feat: pbr diffuse lighting in srgb. (doodlum#429)

* feat: PBR diffuse calculated in sRGB. * style: 🎨 apply clang-format changes * feat: slider for base color gamma. * feat: transform for other PBR diffuse colors. * style: 🎨 apply clang-format changes * fix: fix for pbr-non-pbr land blending. * fix: default base color gamma set to 1.9. --------- Co-authored-by: Ilya Perapechka <[email protected]> Co-authored-by: Jonahex <[email protected]>
FlayaN · Aug 18, 2024 · 70b8a12 · 70b8a12
1 parent c644210
commit 70b8a12
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Showing 7 changed files with 93 additions and 71 deletions.
diff --git a/package/Shaders/AmbientCompositeCS.hlsl b/package/Shaders/AmbientCompositeCS.hlsl
@@ -55,8 +55,6 @@ RWTexture2D<half3> DiffuseAmbientRW : register(u1);
 	half3 linDirectionalAmbientColor = sRGB2Lin(directionalAmbientColor);
 	half3 linDiffuseColor = sRGB2Lin(diffuseColor);
 
-	half3 linAmbient = lerp(sRGB2Lin(albedo * directionalAmbientColor), linAlbedo * linDirectionalAmbientColor, pbrWeight);
-
 	half visibility = 1.0;
 #if defined(SKYLIGHTING)
 	float rawDepth = DepthTexture[dispatchID.xy];
@@ -89,11 +87,10 @@ RWTexture2D<half3> DiffuseAmbientRW : register(u1);
 	linDiffuseColor += ssgiDiffuse.rgb;
 #endif
 
-	linAmbient *= visibility;
 	diffuseColor = Lin2sRGB(linDiffuseColor);
 	directionalAmbientColor = Lin2sRGB(linDirectionalAmbientColor * visibility);
 
-	diffuseColor = lerp(diffuseColor + directionalAmbientColor * albedo, Lin2sRGB(linDiffuseColor + linAmbient), pbrWeight);
+	diffuseColor = diffuseColor + directionalAmbientColor * albedo;
 
 	MainRW[dispatchID.xy] = diffuseColor;
 };
diff --git a/package/Shaders/Common/PBR.hlsli b/package/Shaders/Common/PBR.hlsli
@@ -85,6 +85,32 @@ namespace PBR
 		return surfaceProperties;
 	}
 
+	struct LightProperties
+	{
+		float3 LightColor;
+		float3 CoatLightColor;
+		float3 LinearLightColor;
+		float3 LinearCoatLightColor;
+	};
+
+	LightProperties InitLightProperties(float3 lightColor, float3 nonParallaxShadow, float3 parallaxShadow)
+	{
+		LightProperties result;
+		result.LightColor = lightColor * nonParallaxShadow * parallaxShadow;
+		result.LinearLightColor = sRGB2Lin(lightColor) * nonParallaxShadow * parallaxShadow;
+		[branch] if ((PBRFlags & TruePBR_InterlayerParallax) != 0)
+		{
+			result.CoatLightColor = lightColor * nonParallaxShadow;
+			result.LinearCoatLightColor = sRGB2Lin(lightColor) * nonParallaxShadow;
+		}
+		else
+		{
+			result.CoatLightColor = result.LightColor;
+			result.LinearCoatLightColor = result.LinearLightColor;
+		}
+		return result;
+	}
+
 	float3 AdjustDirectionalLightColor(float3 lightColor)
 	{
 		return pbrSettings.DirectionalLightColorMultiplier * sRGB2Lin(lightColor);
@@ -372,7 +398,7 @@ namespace PBR
 		return color;
 	}
 
-	void GetDirectLightInput(out float3 diffuse, out float3 coatDiffuse, out float3 transmission, out float3 specular, float3 N, float3 coatN, float3 V, float3 coatV, float3 L, float3 coatL, float3 lightColor, float3 coatLightColor, SurfaceProperties surfaceProperties,
+	void GetDirectLightInput(out float3 diffuse, out float3 coatDiffuse, out float3 transmission, out float3 specular, float3 N, float3 coatN, float3 V, float3 coatV, float3 L, float3 coatL, LightProperties lightProperties, SurfaceProperties surfaceProperties,
 		float3x3 tbnTr, float2 uv)
 	{
 		diffuse = 0;
@@ -397,12 +423,12 @@ namespace PBR
 #if !defined(LANDSCAPE) && !defined(LODLANDSCAPE)
 		[branch] if ((PBRFlags & TruePBR_HairMarschner) != 0)
 		{
-			transmission += PI * lightColor * GetHairColorMarschner(N, V, L, NdotL, NdotV, VdotL, 0, 1, 0, surfaceProperties);
+			transmission += PI * lightProperties.LightColor * GetHairColorMarschner(N, V, L, NdotL, NdotV, VdotL, 0, 1, 0, surfaceProperties);
 		}
 		else
 #endif
 		{
-			diffuse += lightColor * satNdotL;
+			diffuse += lightProperties.LightColor * satNdotL;
 
