/*
Bryan Ward
buddha.c - buddhabrot generation program
*/

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

#define width 1280
#define height 1024
#define iter 1000
#define iteration (10000000L)
#define xmin -2.0
#define xmax 2.0
#define ymin -2.0
#define ymax 2.0

#define max(x,y) (x > y ? x : y)
#define min(x,y) (x < y ? x : y)

int checkPoint(double complex c, int *n, double complex *seq)
{
	int k;
	double complex z = 0;
	double complex new;
	*n = 0;
	for(k = 0;k < iter;k++)
	{
		z = z*z + c;
		seq[k] = z;
		if(creal(z)*creal(z) + cimag(z) *cimag(z) > 10)
		{
			*n = k;
			return 1;
		}
	}
	return 0;
}
int main(int argc, char ** argv)
{
	FILE* fl;
	int i,n,ix,iy,t;
	double complex c;
	unsigned int *image = NULL;
	double complex *seq = NULL;
	int max,min,range;
	
	if((image = (unsigned int*)malloc(width*height*sizeof(unsigned int))) == NULL)
	{
		fprintf(stderr,"Failed to malloc memory for the image\n");
	}
	if((seq = (double complex*)malloc(iter*sizeof(unsigned int))) == NULL)
	{
		fprintf(stderr,"Failed to malloc memory for the sequence\n");
	}

	for(i = 0; i < width*height;i++)
	{
		image[i] = 0;
	}
	for(t = 0;t < iteration;t++)
	{
		c = 6*drand48() - 3 + (6*drand48()-3)*I;
		if(checkPoint(c,&n,seq))
		{
			for(i = 0; i < n;i++)
			{
				ix = .3 * width * (creal(seq[i]) + .5) + width/2;
				iy = .3 * height * cimag(seq[i]) + height/2;
				if(ix >=0 && iy >= 0 && ix < width && iy < height)
					image[iy*width+ix]++;
			}
		}
	}
	if((fl=fopen("image_buddha.pgm","w"))==NULL)
	{
		fprintf(stderr,"Failed to open the image file");
	}
	fprintf(fl,"P5\n#Copyright (C) 2007 Bryan Ward\n%d\t%d\n255\n",width,height);

	max = image[0];
	min = image[0];
	for(i = 0; i < width*height;i++)
	{
		max = max(max,image[i]);
		min = min(min,image[i]);
	}
	printf("Max: %d\tMin: %d\n",max,min);
	range = max - min;
	for(i = 0; i < width*height;i++)
	{
		fprintf(fl,"%c",(unsigned char)(255*(image[i]-min)/range));
	}
	free(seq);
	free(image);
	close(fl);
	return 0;
}