theme mandelbrot

Assets/Scenes/GFLPC_Mandelbrot/MandelBrotHybrid.shader

@@ -7,10 +7,15 @@ Shader "Explorer/Mandelbrot"
         _Area("Area", vector) = (0, 0, 4 ,4)
         _Angle("Angle", range(-3.1415, 3.1415)) = 0
         _MaxIter("Max Iterations", range(0, 555)) = 255
-        _Color("Color", range(0,1)) = 0.5
-        _Repeat("Repeat", float) =  1
         _Speed("Speed", range(0, 1)) = 0.1
-        _Colors("Colors", vector) = (3.0, 4.0, 5.0, 0.0)
+        _EscapeRadius("EscapeRadius", range(2, 2000)) = 255
+
+        _SpectrumTexture("SpectrumTexture", 2D) = "white" {}
+        _SpectrumSize("SpectrumSize", float) = 16
+
+        _ThemeTexture("ThemeTexture", 2D) = "white" {}
+        _ThemeSize("ThemeSize", float) = 16
+
     }
     SubShader
     {
@@ -46,54 +51,68 @@ Shader "Explorer/Mandelbrot"
             }
 
             float4 _Area;
-            float _Angle;
-            float _Color;
-            float3  _Colors;
-            float _Repeat;
-            float _Speed;
             int _MaxIter;
+            float _EscapeRadius;
+            float _Speed;
+
+            sampler2D _SpectrumTexture;
+            int _SpectrumSize;
+
+            sampler2D _ThemeTexture;
+            int _ThemeSize;
+
             sampler2D _MainTex;
 
-            float2 rot(float2 p, float2 pivot, float a) {
-                float s = sin(a);
-                float c = cos(a);
-                p -= pivot;
-                p = float2(p.x*c-p.y*s, p.x*s+p.y*c);
-                p += pivot;
-
-                return p;
-            }
-
             fixed4 frag (v2f i) : SV_Target {
+                // drawing stuff
                 float2 uv = i.uv - 0.5;
                 float2 offset = _Area.xy + uv * _Area.zw;
-                float2 z;  // track pixel jumping across screen
-                float2 zPrev;
-                float r = 20;  // escape radius
+
+                // cool modulation
+                float sub = tex2D(_SpectrumTexture, 0.0);
+                float bass = tex2D(_SpectrumTexture, 0.25);
+                float mids = tex2D(_SpectrumTexture, 0.50);
+                float highs = tex2D(_SpectrumTexture, 0.75);
+
+                float r = lerp(2.0, 200, bass);
+                float maxIterations = lerp(2.0, 500, sub);
+
+                // fractal bits
                 float r2 = r*r;
+                float2 c = _Area.xy + uv * _Area.zw;
+                float2 z = 0;
+                float2 zNext;
+                int iter;
+                for (iter = 0; iter < maxIterations; iter ++)
+                {
+                    // f(z) = z^2 + c
+                    zNext.x = z.x * z.x - z.y * z.y   + c.x;
+                    zNext.y = 2 * z.x * z.y           + c.y;
+                    z = zNext;
 
-                float vxsquare = 0;
-                float vysquare = 0;
+                    // unbounded
+                    if (length(zNext) > r)
+                        break;
+                }
 
-                float iteration = 0;
-                float lastIteration = _MaxIter;
+                // in the set
+                // make it white
+                if (iter >= maxIterations) {
+                    return 0;
+                    return 1;
+                }
 
-                do {
-                    vxsquare = uv.x * uv.x;
-                    vysquare = uv.y * uv.y;
+                float val = iter / float(maxIterations);
+                float4 col = tex2D(_ThemeTexture, float2(sub, 1.0));
 
-                    uv = float2(vxsquare - vysquare, uv.x * uv.y * 2) + offset;
+                return col * val;
 
-                    iteration++;
-
-                    if ((lastIteration == _MaxIter) && (vxsquare + vysquare) > 4.0) {
-                        lastIteration = iteration + 1;
-                    }
-                } while (iteration < lastIteration);
-
-                float val = (float(iteration) - (log(log(sqrt(vxsquare + vysquare))) / log(2.0))) / float(_MaxIter);
-                return float4(sin(val * _Colors.x), sin(val * _Colors.y), sin(val * _Colors.z), 1);
+                // return float4(val, val, val, 1.0);
+                // return tex2D(_ThemeTexture, highs);
+                // float col = tex2D(_ThemeTexture, float2(highs * val, 1.0));
+                // return col;
 
+                // from spinny curvy brot
                 // float dist  = length(z); // distance from origin
                 // float fracIter  = (dist - r) / (r2 - r); // linear interpolation
                 // fracIter = log2(log(dist) / log(r) ); // double exponential interpolation

Assets/Scenes/GFLPC_Mandelbrot/Mandelbrot.shader

@@ -11,7 +11,7 @@ Shader "Explorer/Mandelbrot"
         _Repeat("Repeat", float) =  1
         _Speed("Speed", range(0, 1)) = 0.1
         _Symmetry("Symmetry", range(0, 1)) = 0
-        _EscapeRadius("EscapeRadius", range(0, 50)) = 20
+        _EscapeRadius("EscapeRadius", range(2, 200)) = 50
 
