From 0ad339d4c4d5e50971bd9a614cd774dc2b8a81f0 Mon Sep 17 00:00:00 2001
From: Leon Styhre <leon@leonstyhre.com>
Date: Mon, 12 Dec 2022 20:21:22 +0100
Subject: [PATCH] Fixed an issue where lowered saturation could not be combined
 with color shifts.

---
 resources/shaders/glsl/core.glsl | 28 ++++++++++++++--------------
 1 file changed, 14 insertions(+), 14 deletions(-)

diff --git a/resources/shaders/glsl/core.glsl b/resources/shaders/glsl/core.glsl
index 22fb53cfc..2bcd22374 100644
--- a/resources/shaders/glsl/core.glsl
+++ b/resources/shaders/glsl/core.glsl
@@ -4,7 +4,7 @@
 //  core.glsl
 //
 //  Core shader functionality:
-//  Clipping, opacity, saturation, dimming and reflections falloff.
+//  Clipping, saturation, opacity, dimming and reflections falloff.
 //
 
 // Vertex section of code:
@@ -39,8 +39,8 @@ in vec2 texCoord;
 in vec4 color;
 
 uniform vec4 clipRegion;
-uniform float opacity;
 uniform float saturation;
+uniform float opacity;
 uniform float dimming;
 uniform float reflectionsFalloff;
 uniform uint shaderFlags;
@@ -70,6 +70,18 @@ void main()
 
     vec4 sampledColor = texture(textureSampler, texCoord);
 
+    // Saturation.
+    if (saturation != 1.0) {
+        vec3 grayscale;
+        // Premultiplied textures are all in BGRA format.
+        if (0x0u != (shaderFlags & 0x01u))
+            grayscale = vec3(dot(sampledColor.bgr, vec3(0.0721, 0.7154, 0.2125)));
+        else
+            grayscale = vec3(dot(sampledColor.rgb, vec3(0.2125, 0.7154, 0.0721)));
+        vec3 blendedColor = mix(grayscale, sampledColor.rgb, saturation);
+        sampledColor = vec4(blendedColor, sampledColor.a);
+    }
+
     // For fonts the alpha information is stored in the red channel.
     if (0x0u != (shaderFlags & 0x2u))
         sampledColor = vec4(1.0, 1.0, 1.0, sampledColor.r);
@@ -97,18 +109,6 @@ void main()
             sampledColor *= opacity;
     }
 
-    // Saturation.
-    if (saturation != 1.0) {
-        vec3 grayscale;
-        // Premultiplied textures are all in BGRA format.
-        if (0x0u != (shaderFlags & 0x01u))
-            grayscale = vec3(dot(sampledColor.bgr, vec3(0.34, 0.55, 0.11)));
-        else
-            grayscale = vec3(dot(sampledColor.rgb, vec3(0.34, 0.55, 0.11)));
-        vec3 blendedColor = mix(grayscale, sampledColor.rgb, saturation);
-        sampledColor = vec4(blendedColor, sampledColor.a);
-    }
-
     // Dimming.
     if (dimming != 1.0) {
         vec4 dimColor = vec4(dimming, dimming, dimming, 1.0);