Move light count into struct

Author: gkjohnson

README.md

@@ -116,7 +116,6 @@ ptMaterial.materials.updateFrom( materials, textures );
 
 // update the lights
 ptMaterial.lights.updateFrom( lights );
-ptMaterial.lightCount = lights.length;
 
 // set the environment map
 const texture = await new RGBELoader().loadAsync( envMapUrl );
@@ -524,8 +523,7 @@ _extends MaterialBase_
 	textures: RenderTarget2DArray,
 
 	// Light information
-	lights: LightsTexture,
-	lightCount = 0: Number,
+	lights: LightsInfoUniformStruct,
 	iesProfiles: IESProfilesTexture,
 
 	// Environment Map information
@@ -649,11 +647,9 @@ Updates the size and values of the texture to align with the provided set of mat
 
 The "matte" and "side" values must be updated explicitly.
 
-## LightsTexture
+## LightsInfoUniformStruct
 
-_extends DataTexture_
-
-Helper texture uniform for encoding lights as texture data.
+Helper uniform for encoding lights as texture data with count.
 
 ### .updateFrom
 

example/spotLights.js

@@ -261,7 +261,6 @@ async function init() {
 			material.materials.updateFrom( materials, textures );
 			material.iesProfiles.updateFrom( renderer, iesTextures );
 			material.lights.updateFrom( lights );
-			material.lightCount = lights.length;
 			ptRenderer.material.envMapInfo.updateFrom( scene.environment );
 
 			generator.dispose();

src/index.js

@@ -15,7 +15,7 @@ export * from './uniforms/MaterialsTexture.js';
 export * from './uniforms/RenderTarget2DArray.js';
 export * from './uniforms/EquirectHdrInfoUniform.js';
 export * from './uniforms/PhysicalCameraUniform.js';
-export * from './uniforms/LightsTexture.js';
+export * from './uniforms/LightsInfoUniformStruct.js';
 export * from './uniforms/IESProfilesTexture.js';
 
 // utils

src/materials/PhysicalPathTracingMaterial.js

@@ -13,7 +13,7 @@ import { shaderLightSampling } from '../shader/shaderLightSampling.js';
 import { shaderUtils } from '../shader/shaderUtils.js';
 import { PhysicalCameraUniform } from '../uniforms/PhysicalCameraUniform.js';
 import { EquirectHdrInfoUniform } from '../uniforms/EquirectHdrInfoUniform.js';
-import { LightsTexture } from '../uniforms/LightsTexture.js';
+import { LightsInfoUniformStruct } from '../uniforms/LightsInfoUniformStruct.js';
 import { IESProfilesTexture } from '../uniforms/IESProfilesTexture.js';
 
 export class PhysicalPathTracingMaterial extends MaterialBase {
@@ -55,8 +55,7 @@ export class PhysicalPathTracingMaterial extends MaterialBase {
 				materialIndexAttribute: { value: new UIntVertexAttributeTexture() },
 				materials: { value: new MaterialsTexture() },
 				textures: { value: new RenderTarget2DArray().texture },
-				lights: { value: new LightsTexture() },
-				lightCount: { value: 0 },
+				lights: { value: new LightsInfoUniformStruct() },
 				iesProfiles: { value: new IESProfilesTexture().texture },
 				cameraWorldMatrix: { value: new Matrix4() },
 				invProjectionMatrix: { value: new Matrix4() },
@@ -138,8 +137,7 @@ export class PhysicalPathTracingMaterial extends MaterialBase {
 				uniform int seed;
 				uniform float opacity;
 				uniform sampler2D materials;
-				uniform sampler2D lights;
-				uniform uint lightCount;
+				uniform LightsInfo lights;
 				uniform sampler2DArray iesProfiles;
 
 				${ shaderLightSampling }
@@ -420,7 +418,7 @@ export class PhysicalPathTracingMaterial extends MaterialBase {
 
 						bool hit = bvhIntersectFirstHit( bvh, rayOrigin, rayDirection, faceIndices, faceNormal, barycoord, side, dist );
 
-						LightSampleRec lightHit = lightsClosestHit( lights, lightCount, rayOrigin, rayDirection );
+						LightSampleRec lightHit = lightsClosestHit( lights.tex, lights.count, rayOrigin, rayDirection );
 
 						if ( lightHit.hit && ( lightHit.dist < dist || !hit ) ) {
 
@@ -433,7 +431,7 @@ export class PhysicalPathTracingMaterial extends MaterialBase {
 								#if FEATURE_MIS
 
 								// weight the contribution
-								float misWeight = misHeuristic( sampleRec.pdf, lightHit.pdf / float( lightCount + 1u ) );
+								float misWeight = misHeuristic( sampleRec.pdf, lightHit.pdf / float( lights.count + 1u ) );
 								gl_FragColor.rgb += lightHit.emission * throughputColor * misWeight;
 
