dithered skybox

assets/4096_bayer.frag

@@ -3,25 +3,29 @@ varying vec2 v_texCoords;
 uniform sampler2D u_texture;
 
 
+// "steps" of R, G and B. Must be integer && equal or greater than 2
+uniform float rcount = 4.0;
+uniform float gcount = 4.0;
+uniform float bcount = 4.0;
+uniform float acount = 1.0;
+
 
-//uniform mat4 bayer;
-uniform float monitorGamma; // give 2.2f
 
 int bayer[8][8] = {
-{ 0, 32, 8, 40, 2, 34, 10, 42},   // 8x8 bayer ordered dithering
-{48, 16, 56, 24, 50, 18, 58, 26}, // pattern. Each input pixel
-{12, 44, 4, 36, 14, 46, 6, 38},   // is scaled to the 0..63 range
-{60, 28, 52, 20, 62, 30, 54, 22}, // before looking in this table
-{ 3, 35, 11, 43, 1, 33, 9, 41},   // to determine the action
-{51, 19, 59, 27, 49, 17, 57, 25},
-{15, 47, 7, 39, 13, 45, 5, 37},
-{63, 31, 55, 23, 61, 29, 53, 21} }; // fun fact: you can calculate bayer value on-the-fly but LUT is faster
+{ 0,32, 8,40, 2,34,10,42}, // 8x8 bayer ordered dithering
+{48,16,56,24,50,18,58,26}, // pattern. Each input pixel
+{12,44, 4,36,14,46, 6,38}, // is scaled to the 0..63 range
+{60,28,52,20,62,30,54,22}, // before looking in this table
+{ 3,35,11,43, 1,33, 9,41}, // to determine the action
+{51,19,59,27,49,17,57,25},
+{15,47, 7,39,13,45, 5,37},
+{63,31,55,23,61,29,53,21} }; // fun fact: you can calculate bayer value on-the-fly but LUT is faster
 float bayerSize = 8.0;
 float bayerDivider = bayerSize * bayerSize;
 
 
 vec4 nearestColour(vec4 incolor) {
-    vec4 rgbaCounts = vec4(16.0, 16.0, 16.0, 1.0);
+    vec4 rgbaCounts = vec4(rcount, gcount, bcount, acount);
 
 
     vec4 color = incolor;
@@ -33,9 +37,6 @@ vec4 nearestColour(vec4 incolor) {
     if (rgbaCounts.a >= 2.0) {
         color.a = floor((rgbaCounts.a - 1.0) * color.a + 0.5) / (rgbaCounts.a - 1.0);
     }
-    else if (rgbaCounts.a == 1.0) {
-        color.a = (color.a >= 0.5f) ? 1.0 : 0.0;
-    }
     else {
         color.a = 1.0;
     }
@@ -44,13 +45,14 @@ vec4 nearestColour(vec4 incolor) {
 }
 
 void main(void) {
+    float spread = 1.0 / (0.299 * (rcount - 1.0) + 0.587 * (gcount - 1.0) + 0.114 * (bcount - 1.0));  // this spread value is optimised one -- try your own values for various effects!
+
+
     // create texture coordinates based on pixelSize //
     vec4 inColor = texture2D(u_texture, v_texCoords);
 
     vec2 entry = mod(gl_FragCoord.xy, vec2(bayerSize, bayerSize));
 
-    float r = 1.0 / monitorGamma;
-
-    gl_FragColor = nearestColour(inColor + r * (bayer[int(entry.y)][int(entry.x)] / bayerDivider - 0.5));
+    gl_FragColor = nearestColour(inColor + spread * (bayer[int(entry.y)][int(entry.x)] / bayerDivider - 0.5));
     //gl_FragColor = nearestColour(inColor);
 }

assets/4096_bayer_skyboxfill.frag

@@ -0,0 +1,58 @@
+varying vec4 v_color;
+varying vec2 v_texCoords;
+uniform sampler2D u_texture;
+
+
+uniform vec3 topColor;
+uniform vec3 bottomColor;
+uniform float screenHeight;
+
+
+// "steps" of R, G and B. Must be integer && equal or greater than 2
+uniform float rcount = 256.0; // it even works on 256.0!
+uniform float gcount = 256.0;
+uniform float bcount = 256.0;
+
+
+
+int bayer[8][8] = {
+{ 0,32, 8,40, 2,34,10,42}, // 8x8 bayer ordered dithering
+{48,16,56,24,50,18,58,26}, // pattern. Each input pixel
+{12,44, 4,36,14,46, 6,38}, // is scaled to the 0..63 range
+{60,28,52,20,62,30,54,22}, // before looking in this table
+{ 3,35,11,43, 1,33, 9,41}, // to determine the action
+{51,19,59,27,49,17,57,25},
+{15,47, 7,39,13,45, 5,37},
+{63,31,55,23,61,29,53,21} }; // fun fact: you can calculate bayer value on-the-fly but LUT is faster
+float bayerSize = 8.0;
+float bayerDivider = bayerSize * bayerSize;
+
+
+vec4 nearestColour(vec4 incolor) {
+    vec4 rgbaCounts = vec4(rcount, gcount, bcount, 1.0);
+
+
+    vec4 color = incolor;
+
+    color.r = floor((rgbaCounts.r - 1.0) * color.r + 0.5) / (rgbaCounts.r - 1.0);
+    color.g = floor((rgbaCounts.g - 1.0) * color.g + 0.5) / (rgbaCounts.g - 1.0);
+    color.b = floor((rgbaCounts.b - 1.0) * color.b + 0.5) / (rgbaCounts.b - 1.0);
+    color.a = 1.0;
+
+    return color;
+}
+
+void main(void) {
+    float spread = 1.0 / (0.299 * (rcount - 1.0) + 0.587 * (gcount - 1.0) + 0.114 * (bcount - 1.0));  // this spread value is optimised one -- try your own values for various effects!
+
+    float scale = v_texCoords.y; // screenHeight;
+    float inR = mix(bottomColor.r, topColor.r, scale);
+    float inG = mix(bottomColor.g, topColor.g, scale);
+    float inB = mix(bottomColor.b, topColor.b, scale);
+
+    vec4 inColor = vec4(inR, inG, inB, 1.0);
+
+    vec2 entry = mod(gl_FragCoord.xy, vec2(bayerSize, bayerSize));
+
+    gl_FragColor = nearestColour(inColor + spread * (bayer[int(entry.y)][int(entry.x)] / bayerDivider - 0.5));
+}