         _SpectrumTexture("SpectrumTexture", 2D) = "white" {}
         _SpectrumSize("SpectrumSize", float) = 16
@@ -80,17 +80,19 @@ Shader "Explorer/Mandelbrot"
                 c = rot(c, _Area.xy, _Angle);
                 float2 z;  // track pixel jumping across screen
                 float2 zPrev;
-                float r = lerp(2.0f, 20.0f, tex2D(_SpectrumTexture, 0.1f));
+                // float r = _EscapeRadius;
+                float r = lerp(2.0f, 50.0f, tex2D(_SpectrumTexture, 1.0f));
                 float r2 = r*r;
 
                 float iter;  // track current iteration
                 for (iter = 0; iter < _MaxIter; iter++) {
                     // update z based on previous z value and add original starting position
-                   //zPrev = z;
+                    // zPrev = z;
                     zPrev = rot(z, 0, _Time.y);
+                    // zPrev = rot(z, 0, clamp(tex2D(_SpectrumTexture, 0.1f) * 6.28, 1, 6.28));
+
                     z = float2(z.x*z.x-z.y*z.y, 2*z.x*z.y) + c;
                     if (dot(z, zPrev) > r2) {
-                    //if (length(z) > r) {
                         break;
                     }
                 }

Assets/Scenes/GFLPC_Mandelbrot/MandelbrotBW.shader

@@ -0,0 +1,98 @@
+Shader "Explorer/Mandelbrot"
+{
+    Properties
+    {
+        _MainTex ("Texture", 2D) = "white" {}
+        // first two numbers are center of area, second two - size of area
+        _Area("Area", vector) = (0, 0, 4 ,4)
+        _Angle("Angle", range(-3.1415, 3.1415)) = 0
+        _MaxIter("Max Iterations", range(0, 555)) = 255
+        // _Speed("Speed", range(0, 1)) = 0.1
+        _Colors("Colors", vector) = (0.5, 0.5, 0.5, 0.0)
+        _EscapeRadius("EscapeRadius", range(2, 2000)) = 255
+    }
+    SubShader
+    {
+        // No culling or depth
+        Cull Off ZWrite Off ZTest Always
+
+        Pass
+        {
+            CGPROGRAM
+            #pragma vertex vert
+            #pragma fragment frag
+
+            #include "UnityCG.cginc"
+
+            struct appdata
+            {
+                float4 vertex : POSITION;
+                float2 uv : TEXCOORD0;
+            };
+
+            struct v2f
+            {
+                float2 uv : TEXCOORD0;
+                float4 vertex : SV_POSITION;
+            };
+
+            v2f vert (appdata v)
+            {
+                v2f o;
+                o.vertex = UnityObjectToClipPos(v.vertex);
+                o.uv = v.uv;
+                return o;
+            }
+
+            float4 _Area;
+            float _Angle;
+            float3  _Colors;
+            // float _Speed;
+            int _MaxIter;
+            float _EscapeRadius;
+            sampler2D _MainTex;
+
+            fixed4 frag (v2f i) : SV_Target {
+                float2 uv = i.uv - 0.5;
+                float2 offset = _Area.xy + uv * _Area.zw;
+                float r = _EscapeRadius;
+                float r2 = r*r;
+
+                float2 c = _Area.xy + uv * _Area.zw;
+
+                float2 z = 0;
+                float2 zNext;
+                int iter;
+                for (iter = 0; iter < _MaxIter; iter ++)
+                {
+                    // f(z) = z^2 + c
+                    zNext.x = z.x * z.x - z.y * z.y   + c.x;
+                    zNext.y = 2 * z.x * z.y           + c.y;
+                    z = zNext;
+
+                    // Bounded?
+                    if (distance(z, float2(0,0)) > r)
+                        break;
+                }
+
+                float val = iter / float(_MaxIter);
+
+                return float4(val, val, val, 1);
+                return float4(sin(val), sin(val), sin(val), 1);
+
+                // float dist  = length(z); // distance from origin
+                // float fracIter  = (dist - r) / (r2 - r); // linear interpolation
+                // fracIter = log2(log(dist) / log(r) ); // double exponential interpolation
+                // iter -= fracIter;
+                // float m = sqrt(iter / _MaxIter);
+                // float4 col = sin(float4(.3, .45, .65, 1) * m * 20)*.5 + .5; // procedural colors
+                // col = tex2D(_MainTex, float2(m * _Repeat + _Time.y*_Speed, _Color));
+                // col *= smoothstep(3, 0, fracIter);
+                // float angle = atan2(z.x, z.y);
+                // col *= 1 + sin(angle*2 + _Time.y*4)*.2;
+                // return col;
+            }
+            ENDCG
+        }
+    }
+}

Assets/Scenes/GFLPC_Mandelbrot/MandelbrotBW.shader.meta

@@ -0,0 +1,10 @@
+fileFormatVersion: 2
+guid: ac37e4ae67210ed48bd3bb15fca8b2b2
+ShaderImporter:
+  externalObjects: {}
+  defaultTextures: []
+  nonModifiableTextures: []
+  preprocessorOverride: 0
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: