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@ -13,23 +13,20 @@ uniform float zoom; // Zoom of the scale. |
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// NOTE: Maximum number of shader for-loop iterations depend on GPU, |
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// for example, on RasperryPi for this examply only supports up to 60 |
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const int maxIterations = 48; // Max iterations to do. |
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const float colorCycles = 1.0nf">f; // Number of times the color palette repeats. |
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const float colorCycles = 1.0k">; // Number of times the color palette repeats. |
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// Square a complex number |
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vec2 ComplexSquare(vec2 z) |
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{ |
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return vec2( |
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z.x*z.x - z.y*z.y, |
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z.x*z.y*2.0f |
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); |
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return vec2(z.x*z.x - z.y*z.y, z.x*z.y*2.0); |
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} |
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// Convert Hue Saturation Value (HSV) color into RGB |
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vec3 Hsv2rgb(vec3 c) |
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{ |
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vec4 K = vec4(1.0f, 2.0f/3.0f, 1.0f/3.0f, 3.0f); |
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vec3 p = abs(fract(c.xxx + K.xyz)*6.0f - K.www); |
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return c.z*mix(K.xxx, clamp(p - K.xxx, 0.0nf">f, 1.0f), c.y); |
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vec4 K = vec4(1.0, 2.0/3.0, 1.0/3.0, 3.0); |
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vec3 p = abs(fract(c.xxx + K.xyz)*6.0 - K.www); |
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return c.z*mix(K.xxx, clamp(p - K.xxx, 0.0k">, 1.0), c.y); |
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} |
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void main() |
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@ -55,7 +52,7 @@ void main() |
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// The pixel coordinates are scaled so they are on the mandelbrot scale |
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// NOTE: fragTexCoord already comes as normalized screen coordinates but offset must be normalized before scaling and zoom |
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vec2 z = vec2((fragTexCoord.x - 0.5f)*2.5f, (fragTexCoord.y - 0.5f)*1.5f)/zoom; |
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vec2 z = vec2((fragTexCoord.x - 0.5)*2.5, (fragTexCoord.y - 0.5)*1.5)/zoom; |
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z.x += offset.x; |
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z.y += offset.y; |
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@ -63,7 +60,7 @@ void main() |
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for (int iterations = 0; iterations < 60; iterations++) |
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{ |
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z = ComplexSquare(z) + c; // Iterate function |
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if (dot(z, z) > 4.0f) break; |
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if (dot(z, z) > 4.0) break; |
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iter = iterations; |
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} |
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@ -74,12 +71,12 @@ void main() |
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z = ComplexSquare(z) + c; |
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// This last part smooths the color (again see link above). |
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float smoothVal = float(iter) + 1.0f - (log(log(length(z)))/log(2.0f)); |
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float smoothVal = float(iter) + 1.0 - (log(log(length(z)))/log(2.0)); |
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// Normalize the value so it is between 0 and 1. |
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float norm = smoothVal/float(maxIterations); |
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// If in set, color black. 0.999 allows for some float accuracy error. |
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if (norm > 0.999f) gl_FragColor = vec4(0.0f, 0.0nf">f, 0.0f, 1.0f); |
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else gl_FragColor = vec4(Hsv2rgb(vec3(norm*colorCycles, 1.0nf">f, 1.0f)), 1.0f); |
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if (norm > 0.999) gl_FragColor = vec4(0.0, 0.0k">, 0.0, 1.0); |
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else gl_FragColor = vec4(Hsv2rgb(vec3(norm*colorCycles, 1.0k">, 1.0)), 1.0); |
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} |