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/* Include libraries */
#include <SDL2/SDL.h>
/* Include header files */
#include "fractData.hh"
#include "genf.hh"
#include "mansdl.hh"
void genf::julia(SDL_Renderer* renderer, fractData* fd) {
constexpr double max = 2.25;
constexpr double min = -2.25;
for(unsigned int x = 0; x < fd->width; ++x)
for(unsigned int y = 0; y < fd->height; ++y) {
long double r = fd->julia_real;
long double i = fd->julia_imag;
long double r2 = x * ((max + fd->real * fd->zoom) / fd->zoom - (min + fd->real * fd->zoom) / fd->zoom) / fd->width + (min + fd->real * fd->zoom) / fd->zoom;
long double i2 = y * ((max + fd->imag * fd->zoom) / fd->zoom - (min + fd->imag * fd->zoom) / fd->zoom) / fd->width + (min + fd->imag * fd->zoom) / fd->zoom;
unsigned int iter;
for(iter = 0; iter < fd->maxIter; ++iter) {
if(r2 * r2 + i2 * i2 >= 4.0)
break;
long double r2Temp = r2 * r2 - i2 * i2 + r;
long double i2Temp = 2.0 * r2 * i2 + i;
if(r2 == r2Temp && i2 == i2Temp) {
iter = fd->maxIter;
break;
}
r2 = r2Temp;
i2 = i2Temp;
}
unsigned short int red = 0;
unsigned short int green = 0;
unsigned short int blue = 0;
if(iter != fd->maxIter) {
double t = (double)(iter) / (double)(fd->maxIter);
red = (int)(9.0 * (1.0 - t) * t * t * t * 255.0);
green = (int)(15.0 * (1.0 - t) * (1.0 - t) * t * t * 255.0);
blue = (int)(8.5 * (1.0 - t) * (1.0 - t) * (1.0 - t) * t * 255.0);
}
SDL_SetRenderDrawColor(renderer, red, green, blue, SDL_ALPHA_OPAQUE);
SDL_RenderDrawPoint(renderer, x, y);
}
}
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