 #if defined(GLINT)
 			GlintInput glintInput;
@@ -418,9 +444,9 @@ namespace PBR
 
 			float3 F;
 #if defined(GLINT)
-			specular += PI * GetSpecularDirectLightMultiplierMicrofacetWithGlint(surfaceProperties.Roughness, surfaceProperties.F0, satNdotL, satNdotV, satNdotH, satVdotH, glintInput, F) * lightColor * satNdotL;
+			specular += PI * GetSpecularDirectLightMultiplierMicrofacetWithGlint(surfaceProperties.Roughness, surfaceProperties.F0, satNdotL, satNdotV, satNdotH, satVdotH, glintInput, F) * lightProperties.LinearLightColor * satNdotL;
 #else
-			specular += PI * GetSpecularDirectLightMultiplierMicrofacet(surfaceProperties.Roughness, surfaceProperties.F0, satNdotL, satNdotV, satNdotH, satVdotH, F) * lightColor * satNdotL;
+			specular += PI * GetSpecularDirectLightMultiplierMicrofacet(surfaceProperties.Roughness, surfaceProperties.F0, satNdotL, satNdotV, satNdotH, satVdotH, F) * lightProperties.LinearLightColor * satNdotL;
 #endif
 
 			float2 specularBRDF = 0;
@@ -433,7 +459,7 @@ namespace PBR
 #if !defined(LANDSCAPE) && !defined(LODLANDSCAPE)
 			[branch] if ((PBRFlags & TruePBR_Fuzz) != 0)
 			{
-				float3 fuzzSpecular = PI * GetSpecularDirectLightMultiplierMicroflakes(surfaceProperties.Roughness, surfaceProperties.FuzzColor, satNdotL, satNdotV, satNdotH, satVdotH) * lightColor * satNdotL;
+				float3 fuzzSpecular = PI * GetSpecularDirectLightMultiplierMicroflakes(surfaceProperties.Roughness, surfaceProperties.FuzzColor, satNdotL, satNdotV, satNdotH, satVdotH) * lightProperties.LinearLightColor * satNdotL;
 				[branch] if (pbrSettings.UseMultipleScattering)
 				{
 					fuzzSpecular *= 1 + surfaceProperties.FuzzColor * (1 / (specularBRDF.x + specularBRDF.y) - 1);
@@ -448,7 +474,7 @@ namespace PBR
 				float forwardScatter = exp2(saturate(-VdotL) * subsurfacePower - subsurfacePower);
 				float backScatter = saturate(satNdotL * surfaceProperties.Thickness + (1.0 - surfaceProperties.Thickness)) * 0.5;
 				float subsurface = lerp(backScatter, 1, forwardScatter) * (1.0 - surfaceProperties.Thickness);
-				transmission += surfaceProperties.SubsurfaceColor * subsurface * lightColor;
+				transmission += surfaceProperties.SubsurfaceColor * subsurface * lightProperties.LightColor;
 			}
 			else if ((PBRFlags & TruePBR_TwoLayer) != 0)
 			{
@@ -467,13 +493,13 @@ namespace PBR
 				}
 
 				float3 coatF;
-				float3 coatSpecular = PI * GetSpecularDirectLightMultiplierMicrofacet(surfaceProperties.CoatRoughness, surfaceProperties.CoatF0, coatNdotL, coatNdotV, coatNdotH, coatVdotH, coatF) * coatLightColor * coatNdotL;
+				float3 coatSpecular = PI * GetSpecularDirectLightMultiplierMicrofacet(surfaceProperties.CoatRoughness, surfaceProperties.CoatF0, coatNdotL, coatNdotV, coatNdotH, coatVdotH, coatF) * lightProperties.LinearCoatLightColor * coatNdotL;
 
 				float3 layerAttenuation = 1 - coatF * surfaceProperties.CoatStrength;
 				diffuse *= layerAttenuation;
 				specular *= layerAttenuation;
 
-				coatDiffuse += coatLightColor * coatNdotL;
+				coatDiffuse += lightProperties.CoatLightColor * coatNdotL;
 				specular += coatSpecular * surfaceProperties.CoatStrength;
 			}
 #endif

diff --git a/package/Shaders/Common/SharedData.hlsli b/package/Shaders/Common/SharedData.hlsli
@@ -137,6 +137,7 @@ struct PBRSettings
 	float DirectionalLightColorMultiplier;
 	float PointLightColorMultiplier;
 	float AmbientLightColorMultiplier;
+	float BaseColorGamma;
 	uint UseMultipleScattering;
 	uint UseMultiBounceAO;
 	uint3 pad0;