShaderChunk[ "common" ],
THREE.ShaderChunk[ "fog_pars_fragment" ],
"float fresnelReflectance( vec3 H, vec3 V, float F0 ) {",
"float base = 1.0 - dot( V, H );",
"float exponential = pow( base, 5.0 );",
"return exponential + F0 * ( 1.0 - exponential );",
"}",
// Kelemen/Szirmay-Kalos specular BRDF
"float KS_Skin_Specular( vec3 N,", // Bumped surface normal
"vec3 L,", // Points to light
"vec3 V,", // Points to eye
"float m,", // Roughness
"float rho_s", // Specular brightness
") {",
"float result = 0.0;",
"float ndotl = dot( N, L );",
"if( ndotl > 0.0 ) {",
"vec3 h = L + V;", // Unnormalized half-way vector
"vec3 H = normalize( h );",
"float ndoth = dot( N, H );",
"float PH = pow( 2.0 * texture2D( tBeckmann, vec2( ndoth, m ) ).x, 10.0 );",
"float F = fresnelReflectance( H, V, 0.028 );",
"float frSpec = max( PH * F / dot( h, h ), 0.0 );",
"result = ndotl * rho_s * frSpec;", // BRDF * dot(N,L) * rho_s
"}",
"return result;",
"}",
"void main() {",
"vec3 outgoingLight = vec3( 0.0 );", // outgoing light does not have an alpha, the surface does
"vec4 diffuseColor = vec4( diffuse, opacity );",
"vec4 mSpecular = vec4( specular, opacity );",
"vec3 normalTex = texture2D( tNormal, vUv ).xyz * 2.0 - 1.0;",
"normalTex.xy *= uNormalScale;",
"normalTex = normalize( normalTex );",
"vec4 colDiffuse = texture2D( tDiffuse, vUv );",
"colDiffuse *= colDiffuse;",
"diffuseColor *= colDiffuse;",
"mat3 tsb = mat3( vTangent, vBinormal, vNormal );",
"vec3 finalNormal = tsb * normalTex;",
"vec3 normal = normalize( finalNormal );",
"vec3 viewPosition = normalize( vViewPosition );",
// point lights
"vec3 totalDiffuseLight = vec3( 0.0 );",
"vec3 totalSpecularLight = vec3( 0.0 );",
"#if MAX_POINT_LIGHTS > 0",
"for ( int i = 0; i < MAX_POINT_LIGHTS; i ++ ) {",
"vec3 pointVector = normalize( vPointLight[ i ].xyz );",
"float pointDistance = vPointLight[ i ].w;",
"float pointDiffuseWeight = max( dot( normal, pointVector ), 0.0 );",
"totalDiffuseLight += pointDistance * pointLightColor[ i ] * pointDiffuseWeight;",
"if ( passID == 1 )",
"totalSpecularLight += pointDistance * mSpecular.xyz * pointLightColor[ i ] * KS_Skin_Specular( normal, pointVector, viewPosition, uRoughness, uSpecularBrightness );",
"}",
"#endif",
// directional lights
"#if MAX_DIR_LIGHTS > 0",
"for( int i = 0; i < MAX_DIR_LIGHTS; i++ ) {",
"vec3 dirVector = transformDirection( directionalLightDirection[ i ], viewMatrix );",
"float dirDiffuseWeight = max( dot( normal, dirVector ), 0.0 );",
"totalDiffuseLight += directionalLightColor[ i ] * dirDiffuseWeight;",
"if ( passID == 1 )",
"totalSpecularLight += mSpecular.xyz * directionalLightColor[ i ] * KS_Skin_Specular( normal, dirVector, viewPosition, uRoughness, uSpecularBrightness );",
"}",
"#endif",
"outgoingLight += diffuseColor.rgb * ( totalDiffuseLight + totalSpecularLight );",
"if ( passID == 0 ) {",
"outgoingLight = sqrt( outgoingLight );",
"} else if ( passID == 1 ) {",
//"#define VERSION1",
"#ifdef VERSION1",
"vec3 nonblurColor = sqrt(outgoingLight );",
"#else",
"vec3 nonblurColor = outgoingLight;",
"#endif",
"vec3 blur1Color = texture2D( tBlur1, vUv ).xyz;",
"vec3 blur2Color = texture2D( tBlur2, vUv ).xyz;",
"vec3 blur3Color = texture2D( tBlur3, vUv ).xyz;",
"vec3 blur4Color = texture2D( tBlur4, vUv ).xyz;",
//"gl_FragColor = vec4( blur1Color, gl_FragColor.w );",
//"gl_FragColor = vec4( vec3( 0.22, 0.5, 0.7 ) * nonblurColor + vec3( 0.2, 0.5, 0.3 ) * blur1Color + vec3( 0.58, 0.0, 0.0 ) * blur2Color, gl_FragColor.w );",
//"gl_FragColor = vec4( vec3( 0.25, 0.6, 0.8 ) * nonblurColor + vec3( 0.15, 0.25, 0.2 ) * blur1Color + vec3( 0.15, 0.15, 0.0 ) * blur2Color + vec3( 0.45, 0.0, 0.0 ) * blur3Color, gl_FragColor.w );",
"outgoingLight = vec3( vec3( 0.22, 0.437, 0.635 ) * nonblurColor + ",
"vec3( 0.101, 0.355, 0.365 ) * blur1Color + ",
"vec3( 0.119, 0.208, 0.0 ) * blur2Color + ",
"vec3( 0.114, 0.0, 0.0 ) * blur3Color + ",
"vec3( 0.444, 0.0, 0.0 ) * blur4Color );",
"outgoingLight *= sqrt( colDiffuse.xyz );",
"outgoingLight += ambientLightColor * diffuse * colDiffuse.xyz + totalSpecularLight;",
"#ifndef VERSION1",
"outgoingLight = sqrt( outgoingLight );",
"#endif",
"}",
THREE.ShaderChunk[ "fog_fragment" ],
"gl_FragColor = vec4( outgoingLight, diffuseColor.a );", // TODO, this should be pre-multiplied to allow for bright highlights on very transparent objects
"}"
].join("\n"),
vertexShader: [
"attribute vec4 tangent;",
"#ifdef VERTEX_TEXTURES",
"uniform sampler2D tDisplacement;",
"uniform float uDisplacementScale;",
"uniform float uDisplacementBias;",
"#endif",
"varying vec3 vTangent;",
"varying vec3 vBinormal;",
"varying vec3 vNormal;",
"varying vec2 vUv;",
"#if MAX_POINT_LIGHTS > 0",
"uniform vec3 pointLightPosition[ MAX_POINT_LIGHTS ];",
"uniform float pointLightDistance[ MAX_POINT_LIGHTS ];",
"uniform float pointLightDecay[ MAX_POINT_LIGHTS ];",
"varying vec4 vPointLight[ MAX_POINT_LIGHTS ];",
"#endif",
"varying vec3 vViewPosition;",
THREE.ShaderChunk[ "common" ],
"void main() {",
"vec4 worldPosition = modelMatrix * vec4( position, 1.0 );",
"vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );",
"vViewPosition = -mvPosition.xyz;",
"vNormal = normalize( normalMatrix * normal );",
// tangent and binormal vectors
"vTangent = normalize( normalMatrix * tangent.xyz );",
"vBinormal = cross( vNormal, vTangent ) * tangent.w;",
"vBinormal = normalize( vBinormal );",
"vUv = uv;",
// point lights
"#if MAX_POINT_LIGHTS > 0",
"for( int i = 0; i < MAX_POINT_LIGHTS; i++ ) {",
"vec4 lPosition = viewMatrix * vec4( pointLightPosition[ i ], 1.0 );",
"vec3 lVector = lPosition.xyz - mvPosition.xyz;",
"float attenuation = calcLightAttenuation( length( lVector ), pointLightDistance[ i ], pointLightDecay[i] );",
"lVector = normalize( lVector );",
"vPointLight[ i ] = vec4( lVector, attenuation );",
"}",
"#endif",
// displacement mapping
"#ifdef VERTEX_TEXTURES",
"vec3 dv = texture2D( tDisplacement, uv ).xyz;",
"float df = uDisplacementScale * dv.x + uDisplacementBias;",
"vec4 displacedPosition = vec4( vNormal.xyz * df, 0.0 ) + mvPosition;",
"gl_Position = projectionMatrix * displacedPosition;",
"#else",
"gl_Position = projectionMatrix * mvPosition;",
"#endif",
"}"
].join("\n"),
vertexShaderUV: [
"attribute vec4 tangent;",
"#ifdef VERTEX_TEXTURES",
"uniform sampler2D tDisplacement;",
"uniform float uDisplacementScale;",
"uniform float uDisplacementBias;",
"#endif",
"varying vec3 vTangent;",
"varying vec3 vBinormal;",
"varying vec3 vNormal;",
"varying vec2 vUv;",
"#if MAX_POINT_LIGHTS > 0",
"uniform vec3 pointLightPosition[ MAX_POINT_LIGHTS ];",
"uniform float pointLightDistance[ MAX_POINT_LIGHTS ];",
"uniform float pointLightDecay[ MAX_POINT_LIGHTS ];",
"varying vec4 vPointLight[ MAX_POINT_LIGHTS ];",
"#endif",
"varying vec3 vViewPosition;",
THREE.ShaderChunk[ "common" ],
"void main() {",
"vec4 worldPosition = modelMatrix * vec4( position, 1.0 );",
"vec4 mvPosition = modelViewMatrix * vec4( position, 1.0 );",
"vViewPosition = -mvPosition.xyz;",
"vNormal = normalize( normalMatrix * normal );",
// tangent and binormal vectors
"vTangent = normalize( normalMatrix * tangent.xyz );",
"vBinormal = cross( vNormal, vTangent ) * tangent.w;",
"vBinormal = normalize( vBinormal );",
"vUv = uv;",
// point lights
"#if MAX_POINT_LIGHTS > 0",
"for( int i = 0; i < MAX_POINT_LIGHTS; i++ ) {",
"vec4 lPosition = viewMatrix * vec4( pointLightPosition[ i ], 1.0 );",
"vec3 lVector = lPosition.xyz - mvPosition.xyz;",
"float attenuation = calcLightAttenuation( length( lVector ), pointLightDistance[ i ], pointLightDecay[i] );",
"lVector = normalize( lVector );",
"vPointLight[ i ] = vec4( lVector, attenuation );",
"}",
"#endif",
"gl_Position = vec4( uv.x * 2.0 - 1.0, uv.y * 2.0 - 1.0, 0.0, 1.0 );",
"}"
].join("\n")
},
/* ------------------------------------------------------------------------------------------
// Beckmann distribution function
// - to be used in specular term of skin shader
// - render a screen-aligned quad to precompute a 512 x 512 texture
//
// - from http://developer.nvidia.com/node/171
------------------------------------------------------------------------------------------ */
"beckmann" : {
uniforms: {},
vertexShader: [
"varying vec2 vUv;",
"void main() {",
"vUv = uv;",
"gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );",
"}"
].join("\n"),
fragmentShader: [
"varying vec2 vUv;",
"float PHBeckmann( float ndoth, float m ) {",
"float alpha = acos( ndoth );",
"float ta = tan( alpha );",
"float val = 1.0 / ( m * m * pow( ndoth, 4.0 ) ) * exp( -( ta * ta ) / ( m * m ) );",
"return val;",
"}",
"float KSTextureCompute( vec2 tex ) {",
// Scale the value to fit within [0,1] invert upon lookup.
"return 0.5 * pow( PHBeckmann( tex.x, tex.y ), 0.1 );",
"}",
"void main() {",
"float x = KSTextureCompute( vUv );",
"gl_FragColor = vec4( x, x, x, 1.0 );",
"}"
].join("\n")
}
};