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// example6.c - Demonstrates how to miniz's PNG writer func
// Public domain, April 11 2012, Rich Geldreich, [email protected]. See "unlicense" statement at the end of tinfl.c.
// Mandlebrot set code from http://rosettacode.org/wiki/Mandelbrot_set#C
// Must link this example against libm on Linux.

// Purposely disable a whole bunch of stuff this low-level example doesn't use.
#define MINIZ_NO_STDIO
#define MINIZ_NO_TIME
#define MINIZ_NO_ZLIB_APIS
#include "miniz.h"

// Now include stdio.h because this test uses fopen(), etc. (but we still don't want miniz.c's stdio stuff, for testing).
#include <stdio.h>
#include <limits.h>
#include <math.h>

typedef unsigned char uint8;
typedef unsigned short uint16;
typedef unsigned int uint;

typedef struct
{
uint8 r, g, b;
} rgb_t;

static void hsv_to_rgb(int hue, int min, int max, rgb_t *p)
{
const int invert = 0;
const int saturation = 1;
const int color_rotate = 0;

if (min == max) max = min + 1;
if (invert) hue = max - (hue - min);
if (!saturation) {
p->r = p->g = p->b = 255 * (max - hue) / (max - min);
return;
}
double h = fmod(color_rotate + 1e-4 + 4.0 * (hue - min) / (max - min), 6);
double c = 255.0f * saturation;
double X = c * (1 - fabs(fmod(h, 2) - 1));

p->r = p->g = p->b = 0;

switch((int)h) {
case 0: p->r = c; p->g = X; return;
case 1: p->r = X; p->g = c; return;
case 2: p->g = c; p->b = X; return;
case 3: p->g = X; p->b = c; return;
case 4: p->r = X; p->b = c; return;
default:p->r = c; p->b = X;
}
}

int main(int argc, char *argv[])
{
(void)argc, (void)argv;

// Image resolution
const int iXmax = 4096;
const int iYmax = 4096;

// Output filename
static const char *pFilename = "mandelbrot.png";

int iX, iY;
const double CxMin = -2.5;
const double CxMax = 1.5;
const double CyMin = -2.0;
const double CyMax = 2.0;

double PixelWidth = (CxMax - CxMin) / iXmax;
double PixelHeight = (CyMax - CyMin) / iYmax;

// Z=Zx+Zy*i ; Z0 = 0
double Zx, Zy;
double Zx2, Zy2; // Zx2=Zx*Zx; Zy2=Zy*Zy

int Iteration;
const int IterationMax = 200;

// bail-out value , radius of circle
const double EscapeRadius = 2;
double ER2=EscapeRadius * EscapeRadius;

uint8 *pImage = (uint8 *)malloc(iXmax * 3 * iYmax);

// world ( double) coordinate = parameter plane
double Cx,Cy;

int MinIter = 9999, MaxIter = 0;

for(iY = 0; iY < iYmax; iY++)
{
Cy = CyMin + iY * PixelHeight;
if (fabs(Cy) < PixelHeight/2)
Cy = 0.0; // Main antenna

for(iX = 0; iX < iXmax; iX++)
{
uint8 *color = pImage + (iX * 3) + (iY * iXmax * 3);

Cx = CxMin + iX * PixelWidth;

// initial value of orbit = critical point Z= 0
Zx = 0.0;
Zy = 0.0;
Zx2 = Zx * Zx;
Zy2 = Zy * Zy;

for (Iteration=0;Iteration<IterationMax && ((Zx2+Zy2)<ER2);Iteration++)
{
Zy = 2 * Zx * Zy + Cy;
Zx =Zx2 - Zy2 + Cx;
Zx2 = Zx * Zx;
Zy2 = Zy * Zy;
};

color[0] = (uint8)Iteration;
color[1] = (uint8)Iteration >> 8;
color[2] = 0;

if (Iteration < MinIter)
MinIter = Iteration;
if (Iteration > MaxIter)
MaxIter = Iteration;
}
}

for(iY = 0; iY < iYmax; iY++)
{
for(iX = 0; iX < iXmax; iX++)
{
uint8 *color = (uint8 *)(pImage + (iX * 3) + (iY * iXmax * 3));

uint Iterations = color[0] | (color[1] << 8U);

hsv_to_rgb(Iterations, MinIter, MaxIter, (rgb_t *)color);
}
}

// Now write the PNG image.
{
size_t png_data_size = 0;
void *pPNG_data = tdefl_write_image_to_png_file_in_memory_ex(pImage, iXmax, iYmax, 3, &png_data_size, 6, MZ_FALSE);
if (!pPNG_data)
fprintf(stderr, "tdefl_write_image_to_png_file_in_memory_ex() failed!\n");
else
{
FILE *pFile = fopen(pFilename, "wb");
fwrite(pPNG_data, 1, png_data_size, pFile);
fclose(pFile);
printf("Wrote %s\n", pFilename);
}

// mz_free() is by default just an alias to free() internally, but if you've overridden miniz's allocation funcs you'll probably need to call mz_free().
mz_free(pPNG_data);
}

free(pImage);

return EXIT_SUCCESS;
}