Added support for changing the saturation for font textures.

es-core/src/components/TextComponent.cpp

@@ -115,6 +115,13 @@ void TextComponent::setOpacity(float opacity)
         mTextCache->setOpacity(mThemeOpacity);
 }
 
+void TextComponent::setSaturation(float saturation)
+{
+    mSaturation = saturation;
+    if (mTextCache)
+        mTextCache->setSaturation(saturation);
+}
+
 void TextComponent::setDimming(float dimming)
 {
     mDimming = dimming;

es-core/src/components/TextComponent.h

@@ -62,6 +62,7 @@ public:
     float const getColorOpacity() const override { return mColorOpacity; }
 
     void setOpacity(float opacity) override;
+    void setSaturation(float saturation) override;
     void setDimming(float dimming) override;
 
     void setSelectable(bool status) { mSelectable = status; }

es-core/src/resources/Font.cpp

@@ -826,6 +826,14 @@ void TextCache::setOpacity(float opacity)
     }
 }
 
+void TextCache::setSaturation(float saturation)
+{
+    for (auto it = vertexLists.begin(); it != vertexLists.end(); ++it) {
+        for (auto it2 = it->verts.begin(); it2 != it->verts.end(); ++it2)
+            it2->saturation = saturation;
+    }
+}
+
 void TextCache::setDimming(float dimming)
 {
     for (auto it = vertexLists.begin(); it != vertexLists.end(); ++it) {

es-core/src/resources/Font.h

@@ -238,6 +238,7 @@ public:
 
     void setColor(unsigned int color);
     void setOpacity(float opacity);
+    void setSaturation(float saturation);
     void setDimming(float dimming);
 
     friend Font;

resources/shaders/glsl/core.glsl

@@ -79,8 +79,8 @@ void main()
         sampledColor.rgb *= sampledColor.a;
     }
 
-    // Saturation.
+    // Saturation, except for font textures.
-    if (saturation != 1.0) {
+    if (saturation != 1.0 && 0x0u == (shaderFlags & 0x2u)) {
         vec3 grayscale;
         // Premultiplied textures are all in BGRA format.
         if (0x0u != (shaderFlags & 0x01u))
@@ -105,6 +105,13 @@ void main()
         sampledColor *= color;
     }
 
+    // Saturation for font textures.
+    if (saturation != 1.0 && 0x0u != (shaderFlags & 0x2u)) {
+        vec3 grayscale = vec3(dot(sampledColor.rgb, vec3(0.299, 0.587, 0.114)));
+        vec3 blendedColor = mix(grayscale, sampledColor.rgb, saturation);
+        sampledColor = vec4(blendedColor, sampledColor.a);
+    }
+
     // When post-processing we drop the alpha channel to avoid strange issues with some
     // graphics drivers.
     if (0x0u != (shaderFlags & 0x4u))