91 lines
3.2 KiB
JavaScript
91 lines
3.2 KiB
JavaScript
|
import {
|
|||
|
Color,
|
|||
|
ShaderChunk,
|
|||
|
ShaderLib,
|
|||
|
UniformsUtils
|
|||
|
} from 'three';
|
|||
|
|
|||
|
/**
|
|||
|
* ------------------------------------------------------------------------------------------
|
|||
|
* Subsurface Scattering shader
|
|||
|
* Based 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/
|
|||
|
*------------------------------------------------------------------------------------------
|
|||
|
*/
|
|||
|
|
|||
|
function replaceAll( string, find, replace ) {
|
|||
|
|
|||
|
return string.split( find ).join( replace );
|
|||
|
|
|||
|
}
|
|||
|
|
|||
|
const meshphong_frag_head = ShaderChunk[ 'meshphong_frag' ].slice( 0, ShaderChunk[ 'meshphong_frag' ].indexOf( 'void main() {' ) );
|
|||
|
const meshphong_frag_body = ShaderChunk[ 'meshphong_frag' ].slice( ShaderChunk[ 'meshphong_frag' ].indexOf( 'void main() {' ) );
|
|||
|
|
|||
|
const SubsurfaceScatteringShader = {
|
|||
|
|
|||
|
name: 'SubsurfaceScatteringShader',
|
|||
|
|
|||
|
uniforms: UniformsUtils.merge( [
|
|||
|
ShaderLib[ 'phong' ].uniforms,
|
|||
|
{
|
|||
|
'thicknessMap': { value: null },
|
|||
|
'thicknessColor': { value: new Color( 0xffffff ) },
|
|||
|
'thicknessDistortion': { value: 0.1 },
|
|||
|
'thicknessAmbient': { value: 0.0 },
|
|||
|
'thicknessAttenuation': { value: 0.1 },
|
|||
|
'thicknessPower': { value: 2.0 },
|
|||
|
'thicknessScale': { value: 10.0 }
|
|||
|
}
|
|||
|
|
|||
|
] ),
|
|||
|
|
|||
|
vertexShader: [
|
|||
|
'#define USE_UV',
|
|||
|
ShaderChunk[ 'meshphong_vert' ],
|
|||
|
].join( '\n' ),
|
|||
|
|
|||
|
fragmentShader: [
|
|||
|
'#define USE_UV',
|
|||
|
'#define SUBSURFACE',
|
|||
|
|
|||
|
meshphong_frag_head,
|
|||
|
|
|||
|
'uniform sampler2D thicknessMap;',
|
|||
|
'uniform float thicknessPower;',
|
|||
|
'uniform float thicknessScale;',
|
|||
|
'uniform float thicknessDistortion;',
|
|||
|
'uniform float thicknessAmbient;',
|
|||
|
'uniform float thicknessAttenuation;',
|
|||
|
'uniform vec3 thicknessColor;',
|
|||
|
|
|||
|
'void RE_Direct_Scattering(const in IncidentLight directLight, const in vec2 uv, const in vec3 geometryPosition, const in vec3 geometryNormal, const in vec3 geometryViewDir, const in vec3 geometryClearcoatNormal, inout ReflectedLight reflectedLight) {',
|
|||
|
' vec3 thickness = thicknessColor * texture2D(thicknessMap, uv).r;',
|
|||
|
' vec3 scatteringHalf = normalize(directLight.direction + (geometryNormal * thicknessDistortion));',
|
|||
|
' float scatteringDot = pow(saturate(dot(geometryViewDir, -scatteringHalf)), thicknessPower) * thicknessScale;',
|
|||
|
' vec3 scatteringIllu = (scatteringDot + thicknessAmbient) * thickness;',
|
|||
|
' reflectedLight.directDiffuse += scatteringIllu * thicknessAttenuation * directLight.color;',
|
|||
|
'}',
|
|||
|
|
|||
|
meshphong_frag_body.replace( '#include <lights_fragment_begin>',
|
|||
|
|
|||
|
replaceAll(
|
|||
|
ShaderChunk[ 'lights_fragment_begin' ],
|
|||
|
'RE_Direct( directLight, geometryPosition, geometryNormal, geometryViewDir, geometryClearcoatNormal, material, reflectedLight );',
|
|||
|
[
|
|||
|
'RE_Direct( directLight, geometryPosition, geometryNormal, geometryViewDir, geometryClearcoatNormal, material, reflectedLight );',
|
|||
|
|
|||
|
'#if defined( SUBSURFACE ) && defined( USE_UV )',
|
|||
|
' RE_Direct_Scattering(directLight, vUv, geometryPosition, geometryNormal, geometryViewDir, geometryClearcoatNormal, reflectedLight);',
|
|||
|
'#endif',
|
|||
|
].join( '\n' )
|
|||
|
),
|
|||
|
|
|||
|
),
|
|||
|
|
|||
|
].join( '\n' ),
|
|||
|
|
|||
|
};
|
|||
|
|
|||
|
export { SubsurfaceScatteringShader };
|