131 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
		
		
			
		
	
	
			131 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
|  | import { | ||
|  | 	Mesh, | ||
|  | 	ShaderMaterial, | ||
|  | 	SphereGeometry | ||
|  | } from 'three'; | ||
|  | 
 | ||
|  | class LightProbeHelper extends Mesh { | ||
|  | 
 | ||
|  | 	constructor( lightProbe, size ) { | ||
|  | 
 | ||
|  | 		const material = new ShaderMaterial( { | ||
|  | 
 | ||
|  | 			type: 'LightProbeHelperMaterial', | ||
|  | 
 | ||
|  | 			uniforms: { | ||
|  | 
 | ||
|  | 				sh: { value: lightProbe.sh.coefficients }, // by reference
 | ||
|  | 
 | ||
|  | 				intensity: { value: lightProbe.intensity } | ||
|  | 
 | ||
|  | 			}, | ||
|  | 
 | ||
|  | 			vertexShader: [ | ||
|  | 
 | ||
|  | 				'varying vec3 vNormal;', | ||
|  | 
 | ||
|  | 				'void main() {', | ||
|  | 
 | ||
|  | 				'	vNormal = normalize( normalMatrix * normal );', | ||
|  | 
 | ||
|  | 				'	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );', | ||
|  | 
 | ||
|  | 				'}', | ||
|  | 
 | ||
|  | 			].join( '\n' ), | ||
|  | 
 | ||
|  | 			fragmentShader: [ | ||
|  | 
 | ||
|  | 				'#define RECIPROCAL_PI 0.318309886', | ||
|  | 
 | ||
|  | 				'vec3 inverseTransformDirection( in vec3 normal, in mat4 matrix ) {', | ||
|  | 
 | ||
|  | 				'	// matrix is assumed to be orthogonal', | ||
|  | 
 | ||
|  | 				'	return normalize( ( vec4( normal, 0.0 ) * matrix ).xyz );', | ||
|  | 
 | ||
|  | 				'}', | ||
|  | 
 | ||
|  | 				'// source: https://graphics.stanford.edu/papers/envmap/envmap.pdf', | ||
|  | 				'vec3 shGetIrradianceAt( in vec3 normal, in vec3 shCoefficients[ 9 ] ) {', | ||
|  | 
 | ||
|  | 				'	// normal is assumed to have unit length', | ||
|  | 
 | ||
|  | 				'	float x = normal.x, y = normal.y, z = normal.z;', | ||
|  | 
 | ||
|  | 				'	// band 0', | ||
|  | 				'	vec3 result = shCoefficients[ 0 ] * 0.886227;', | ||
|  | 
 | ||
|  | 				'	// band 1', | ||
|  | 				'	result += shCoefficients[ 1 ] * 2.0 * 0.511664 * y;', | ||
|  | 				'	result += shCoefficients[ 2 ] * 2.0 * 0.511664 * z;', | ||
|  | 				'	result += shCoefficients[ 3 ] * 2.0 * 0.511664 * x;', | ||
|  | 
 | ||
|  | 				'	// band 2', | ||
|  | 				'	result += shCoefficients[ 4 ] * 2.0 * 0.429043 * x * y;', | ||
|  | 				'	result += shCoefficients[ 5 ] * 2.0 * 0.429043 * y * z;', | ||
|  | 				'	result += shCoefficients[ 6 ] * ( 0.743125 * z * z - 0.247708 );', | ||
|  | 				'	result += shCoefficients[ 7 ] * 2.0 * 0.429043 * x * z;', | ||
|  | 				'	result += shCoefficients[ 8 ] * 0.429043 * ( x * x - y * y );', | ||
|  | 
 | ||
|  | 				'	return result;', | ||
|  | 
 | ||
|  | 				'}', | ||
|  | 
 | ||
|  | 				'uniform vec3 sh[ 9 ]; // sh coefficients', | ||
|  | 
 | ||
|  | 				'uniform float intensity; // light probe intensity', | ||
|  | 
 | ||
|  | 				'varying vec3 vNormal;', | ||
|  | 
 | ||
|  | 				'void main() {', | ||
|  | 
 | ||
|  | 				'	vec3 normal = normalize( vNormal );', | ||
|  | 
 | ||
|  | 				'	vec3 worldNormal = inverseTransformDirection( normal, viewMatrix );', | ||
|  | 
 | ||
|  | 				'	vec3 irradiance = shGetIrradianceAt( worldNormal, sh );', | ||
|  | 
 | ||
|  | 				'	vec3 outgoingLight = RECIPROCAL_PI * irradiance * intensity;', | ||
|  | 
 | ||
|  | 				'	gl_FragColor = linearToOutputTexel( vec4( outgoingLight, 1.0 ) );', | ||
|  | 
 | ||
|  | 				'}' | ||
|  | 
 | ||
|  | 			].join( '\n' ) | ||
|  | 
 | ||
|  | 		} ); | ||
|  | 
 | ||
|  | 		const geometry = new SphereGeometry( 1, 32, 16 ); | ||
|  | 
 | ||
|  | 		super( geometry, material ); | ||
|  | 
 | ||
|  | 		this.lightProbe = lightProbe; | ||
|  | 		this.size = size; | ||
|  | 		this.type = 'LightProbeHelper'; | ||
|  | 
 | ||
|  | 		this.onBeforeRender(); | ||
|  | 
 | ||
|  | 	} | ||
|  | 
 | ||
|  | 	dispose() { | ||
|  | 
 | ||
|  | 		this.geometry.dispose(); | ||
|  | 		this.material.dispose(); | ||
|  | 
 | ||
|  | 	} | ||
|  | 
 | ||
|  | 	onBeforeRender() { | ||
|  | 
 | ||
|  | 		this.position.copy( this.lightProbe.position ); | ||
|  | 
 | ||
|  | 		this.scale.set( 1, 1, 1 ).multiplyScalar( this.size ); | ||
|  | 
 | ||
|  | 		this.material.uniforms.intensity.value = this.lightProbe.intensity; | ||
|  | 
 | ||
|  | 	} | ||
|  | 
 | ||
|  | } | ||
|  | 
 | ||
|  | export { LightProbeHelper }; |