Convert fogball calculations from sRGB to linear

MrRaveYard · Jan 10, 2024 · 4858dea · 4858dea
1 parent 62be7a5
commit 4858dea
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Showing 2 changed files with 8 additions and 2 deletions.
diff --git a/src/rendering/hwrenderer/scene/hw_sprites.cpp b/src/rendering/hwrenderer/scene/hw_sprites.cpp
@@ -774,7 +774,7 @@ void HWSprite::Process(HWDrawInfo *di, FRenderState& state, AActor* thing, secto
 		Fogball fogball;
 		fogball.Position = FVector3(thing->Pos());
 		fogball.Radius = (float)thing->args[3];
-		fogball.Color = FVector3(thing->args[0] * (1.0f / 255.0f), thing->args[1] * (1.0f / 255.0f), thing->args[2] * (1.0f / 255.0f));
+		fogball.Color = FVector3(powf(thing->args[0] * (1.0f / 255.0f), 2.2), powf(thing->args[1] * (1.0f / 255.0f), 2.2), powf(thing->args[2] * (1.0f / 255.0f), 2.2));
 		fogball.Fog = (float)thing->Alpha;
 		di->Fogballs.Push(fogball);
 		return;

diff --git a/wadsrc/static/shaders/scene/fogball.glsl b/wadsrc/static/shaders/scene/fogball.glsl
@@ -40,8 +40,14 @@ float FogSphereDensity(vec3 rayOrigin, vec3 rayDirection, vec3 sphereCenter, flo
 	return (i2 - i1) * (3.0f / 4.0f);
 }
 
+// Approximate sRGB/linear conversion
+vec3 ToLinear(vec3 c) { return pow(c, vec3(2.2)); }
+vec3 FromLinear(vec3 c) { return pow(c, vec3(1.0 / 2.2)); }
+
 vec4 ProcessFogBalls(vec4 light)
 {
+	light.rgb = ToLinear(light.rgb);
+
 	vec3 rayOrigin = uCameraPos.xyz;
 	float dbuffer = distance(pixelpos.xyz, uCameraPos.xyz);
 	vec3 rayDirection = normalize(pixelpos.xyz - uCameraPos.xyz);
@@ -59,5 +65,5 @@ vec4 ProcessFogBalls(vec4 light)
 		light.rgb = mix(light.rgb, fogcolor * density, alpha);
 	}
 
-	return light;
+	return vec4(FromLinear(light.rgb), light.a);
 }