 								#else
@@ -463,7 +461,7 @@ export class PhysicalPathTracingMaterial extends MaterialBase {
 								// get the PDF of the hit envmap point
 								vec3 envColor;
 								float envPdf = envMapSample( environmentRotation * rayDirection, envMapInfo, envColor );
-								envPdf /= float( lightCount + 1u );
+								envPdf /= float( lights.count + 1u );
 
 								// and weight the contribution
 								float misWeight = misHeuristic( sampleRec.pdf, envPdf );
@@ -788,10 +786,10 @@ export class PhysicalPathTracingMaterial extends MaterialBase {
 						#if FEATURE_MIS
 
 						// uniformly pick a light or environment map
-						if( rand() > 1.0 / float( lightCount + 1u ) ) {
+						if( rand() > 1.0 / float( lights.count + 1u ) ) {
 
 							// sample a light or environment
-							LightSampleRec lightSampleRec = randomLightSample( lights, iesProfiles, lightCount, rayOrigin );
+							LightSampleRec lightSampleRec = randomLightSample( lights.tex, iesProfiles, lights.count, rayOrigin );
 
 							bool isSampleBelowSurface = dot( faceNormal, lightSampleRec.direction ) < 0.0;
 							if ( isSampleBelowSurface ) {
@@ -814,7 +812,7 @@ export class PhysicalPathTracingMaterial extends MaterialBase {
 								if ( lightMaterialPdf > 0.0 && isValidSampleColor ) {
 
 									// weight the direct light contribution
-									float lightPdf = lightSampleRec.pdf / float( lightCount + 1u );
+									float lightPdf = lightSampleRec.pdf / float( lights.count + 1u );
 									float misWeight = misHeuristic( lightPdf, lightMaterialPdf );
 									gl_FragColor.rgb += lightSampleRec.emission * throughputColor * sampleColor * misWeight / lightPdf;
 
@@ -854,7 +852,7 @@ export class PhysicalPathTracingMaterial extends MaterialBase {
 								if ( envMaterialPdf > 0.0 && isValidSampleColor ) {
 
 									// weight the direct light contribution
-									envPdf /= float( lightCount + 1u );
+									envPdf /= float( lights.count + 1u );
 									float misWeight = misHeuristic( envPdf, envMaterialPdf );
 									gl_FragColor.rgb += attenuatedColor * environmentIntensity * envColor * throughputColor * sampleColor * misWeight / envPdf;
 

src/shader/shaderStructs.js

@@ -212,6 +212,14 @@ export const shaderLightStruct = /* glsl */ `
 	#define RECT_AREA_LIGHT_TYPE 0
 	#define CIRC_AREA_LIGHT_TYPE 1
 	#define SPOT_LIGHT_TYPE 2
+
+	struct LightsInfo {
+
+		sampler2D tex;
+		uint count;
+
+	};
+
 	struct Light {
 
 		vec3 position;

src/uniforms/LightsTexture.js renamed to src/uniforms/LightsInfoUniformStruct.js

@@ -4,36 +4,39 @@ const LIGHT_PIXELS = 6;
 const RECT_AREA_LIGHT = 0;
 const CIRC_AREA_LIGHT = 1;
 const SPOT_LIGHT = 2;
-export class LightsTexture extends DataTexture {
+export class LightsInfoUniformStruct {
 
 	constructor() {
 
-		super( new Float32Array( 4 ), 1, 1 );
+		const tex = new DataTexture( new Float32Array( 4 ), 1, 1 );
+		tex.format = RGBAFormat;
+		tex.type = FloatType;
+		tex.wrapS = ClampToEdgeWrapping;
+		tex.wrapT = ClampToEdgeWrapping;
+		tex.generateMipmaps = false;
 
-		this.format = RGBAFormat;
-		this.type = FloatType;
-		this.wrapS = ClampToEdgeWrapping;
-		this.wrapT = ClampToEdgeWrapping;
-		this.generateMipmaps = false;
+		this.tex = tex;
+		this.count = 0;
 
 	}
 
 	updateFrom( lights, iesTextures = [] ) {
 
-		const pixelCount = lights.length * LIGHT_PIXELS;
+		const tex = this.tex;
+		const pixelCount = Math.max( lights.length * LIGHT_PIXELS, 1 );
 		const dimension = Math.ceil( Math.sqrt( pixelCount ) );
 
-		if ( this.image.width !== dimension ) {
+		if ( tex.image.width !== dimension ) {
 
-			this.dispose();
+			tex.dispose();
 
-			this.image.data = new Float32Array( dimension * dimension * 4 );
-			this.image.width = dimension;
-			this.image.height = dimension;
+			tex.image.data = new Float32Array( dimension * dimension * 4 );
+			tex.image.width = dimension;
+			tex.image.height = dimension;
 
 		}
 
-		const floatArray = this.image.data;
+		const floatArray = tex.image.data;
 
 		const u = new Vector3();
 		const v = new Vector3();
@@ -151,9 +154,8 @@ export class LightsTexture extends DataTexture {
 
 		}
 
-		window.LIGHT_ARRAY = floatArray;
-
-		this.needsUpdate = true;
+		tex.needsUpdate = true;
+		this.count = lights.length;
 
 	}