Improve color handling approach

src/graphics/rendering/shaders/distance-fs-100.glsl

@@ -6,17 +6,23 @@ uniform float maxMinDistance;
 uniform float distanceNdcPixelSize;
 varying vec2 position;
 
+uniform sampler2D palette;
+
+vec4 readFromPalette(int index) {
+  return texture2D(palette, vec2((float(index) + 0.5) / {paletteSize}, 0.5));
+}
+
+
 {macroDefinitions}
 
 {declarations}
 
 void main() {
-    float minDistance = maxMinDistance;
-    float color = 0.0;
-
-    float objectMinDistance, objectColor;
+    float minDistance = maxMinDistance, objectMinDistance;
+    vec4 color = {backgroundColor};
+    vec4 objectColor;
 
     {functionCalls}
     
-    gl_FragColor = vec4(minDistance * 8.0, color, 0.0, 1.0);
+    gl_FragColor = vec4(color.rgb, minDistance * 8.0);
 }

src/graphics/rendering/shaders/distance-fs.glsl

@@ -6,21 +6,28 @@ uniform float maxMinDistance;
 uniform float distanceNdcPixelSize;
 in vec2 position;
 
+uniform sampler2D palette;
+
 #define WEBGL2_IS_AVAILABLE
 
+vec4 readFromPalette(int index) {
+  return texture(palette, vec2((float(index) + 0.5) / {paletteSize}, 0.5));
+}
+
 {macroDefinitions}
 
 {declarations}
 
-out vec2 fragmentColor;
+layout(location = 0) out vec4 fragmentColor;
+layout(location = 1) out float distanceValue;
 
 void main() {
-    float minDistance = maxMinDistance;
-    float color = 0.0;
-
-    float objectMinDistance, objectColor;
+    float minDistance = maxMinDistance, objectMinDistance;
+    vec4 color = {backgroundColor};
+    vec4 objectColor;
 
     {functionCalls}
 
-    fragmentColor = vec2(minDistance, color);
+    distanceValue = minDistance;
+    fragmentColor = color;
 }

src/graphics/rendering/shaders/shading-fs-100.glsl

@@ -10,22 +10,20 @@ precision lowp float;
 uniform float shadingNdcPixelSize;
 uniform vec2 squareToAspectRatioTimes2;
 uniform vec3 ambientLight;
-uniform vec4 backgroundColor;
 
-uniform sampler2D distanceTexture;
-uniform sampler2D palette;
+uniform sampler2D colorTexture;
 
 varying vec2 position;
 varying vec2 uvCoordinates;
 
 float getDistance(in vec2 target, out vec4 color) {
-    vec4 values = texture2D(distanceTexture, target);
-    color = texture2D(palette, vec2(values[1], 0.0));
-    return values[0] / 8.0;
+    vec4 values = texture2D(colorTexture, target);
+    color = vec4(values.rgb, 1.0);
+    return values[3] / 8.0;
 }
 
 float getDistance(in vec2 target) {
-    return texture2D(distanceTexture, target)[0] / 8.0;
+    return texture2D(colorTexture, target)[3] / 8.0;
 }
 
 float shadowTransparency(float startingDistance, float lightCenterDistance, vec2 direction) {
@@ -122,13 +120,13 @@ void main() {
     #endif
     #endif
 
-    vec3 outsideColor = backgroundColor.rgb * lighting;
+    vec3 outsideColor = {backgroundColor}.rgb * lighting;
     vec3 insideColor = colorAtPosition * lightingInside;
 
     float edge = clamp(startingDistance / shadingNdcPixelSize, 0.0, 1.0);
     vec3 antialiasedColor = mix(insideColor, outsideColor, edge);
     gl_FragColor = vec4(
         antialiasedColor,
-        mix(rgbaColorAtPosition.a, backgroundColor.a, step(0.0, startingDistance))
+        rgbaColorAtPosition.a
     );
 }

src/graphics/rendering/shaders/shading-fs.glsl

@@ -8,23 +8,21 @@ precision lowp float;
 {macroDefinitions}
 
 uniform float shadingNdcPixelSize;
+uniform float distanceNdcPixelSize;
 uniform vec2 squareToAspectRatioTimes2;
 uniform vec3 ambientLight;
-uniform vec4 backgroundColor;
 
 uniform sampler2D distanceTexture;
-uniform sampler2D palette;
+uniform sampler2D colorTexture;
 
 in vec2 position;
 in vec2 uvCoordinates;
 
-float getDistance(in vec2 target, out vec4 color) {
-    vec4 values = texture(distanceTexture, target);
-    color = texture(palette, vec2(values[1], 0.0));
-    return values[0];
+vec4 getColor(vec2 target) {
+    return texture(colorTexture, target);
 }
 
-float getDistance(in vec2 target) {
+float getDistance(vec2 target) {
     return texture(distanceTexture, target)[0];
 }
 
@@ -83,13 +81,14 @@ float shadowTransparency(float startingDistance, float lightCenterDistance, vec2
 
 out vec4 fragmentColor;
 void main() {
-    vec4 rgbaColorAtPosition;
-    float startingDistance = getDistance(uvCoordinates, rgbaColorAtPosition);
-
+    vec4 rgbaColorAtPosition = getColor(uvCoordinates);
     vec3 colorAtPosition = rgbaColorAtPosition.rgb;
 
+    float startingDistance = getDistance(uvCoordinates);
+
+
     vec3 lighting = ambientLight;
-    vec3 lightingInside = lighting;
+    vec3 lightingInside = ambientLight;
     
     #ifdef CIRCLE_LIGHT_COUNT
     #if CIRCLE_LIGHT_COUNT > 0
@@ -142,13 +141,13 @@ void main() {
     #endif
     #endif
 
-    vec3 outsideColor = backgroundColor.rgb * lighting;
+    vec3 outsideColor = {backgroundColor}.rgb * lighting;
     vec3 insideColor = colorAtPosition * lightingInside * INTENSITY_INSIDE_RATIO;
-
+    
     float edge = clamp(startingDistance / shadingNdcPixelSize, 0.0, 1.0);
     vec3 antialiasedColor = mix(insideColor, outsideColor, edge);
     fragmentColor = vec4(
         antialiasedColor,
-        mix(rgbaColorAtPosition.a, backgroundColor.a, step(0.0, startingDistance))
+        rgbaColorAtPosition.a
     );
 }