/*
 * Bryan Ward
 * movie_julia.c - Generates the frames for a julia set movie
 */

#include <stdio.h>
#include <complex.h>
#include <math.h>
#include <float.h>
#include <stdlib.h>

#define width 1280
#define height 1024
#define iter 255
#define frames 100
#define xmin -2.0
#define xmax 2.0
#define ymin -2.0
#define ymax 2.0

int
main ()
{
        FILE *fl;
        int x, y, i,f;
        double xpix, ypix;
        double complex z;
        double complex c;
        int escape;
	char file[4];
	int *final = malloc(sizeof(int)*width*height);
	if(final == NULL)
	{
		printf("out of memory\n");
		exit(1);
	}
//        int final[width * height];
	for(f = 0;f < frames;f++)
	{
		sprintf(file,"frames/%04d",f);
		c = f*.001;
	        if ((fl = fopen (file, "w")) == NULL)
	                fprintf (stderr, "Cannot open %s\n", file);
	        fprintf (fl, "P2\n");
	        fprintf (fl, "#Copyright (C) 2007 Bryan Ward\n");
	        fprintf (fl, "%d\t%d\n", width, height);
	        fprintf (fl, "255\n");
	
	        ypix = (ymax - ymin) / height;
	        xpix = (xmax - xmin) / width;
		
		for (i = 0; i < width * height; i++)
		{
			z = xmin + (i%width * xpix) + (ymin + (i/height * ypix))* I;
			final[i] = checkPoint(z,c);
		}

	        for (i = 0; i < width * height; i++)
	                fprintf (fl, "%d\n", final[i]);

	        fclose (fl);
	}
        return 0;
}

int
checkPoint (double complex z, double complex c)
{
//        double complex c = .32 + .043*I;
        int j = 0;
        while (sqrt (creal (z) * creal (z) + cimag (z) * cimag (z)) < 2
               && j < iter)
        {
                z = z * z + c;
                j++;
        }
        return j;
}