fix: remove all linear/srgb conversion, save for pbr albedo (#420)

features/Dynamic Cubemaps/Shaders/DynamicCubemaps/DynamicCubemaps.hlsli

@@ -25,7 +25,6 @@ float3 GetDynamicCubemapSpecularIrradiance(float2 uv, float3 N, float3 VN, float
 
 	float3 specularIrradiance = specularTexture.SampleLevel(SampColorSampler, R, level).xyz;
 	specularIrradiance *= horizon;
-	specularIrradiance = sRGB2Lin(specularIrradiance);
 
 	return specularIrradiance;
 }
@@ -53,7 +52,6 @@ float3 GetDynamicCubemap(float2 uv, float3 N, float3 VN, float3 V, float roughne
 	return horizon * ((F0 + S) * specularBRDF.x + specularBRDF.y);
 #	else
 	float3 specularIrradiance = specularTexture.SampleLevel(SampColorSampler, R, level).xyz;
-	specularIrradiance = sRGB2Lin(specularIrradiance);
 
 	return specularIrradiance * ((F0 + S) * specularBRDF.x + specularBRDF.y);
 #	endif

features/Dynamic Cubemaps/Shaders/DynamicCubemaps/InferCubemapCS.hlsl

@@ -90,11 +90,10 @@ float3 GetSamplingVector(uint3 ThreadID, in RWTexture2DArray<float4> OutputTextu
 	}
 
 #if defined(REFLECTIONS)
-	color.rgb = lerp(color.rgb, sRGB2Lin(ReflectionsTexture.SampleLevel(LinearSampler, uv, 0)), saturate(mipLevel / 8.0));
+	color.rgb = lerp(color.rgb, ReflectionsTexture.SampleLevel(LinearSampler, uv, 0), saturate(mipLevel / 8.0));
 #else
-	color.rgb = lerp(color.rgb, color.rgb * sRGB2Lin(DefaultCubemap.SampleLevel(LinearSampler, uv, 0).x) * 2, saturate(mipLevel / 8.0));
+	color.rgb = lerp(color.rgb, color.rgb * DefaultCubemap.SampleLevel(LinearSampler, uv, 0).x * 2, saturate(mipLevel / 8.0));
 #endif
 
-	color.rgb = Lin2sRGB(color.rgb);
 	EnvInferredTexture[ThreadID] = max(0, color);
 }

features/Dynamic Cubemaps/Shaders/DynamicCubemaps/SpecularIrradianceCS.hlsl

@@ -118,16 +118,6 @@ float3 tangentToWorld(const float3 v, const float3 N, const float3 S, const floa
 	return S * v.x + T * v.y + N * v.z;
 }
 
-float3 sRGB2Lin(float3 color)
-{
-	return color > 0.04045 ? pow(color / 1.055 + 0.055 / 1.055, 2.4) : color / 12.92;
-}
-
-float3 Lin2sRGB(float3 color)
-{
-	return color > 0.0031308 ? 1.055 * pow(color, 1.0 / 2.4) - 0.055 : 12.92 * color;
-}
-
 [numthreads(8, 8, 1)] void main(uint3 ThreadID
 								: SV_DispatchThreadID) {
 	// Make sure we won't write past output when computing higher mipmap levels.
@@ -181,11 +171,11 @@ float3 Lin2sRGB(float3 color)
 			// Mip level to sample from.
 			float mipLevel = max(0.5 * log2(ws / wt) + 1.0, 0.0);
 
-			color += sRGB2Lin(inputTexture.SampleLevel(linear_wrap_sampler, Li, mipLevel).rgb) * cosLi;
+			color += inputTexture.SampleLevel(linear_wrap_sampler, Li, mipLevel).rgb * cosLi;
 			weight += cosLi;
 		}
 	}
 	color /= weight;
 
-	outputTexture[ThreadID] = float4(Lin2sRGB(color), 1.0);
+	outputTexture[ThreadID] = float4(color, 1.0);
 }

features/Dynamic Cubemaps/Shaders/DynamicCubemaps/UpdateCubemapCS.hlsl

@@ -59,11 +59,6 @@ cbuffer UpdateData : register(b1)
 bool IsSaturated(float value) { return value == saturate(value); }
 bool IsSaturated(float2 value) { return IsSaturated(value.x) && IsSaturated(value.y); }
 
