voronoise

06/TODO.md

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+Add some references and ideas from this IQ article: http://iquilezles.org/www/articles/palettes/palettes.htm 

11/2d-voronoise.frag

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+#ifdef GL_ES
+precision mediump float;
+#endif
+
+uniform vec2 u_resolution;
+uniform vec2 u_mouse;
+uniform float u_time;
+
+// Created by inigo quilez - iq/2013
+// License Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
+// http://iquilezles.org/www/articles/voronoise/voronoise.htm
+vec3 hash3( vec2 p ) {
+    vec3 q = vec3( dot(p,vec2(127.1,311.7)), 
+                   dot(p,vec2(269.5,183.3)), 
+                   dot(p,vec2(419.2,371.9)) );
+    return fract(sin(q)*43758.5453);
+}
+
+float iqnoise( in vec2 x, float u, float v ) {
+    vec2 p = floor(x);
+    vec2 f = fract(x);
+        
+    float k = 1.0+63.0*pow(1.0-v,4.0);
+    
+    float va = 0.0;
+    float wt = 0.0;
+    for (int j=-2; j<=2; j++) {
+        for (int i=-2; i<=2; i++) {
+            vec2 g = vec2(float(i),float(j));
+            vec3 o = hash3(p + g)*vec3(u,u,1.0);
+            vec2 r = g - f + o.xy;
+            float d = dot(r,r);
+            float ww = pow( 1.0-smoothstep(0.0,1.414,sqrt(d)), k );
+            va += o.z*ww;
+            wt += ww;
+        }
+    }
+    
+    return va/wt;
+}
+
+void main() {
+    vec2 st = gl_FragCoord.xy/u_resolution.xy;
+    vec3 color = vec3(0.0);
+
+    float n = iqnoise( 30.0*st, abs(cos(u_time*.25)), 0.);
+
+    gl_FragColor = vec4(vec3(n),1.0);
+}

11/NOTES.md

@@ -16,8 +16,18 @@ https://en.wikipedia.org/wiki/Perlin_noise
 
 https://en.wikipedia.org/wiki/Colors_of_noise
 
-https://en.wikipedia.org/wiki/Value_noise
-
 https://en.wikipedia.org/wiki/Pink_noise
 
-https://en.wikipedia.org/wiki/Shot_noise
+https://en.wikipedia.org/wiki/Shot_noise
+
+# Value Noise
+https://en.wikipedia.org/wiki/Value_noise
+https://www.shadertoy.com/view/lsf3WH
+
+# Gradient Noise
+http://en.wikipedia.org/wiki/Gradient_noise
+https://www.shadertoy.com/view/XdXGW8
+
+# Simplex Noise
+http://en.wikipedia.org/wiki/Simplex_noise
+https://www.shadertoy.com/view/Msf3WH

14/NOTES.md

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+
+No tile images
+https://www.shadertoy.com/view/4tsGzf
+https://www.shadertoy.com/view/lt2GDd
+