Improve effects shader when fog is enabled

Fix visual artifacts with premultiplied effect textures and improve additive blending when fog is enabled.
Warzone2100 · Jul 22, 2024 · 15d2519 · 15d2519
1 parent 9bc3f31
commit 15d2519
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Showing 2 changed files with 8 additions and 2 deletions.
diff --git a/data/base/shaders/nolight_instanced.frag b/data/base/shaders/nolight_instanced.frag
@@ -60,7 +60,10 @@ void main()
 		}
 
 		// Return fragment color
-		fragColour = mix(fragColour, vec4(fogColor.xyz, fragColour.w), clamp(fogFactor, 0.0, 1.0));
+		vec3 fogPremultAlphaFactor = mix(vec3(fragColour.a), vec3(1.f,1.f,1.f), vec3(float(alphaTest)));
+		float fogFactorAdjust = mix(1.f, 0.f, float(alphaTest));
+		fragColour = vec4(mix(fragColour.rgb, fogColor.rgb * fogPremultAlphaFactor, clamp(fogFactor * fogFactorAdjust, 0.0, 1.0)), fragColour.a);
+		fragColour.a = fragColour.a * (1.0 - clamp(fogFactor, 0.0, 1.0));
 	}
 
 	#ifdef NEWGL

diff --git a/data/base/shaders/vk/nolight_instanced.frag b/data/base/shaders/vk/nolight_instanced.frag
@@ -40,7 +40,10 @@ void main()
 		}
 
 		// Return fragment color
-		fragColour = mix(fragColour, vec4(fogColor.xyz, fragColour.w), clamp(fogFactor, 0.0, 1.0));
+		vec3 fogPremultAlphaFactor = mix(vec3(fragColour.a), vec3(1.f,1.f,1.f), vec3(float(alphaTest)));
+		float fogFactorAdjust = mix(1.f, 0.f, float(alphaTest));
+		fragColour = vec4(mix(fragColour.rgb, fogColor.rgb * fogPremultAlphaFactor, clamp(fogFactor * fogFactorAdjust, 0.0, 1.0)), fragColour.a);
+		fragColour.a = fragColour.a * (1.0 - clamp(fogFactor, 0.0, 1.0));
 	}
 
 	FragColor = fragColour;