61 lines
2.5 KiB
C
61 lines
2.5 KiB
C
#include "tricorn_V3.h"
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static const float convergenceLimit = 2.0f; // Mandelbrot set limit
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static unsigned converge(float complex position,unsigned n);
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/**
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* @brief Generates a Tricorn fractal image using the standard, unoptimized scalar implementation for benchmarking comparison (Version 2).
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* @param start The starting complex coordinate (bottom-left or top-left depending on height sign).
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* @param width The width of the target image in pixels.
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* @param height The height of the target image. A negative height reverses the Y-axis calculation.
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* @param res The step size (resolution) per pixel in the complex plane.
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* @param n The maximum number of mathematical iterations per pixel.
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* @param color If true, generates a 24-bit RGB image. If false, writes a grayscale image.
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* @param img Pointer to the pre-allocated memory buffer where the bitmap data will be stored.
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*/
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void tricorn_V3(float complex start, size_t width, ssize_t height, float res, unsigned n, _Bool color, unsigned char* img){
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float imag_direction = height < 0 ? -1.0f : 1.0f;
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unsigned bytesPerColor = color ? 3 : 1;
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height = height < 0? -height : height;
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// Simple iteration over every pixel in the picture
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for(size_t i = 0; i < width; i++){
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for(ssize_t j = 0; j < height; j++){
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unsigned value = converge(start + (i*res - I* imag_direction*j*res),n);
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// Pixel value position in the output array
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size_t position = (j*width +i) * bytesPerColor;
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if(!color){ // Grayscale colors as specified by the assignment r = g = b
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img[position] = value;
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}
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else{ // Temporary colors with random multipliers
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img[position] = ((value*3) % 255);
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img[position + 1] = ((value*2) % 255) ;
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img[position + 2] = ((value*5) % 255);
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}
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}
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}
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}
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// Iterative application of the equation given by the assignment
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static unsigned converge(float complex position,unsigned n){
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complex float result = 0;
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for(unsigned i = 0; i < n; i++){
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// Detection of unbounded behaviour
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// If the magnitude of the result vector is greater than the convergence limit, we know that the function will grow unbounded
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// Current convergence limit taken from mandelbrot set
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if(sqrtf(powf (crealf(result),2)+powf(cimagf(result),2)) > convergenceLimit)
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return 255-4*(i % 64);
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// Application of the given complex equation with m = 2
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result = cpowf(conjf(result),2) + position;
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}
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return 0;
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} |