/**
* @author daoshengmu / http://dsmu.me/
*
* ------------------------------------------------------------------------------------------
* Subsurface Scattering shader
* Base on GDC 2011 – Approximating Translucency for a Fast, Cheap and Convincing Subsurface Scattering Look
* https://colinbarrebrisebois.com/2011/03/07/gdc-2011-approximating-translucency-for-a-fast-cheap-and-convincing-subsurface-scattering-look/
*------------------------------------------------------------------------------------------
*/
THREE.TranslucentShader = {
uniforms: THREE.UniformsUtils.merge( [
THREE.UniformsLib[ "common" ],
THREE.UniformsLib[ "lights" ],
{
"color": { value: new THREE.Color( 0xffffff ) },
"diffuse": { value: new THREE.Color( 0xffffff ) },
"specular": { value: new THREE.Color( 0xffffff ) },
"emissive": { value: new THREE.Color( 0x000000 ) },
"opacity": { value: 1 },
"shininess": { value: 1 },
"thicknessMap": { value: null },
"thicknessColor": { value: new THREE.Color( 0xffffff ) },
"thicknessDistortion": { value: 0.1 },
"thicknessAmbient": { value: 0.0 },
"thicknessAttenuation": { value: 0.1 },
"thicknessPower": { value: 2.0 },
"thicknessScale": { value: 10.0 }
}
] ),
vertexShader: [
"varying vec3 vNormal;",
"varying vec2 vUv;",
"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 );",
" vUv = uv;",
" gl_Position = projectionMatrix * mvPosition;",
"}",
].join( "\n" ),
fragmentShader: [
"#define USE_UV",
"#define USE_MAP",
"#define PHONG",
"#define TRANSLUCENT",
"#include <common>",
"#include <bsdfs>",
"#include <uv_pars_fragment>",
"#include <map_pars_fragment>",
"#include <lights_phong_pars_fragment>",
"varying vec3 vColor;",
"uniform vec3 diffuse;",
"uniform vec3 specular;",
"uniform vec3 emissive;",
"uniform float opacity;",
"uniform float shininess;",
// Translucency
"uniform sampler2D thicknessMap;",
"uniform float thicknessPower;",
"uniform float thicknessScale;",
"uniform float thicknessDistortion;",
"uniform float thicknessAmbient;",
"uniform float thicknessAttenuation;",
"uniform vec3 thicknessColor;",
THREE.ShaderChunk[ "lights_pars_begin" ],
"void RE_Direct_Scattering(const in IncidentLight directLight, const in vec2 uv, const in GeometricContext geometry, inout ReflectedLight reflectedLight) {",
" vec3 thickness = thicknessColor * texture2D(thicknessMap, uv).r;",
" vec3 scatteringHalf = normalize(directLight.direction + (geometry.normal * thicknessDistortion));",
" float scatteringDot = pow(saturate(dot(geometry.viewDir, -scatteringHalf)), thicknessPower) * thicknessScale;",
" vec3 scatteringIllu = (scatteringDot + thicknessAmbient) * thickness;",
" reflectedLight.directDiffuse += scatteringIllu * thicknessAttenuation * directLight.color;",
"}",
"void main() {",
" vec3 normal = normalize( vNormal );",
" vec3 viewerDirection = normalize( vViewPosition );",
" vec4 diffuseColor = vec4( diffuse, opacity );",
" ReflectedLight reflectedLight = ReflectedLight( vec3( 0.0 ), vec3( 0.0 ), vec3( 0.0 ), vec3( 0.0 ) );",
THREE.ShaderChunk[ "map_fragment" ],
THREE.ShaderChunk[ "color_fragment" ],
THREE.ShaderChunk[ "specularmap_fragment" ],
" vec3 totalEmissiveRadiance = emissive;",
THREE.ShaderChunk[ "lights_phong_fragment" ],
// Doing lights fragment begin.
" GeometricContext geometry;",
" geometry.position = - vViewPosition;",
" geometry.normal = normal;",
" geometry.viewDir = normalize( vViewPosition );",
" IncidentLight directLight;",
" #if ( NUM_POINT_LIGHTS > 0 ) && defined( RE_Direct )",
" PointLight pointLight;",
" #pragma unroll_loop",
" for ( int i = 0; i < NUM_POINT_LIGHTS; i ++ ) {",
" pointLight = pointLights[ i ];",
" getPointDirectLightIrradiance( pointLight, geometry, directLight );",
" #ifdef USE_SHADOWMAP",
" directLight.color *= all( bvec2( pointLight.shadow, directLight.visible ) ) ? getPointShadow( pointShadowMap[ i ], pointLight.shadowMapSize, pointLight.shadowBias, pointLight.shadowRadius, vPointShadowCoord[ i ], pointLight.shadowCameraNear, pointLight.shadowCameraFar ) : 1.0;",
" #endif",
" RE_Direct( directLight, geometry, material, reflectedLight );",
" #if defined( TRANSLUCENT ) && defined( USE_UV )",
" RE_Direct_Scattering(directLight, vUv, geometry, reflectedLight);",
" #endif",
" }",
" #endif",
" #if ( NUM_DIR_LIGHTS > 0 ) && defined( RE_Direct )",
" DirectionalLight directionalLight;",
" #pragma unroll_loop",
" for ( int i = 0; i < NUM_DIR_LIGHTS; i ++ ) {",
" directionalLight = directionalLights[ i ];",
" getDirectionalDirectLightIrradiance( directionalLight, geometry, directLight );",
" #ifdef USE_SHADOWMAP",
" directLight.color *= all( bvec2( directionalLight.shadow, directLight.visible ) ) ? getShadow( directionalShadowMap[ i ], directionalLight.shadowMapSize, directionalLight.shadowBias, directionalLight.shadowRadius, vDirectionalShadowCoord[ i ] ) : 1.0;",
" #endif",
" RE_Direct( directLight, geometry, material, reflectedLight );",
" #if defined( TRANSLUCENT ) && defined( USE_UV )",
" RE_Direct_Scattering(directLight, vUv, geometry, reflectedLight);",
" #endif",
" }",
" #endif",
" #if defined( RE_IndirectDiffuse )",
" vec3 irradiance = getAmbientLightIrradiance( ambientLightColor );",
" #if ( NUM_HEMI_LIGHTS > 0 )",
" #pragma unroll_loop",
" for ( int i = 0; i < NUM_HEMI_LIGHTS; i ++ ) {",
" irradiance += getHemisphereLightIrradiance( hemisphereLights[ i ], geometry );",
" }",
" #endif",
" #endif",
" #if defined( RE_IndirectSpecular )",
" vec3 radiance = vec3( 0.0 );",
" vec3 clearcoatRadiance = vec3( 0.0 );",
" #endif",
THREE.ShaderChunk[ "lights_fragment_end" ],
" vec3 outgoingLight = reflectedLight.directDiffuse + reflectedLight.indirectDiffuse + reflectedLight.directSpecular + reflectedLight.indirectSpecular + totalEmissiveRadiance;",
" gl_FragColor = vec4( outgoingLight, diffuseColor.a );", // TODO, this should be pre-multiplied to allow for bright highlights on very transparent objects
THREE.ShaderChunk[ "encodings_fragment" ],
"}"
].join( "\n" ),
};
