mad fractal action

Assets/Scenes/GFLPC_GradientBrot/NtrJulia.shader

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+Shader "Kaiju/Julia"
+{
+    Properties
+    {
+        _MainTex ("Texture", 2D) = "white" {}
+        _MaxIterations("Max Iterations", range(0, 555)) = 255
+        _Pan("Pan", vector) = (0.5, 0.0, 0.0, 0.0)
+        _Zoom("Zoom", range(0, 4)) = 3
+        _Aspect("Aspect", range(0, 4)) = 1
+        _JuliaSeed("JuliaSeed", vector) = (0.39, -0.2, 0.0, 0.0)
+        _Colors("Colors", vector) = (3.0, 3.0, 3.0, 0.0)
+    }
+    SubShader
+    {
+        // No culling or depth
+        Cull Off ZWrite Off ZTest Always
+
+        Pass
+        {
+            CGPROGRAM
+            // #pragma enable_d3d11_debug_symbols
+            #pragma target 3.0
+            #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;
+            }
+
+            float   _MaxIterations;
+            float2  _Pan;
+            float   _Zoom;
+            float   _Aspect;
+            float2  _JuliaSeed;
+            float3  _Colors;
+
+            float ComputeValue(float2 v, float2 offset) {
+                float vxsquare = 0;
+                float vysquare = 0;
+
+                float iteration;
+                for (iteration = 0; iteration < _MaxIterations; iter++) {
+
+                }
+
+                // do {
+                //     vxsquare = v.x * v.x;
+                //     vysquare = v.y * v.y;
+
+                //     v = float2(vxsquare - vysquare, v.x * v.y * 2) + offset;
+
+                //     iteration++;
+
+                //     if ((lastIteration == _MaxIterations) && (vxsquare + vysquare) > 4.0) {
+                //         lastIteration = iteration + 1;
+                //     }
+                // } while (iteration < lastIteration);
+
+                // return (float(iteration) - (log(log(sqrt(vxsquare + vysquare))) / log(2.0))) / float(_MaxIterations);
+            }
+
+//         for each pixel (Px, Py) on the screen do
+    // x0 := scaled x coordinate of pixel (scaled to lie in the Mandelbrot X scale (-2.5, 1))
+    // y0 := scaled y coordinate of pixel (scaled to lie in the Mandelbrot Y scale (-1, 1))
+    // x := 0.0
+    // y := 0.0
+    // iteration := 0
+    // max_iteration := 1000
+    // // Here N = 2^8 is chosen as a reasonable bailout radius.
+
+    // while x*x + y*y ≤ (1 << 16) and iteration < max_iteration do
+    //     xtemp := x*x - y*y + x0
+    //     y := 2*x*y + y0
+    //     x := xtemp
+    //     iteration := iteration + 1
+
+    // // Used to avoid floating point issues with points inside the set.
+    // if iteration < max_iteration then
+    //     // sqrt of inner term removed using log simplification rules.
+    //     log_zn := log(x*x + y*y) / 2
+    //     nu := log(log_zn / log(2)) / log(2)
+    //     // Rearranging the potential function.
+    //     // Dividing log_zn by log(2) instead of log(N = 1<<8)
+    //     // because we want the entire palette to range from the
+    //     // center to radius 2, NOT our bailout radius.
+    //     iteration := iteration + 1 - nu
+
+    // color1 := palette[floor(iteration)]
+    // color2 := palette[floor(iteration) + 1]
+    // // iteration % 1 = fractional part of iteration.
+    // color := linear_interpolate(color1, color2, iteration % 1)
+    // plot(Px, Py, color)
+
+            float4 Mandelbrot_PixelShader(float2 texCoord : TEXCOORD0) : COLOR0 {
+                float2 v = (texCoord - 0.5) * _Zoom * float2(1, _Aspect) - _Pan;
+                float val = ComputeValue(v, v);
+                return float4(sin(val * _Colors.x), sin(val * _Colors.y), sin(val * _Colors.z), 1);
+            }
+
+            float4 Julia_PixelShader(float2 texCoord : TEXCOORD0) : COLOR0 {
+                _JuliaSeed = float2(sin(_Time.y), cos(_Time.y));
+                float2 v = (texCoord - 0.5) * _Zoom * float2(1, _Aspect) - _Pan;
+                float val = ComputeValue(v, _JuliaSeed);
+                return float4(sin(val * _Colors.x), sin(val * _Colors.y), sin(val * _Colors.z), 1);
+            }
+
+            float4 frag (v2f i) : SV_Target {
+                // return Julia_PixelShader(i.uv);
+                return Mandelbrot_PixelShader(i.uv);
+            }
+
+            ENDCG
+        }
+    }
+}