-float3 sRGB2Lin(float3 color)
-{
-	return color > 0.04045 ? pow(color / 1.055 + 0.055 / 1.055, 2.4) : color / 12.92;
-}
-
 // Inverse project UV + raw depth into world space.
 float3 InverseProjectUVZ(float2 uv, float z)
 {
@@ -172,7 +167,7 @@ float smoothbumpstep(float edge0, float edge1, float x)
 
 		if (linearDepth > 16.5) {  // Ignore objects which are too close
 			float3 color = ColorTexture.SampleLevel(LinearSampler, uv, 0);
-			float4 output = float4(sRGB2Lin(color), 1.0);
+			float4 output = float4(color, 1.0);
 			float lerpFactor = 1.0 / 64.0;
 
 			half4 positionCS = half4(2 * half2(uv.x, -uv.y + 1) - 1, depth, 1);

features/Screen Space GI/Shaders/ScreenSpaceGI/radianceDisocc.cs.hlsl

@@ -131,7 +131,7 @@ void readHistory(
 
 	half3 radiance = 0;
 #ifdef GI
-	radiance = sRGB2Lin(FULLRES_LOAD(srcDiffuse, pixCoord, uv * frameScale, samplerLinearClamp).rgb * GIStrength);
+	radiance = FULLRES_LOAD(srcDiffuse, pixCoord, uv * frameScale, samplerLinearClamp).rgb * GIStrength;
 #	ifdef GI_BOUNCE
 	radiance += prev_ambient.rgb * GIBounceFade;
 #	endif

features/Subsurface Scattering/Shaders/SubsurfaceScattering/SeparableSSS.hlsli

@@ -99,10 +99,6 @@ float4 SSSSBlurCS(
 	// Fetch color of current pixel:
 	float4 colorM = ColorTexture[DTid.xy];
 
-#if defined(HORIZONTAL)
-	colorM.rgb = sRGB2Lin(colorM.rgb);
-#endif
-
 	if (sssAmount == 0)
 		return colorM;
 
@@ -156,10 +152,6 @@ float4 SSSSBlurCS(
 
 		float3 color = ColorTexture[coords].rgb;
 
-#if defined(HORIZONTAL)
-		color.rgb = sRGB2Lin(color.rgb);
-#endif
-
 		float depth = DepthTexture[coords].r;
 		depth = GetScreenDepth(depth);
 

features/Subsurface Scattering/Shaders/SubsurfaceScattering/SeparableSSSCS.hlsl

@@ -39,7 +39,6 @@ cbuffer PerFrameSSS : register(b1)
 	bool humanProfile = MaskTexture[DTid.xy].y == sssAmount;
 
 	float4 color = SSSSBlurCS(DTid.xy, texCoord, float2(0.0, 1.0), sssAmount, humanProfile);
-	color.rgb = Lin2sRGB(color.rgb);
 	SSSRW[DTid.xy] = float4(color.rgb, 1.0);
 
 #endif

features/Wetness Effects/Shaders/WetnessEffects/WetnessEffects.hlsli

@@ -144,7 +144,7 @@ float3 GetWetnessAmbientSpecular(float2 uv, float3 N, float3 VN, float3 V, float
 	float3 specularIrradiance = 1.0;
 #	else
 	float level = roughness * 7.0;
-	float3 specularIrradiance = sRGB2Lin(specularTexture.SampleLevel(SampColorSampler, R, level));
+	float3 specularIrradiance = specularTexture.SampleLevel(SampColorSampler, R, level);
 #	endif
 #else
 	float3 specularIrradiance = 1.0;

package/Shaders/AmbientCompositeCS.hlsl

@@ -51,11 +51,7 @@ RWTexture2D<half3> DiffuseAmbientRW : register(u1);
 
 	half3 directionalAmbientColor = mul(DirectionalAmbient, half4(normalWS, 1.0));
 
-	half3 linAlbedo = sRGB2Lin(albedo);
-	half3 linDirectionalAmbientColor = sRGB2Lin(directionalAmbientColor);
-	half3 linDiffuseColor = sRGB2Lin(diffuseColor);
-
-	half3 linAmbient = lerp(sRGB2Lin(albedo * directionalAmbientColor), linAlbedo * linDirectionalAmbientColor, pbrWeight);
+	half3 ambient = albedo * directionalAmbientColor;
 
 	half visibility = 1.0;
 #if defined(SKYLIGHTING)
@@ -76,24 +72,23 @@ RWTexture2D<half3> DiffuseAmbientRW : register(u1);
 
 #if defined(SSGI)
 	half4 ssgiDiffuse = SSGITexture[dispatchID.xy];
-	ssgiDiffuse.rgb *= linAlbedo;
+	ssgiDiffuse.rgb *= albedo;
 	ssgiDiffuse.a = 1 - ssgiDiffuse.a;
 
 	visibility *= ssgiDiffuse.a;
 
-	DiffuseAmbientRW[dispatchID.xy] = linAlbedo * linDirectionalAmbientColor + ssgiDiffuse.rgb;
+	DiffuseAmbientRW[dispatchID.xy] = albedo * directionalAmbientColor + ssgiDiffuse.rgb;
 
 #	if defined(INTERIOR)
-	linDiffuseColor *= ssgiDiffuse.a;
+	diffuseColor *= ssgiDiffuse.a;
 #	endif
-	linDiffuseColor += ssgiDiffuse.rgb;
+	diffuseColor += ssgiDiffuse.rgb;
 #endif
 
-	linAmbient *= visibility;
-	diffuseColor = Lin2sRGB(linDiffuseColor);
-	directionalAmbientColor = Lin2sRGB(linDirectionalAmbientColor * visibility);
+	ambient *= visibility;
+	directionalAmbientColor = directionalAmbientColor * visibility;
 
-	diffuseColor = lerp(diffuseColor + directionalAmbientColor * albedo, Lin2sRGB(linDiffuseColor + linAmbient), pbrWeight);
+	diffuseColor = diffuseColor + directionalAmbientColor * albedo;
 
 	MainRW[dispatchID.xy] = diffuseColor;
 };

package/Shaders/Common/PBR.hlsli

@@ -43,17 +43,17 @@ namespace PBR
 
 	float3 AdjustDirectionalLightColor(float3 lightColor)
 	{
-		return pbrSettings.DirectionalLightColorMultiplier * sRGB2Lin(lightColor);
+		return pbrSettings.DirectionalLightColorMultiplier * lightColor;
 	}
 
 	float3 AdjustPointLightColor(float3 lightColor)
 	{
-		return pbrSettings.PointLightColorMultiplier * sRGB2Lin(lightColor);
+		return pbrSettings.PointLightColorMultiplier * lightColor;
 	}
 
 	float3 AdjustAmbientLightColor(float3 lightColor)
 	{
-		return pbrSettings.AmbientLightColorMultiplier * sRGB2Lin(lightColor);
+		return pbrSettings.AmbientLightColorMultiplier * lightColor;
 	}
 
 	// [Jimenez et al. 2016, "Practical Realtime Strategies for Accurate Indirect Occlusion"]

package/Shaders/DeferredCompositeCS.hlsl

@@ -60,7 +60,7 @@ Texture2D<half4> SpecularSSGITexture : register(t10);
 
 	half glossiness = normalGlossiness.z;
 
-	half3 color = lerp(diffuseColor + specularColor, Lin2sRGB(sRGB2Lin(diffuseColor) + sRGB2Lin(specularColor)), pbrWeight);
+	half3 color = diffuseColor + specularColor;
 
 #if defined(DYNAMIC_CUBEMAPS)
 
@@ -73,8 +73,6 @@ Texture2D<half4> SpecularSSGITexture : register(t10);
 
 		normalWS = lerp(normalWS, float3(0, 0, 1), wetnessMask);
 
-		color = sRGB2Lin(color);
-
 		half depth = DepthTexture[dispatchID.xy];
 
 		half4 positionCS = half4(2 * half2(uv.x, -uv.y + 1) - 1, depth, 1);
@@ -89,12 +87,12 @@ Texture2D<half4> SpecularSSGITexture : register(t10);
 		half roughness = 1.0 - glossiness;
 		half level = roughness * 7.0;
 
-		half3 directionalAmbientColor = sRGB2Lin(mul(DirectionalAmbient, half4(R, 1.0)));
+		half3 directionalAmbientColor = mul(DirectionalAmbient, half4(R, 1.0));
 		half3 finalIrradiance = 0;
 
 #	if defined(INTERIOR)
 		half3 specularIrradiance = EnvTexture.SampleLevel(LinearSampler, R, level).xyz;
-		specularIrradiance = sRGB2Lin(specularIrradiance);
+		specularIrradiance = specularIrradiance;
 
 		finalIrradiance += specularIrradiance;
 #	elif defined(SKYLIGHTING)
@@ -114,19 +112,19 @@ Texture2D<half4> SpecularSSGITexture : register(t10);
 
 		if (skylightingSpecular < 1.0) {
 			specularIrradiance = EnvTexture.SampleLevel(LinearSampler, R, level).xyz;
-			specularIrradiance = sRGB2Lin(specularIrradiance);
+			specularIrradiance = specularIrradiance;
 		}
 
 		half3 specularIrradianceReflections = 1.0;
 
 		if (skylightingSpecular > 0.0) {
 			specularIrradianceReflections = EnvReflectionsTexture.SampleLevel(LinearSampler, R, level).xyz;
-			specularIrradianceReflections = sRGB2Lin(specularIrradianceReflections);
+			specularIrradianceReflections = specularIrradianceReflections;
 		}
 		finalIrradiance = finalIrradiance * skylightingSpecular + lerp(specularIrradiance, specularIrradianceReflections, skylightingSpecular);
 #	else
 		half3 specularIrradianceReflections = EnvReflectionsTexture.SampleLevel(LinearSampler, R, level).xyz;
-		specularIrradianceReflections = sRGB2Lin(specularIrradianceReflections);
+		specularIrradianceReflections = specularIrradianceReflections;
 
 		finalIrradiance += specularIrradianceReflections;
 #	endif
@@ -137,8 +135,6 @@ Texture2D<half4> SpecularSSGITexture : register(t10);
 #	endif
 
 		color += reflectance * finalIrradiance;
-
-		color = Lin2sRGB(color);
 	}
 
 #endif

package/Shaders/Lighting.hlsl

@@ -1578,6 +1578,8 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 	float3 screenSpaceNormal = normalize(WorldToView(worldSpaceNormal, false, eyeIndex));
 
 #	if defined(TRUE_PBR)
+	baseColor.xyz = Lin2sRGB(baseColor.xyz);
+
 	PBR::SurfaceProperties pbrSurfaceProperties;
 
 	pbrSurfaceProperties.Roughness = saturate(rawRMAOS.x);
@@ -1966,7 +1968,7 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 
 #		if defined(WETNESS_EFFECTS)
 	if (waterRoughnessSpecular < 1.0)
-		wetnessSpecular += GetWetnessSpecular(wetnessNormal, normalizedDirLightDirectionWS, worldSpaceViewDirection, sRGB2Lin(dirLightColor * dirDetailShadow), waterRoughnessSpecular);
+		wetnessSpecular += GetWetnessSpecular(wetnessNormal, normalizedDirLightDirectionWS, worldSpaceViewDirection, dirLightColor * dirDetailShadow, waterRoughnessSpecular);
 #		endif
 #	endif
 
@@ -2175,7 +2177,7 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 
 #			if defined(WETNESS_EFFECTS)
 		if (waterRoughnessSpecular < 1.0)
-			wetnessSpecular += GetWetnessSpecular(wetnessNormal, normalizedLightDirection, worldSpaceViewDirection, sRGB2Lin(lightColor), waterRoughnessSpecular);
+			wetnessSpecular += GetWetnessSpecular(wetnessNormal, normalizedLightDirection, worldSpaceViewDirection, lightColor, waterRoughnessSpecular);
 #			endif
 	}
 #		endif
@@ -2228,13 +2230,8 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 #	if defined(SKYLIGHTING)
 	float skylightingDiffuse = shFuncProductIntegral(skylightingSH, shEvaluateCosineLobe(skylightingSettings.DirectionalDiffuse ? worldSpaceNormal : float3(0, 0, 1))) / shPI;
 	skylightingDiffuse = Skylighting::mixDiffuse(skylightingSettings, skylightingDiffuse);
-#		if !defined(TRUE_PBR)
-	directionalAmbientColor = sRGB2Lin(directionalAmbientColor);
-#		endif
+
 	directionalAmbientColor *= skylightingDiffuse;
-#		if !defined(TRUE_PBR)
-	directionalAmbientColor = Lin2sRGB(directionalAmbientColor);
-#		endif
 #	endif
 
 #	if defined(TRUE_PBR) && defined(LOD_LAND_BLEND) && !defined(DEFERRED)
@@ -2264,7 +2261,7 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 		dynamicCubemap = true;
 		envColorBase = TexEnvSampler.SampleLevel(SampEnvSampler, float3(1.0, 0.0, 0.0), 0);
 		if (envColorBase.a < 1.0) {
-			F0 = sRGB2Lin(envColorBase.rgb) + sRGB2Lin(baseColor.rgb);
+			F0 = envColorBase.rgb + baseColor.rgb;
 			envRoughness = envColorBase.a;
 		} else {
 			F0 = 1.0;
@@ -2275,7 +2272,7 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 #			if defined(CREATOR)
 	if (cubemapCreatorSettings.Enabled) {
 		dynamicCubemap = true;
-		F0 = sRGB2Lin(cubemapCreatorSettings.CubemapColor.rgb) + sRGB2Lin(baseColor.xyz);
+		F0 = cubemapCreatorSettings.CubemapColor.rgb + baseColor.xyz;
 		envRoughness = cubemapCreatorSettings.CubemapColor.a;
 	}
 #			endif
@@ -2284,7 +2281,7 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 #			if defined(EMAT)
 		envRoughness = lerp(envRoughness, 1.0 - complexMaterialColor.y, (float)complexMaterial);
 		envRoughness *= envRoughness;
-		F0 = lerp(F0, sRGB2Lin(complexSpecular), (float)complexMaterial);
+		F0 = lerp(F0, complexSpecular, (float)complexMaterial);
 #			endif
 
 		envColor = GetDynamicCubemap(screenUV, worldSpaceNormal, worldSpaceVertexNormal, worldSpaceViewDirection, envRoughness, F0, diffuseColor, viewPosition.z) * envMask;
@@ -2413,7 +2410,6 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 #			else
 		diffuseColor = 1.0;
 #			endif
-		specularColor = sRGB2Lin(specularColor);
 	}
 #		endif
 
@@ -2428,10 +2424,6 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 #		else
 	specularColor += envColor * diffuseColor;
 #		endif
-#		if defined(DYNAMIC_CUBEMAPS)
-	if (dynamicCubemap)
-		specularColor = Lin2sRGB(specularColor);
-#		endif
 #	endif
 
 #	if defined(EMAT) && defined(ENVMAP)
@@ -2442,8 +2434,6 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 #		if !defined(DEFERRED)
 	color.xyz += specularColor;
 #		endif
-
-	color.xyz = sRGB2Lin(color.xyz);
 #	endif
 
 #	if defined(WETNESS_EFFECTS) && !defined(TRUE_PBR)
@@ -2454,8 +2444,6 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 	color.xyz += specularColorPBR;
 #	endif
 
-	color.xyz = Lin2sRGB(color.xyz);
-
 #	if defined(LOD_LAND_BLEND) && defined(TRUE_PBR)
 	{
 		pbrWeight = 1 - lodLandBlendFactor;
@@ -2465,7 +2453,7 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 
 #		if defined(DEFERRED)
 		specularColorPBR = lerp(specularColorPBR, 0, lodLandBlendFactor);
-		indirectDiffuseLobeWeight = lerp(indirectDiffuseLobeWeight, sRGB2Lin(input.Color.xyz * lodLandColor * lodLandFadeFactor), lodLandBlendFactor);
+		indirectDiffuseLobeWeight = lerp(indirectDiffuseLobeWeight, input.Color.xyz * lodLandColor * lodLandFadeFactor, lodLandBlendFactor);
 		indirectSpecularLobeWeight = lerp(indirectSpecularLobeWeight, 0, lodLandBlendFactor);
 		pbrGlossiness = lerp(pbrGlossiness, 0, lodLandBlendFactor);
 #		endif
@@ -2606,13 +2594,13 @@ PS_OUTPUT main(PS_INPUT input, bool frontFace
 
 	float3 outputSpecular = specularColor.xyz;
 #		if defined(TRUE_PBR)
-	outputSpecular = Lin2sRGB(specularColorPBR.xyz);
+	outputSpecular = specularColorPBR.xyz;
 #		endif
 	psout.Specular = float4(outputSpecular, psout.Diffuse.w);
 
 	float3 outputAlbedo = baseColor.xyz * vertexColor;
 #		if defined(TRUE_PBR)
-	outputAlbedo = Lin2sRGB(indirectDiffuseLobeWeight);
+	outputAlbedo = indirectDiffuseLobeWeight;
 #		endif
 	psout.Albedo = float4(outputAlbedo, psout.Diffuse.w);