/***********************************************
*	Juliazoom2.c
*
*  Generates a RAW format file of an image 
*  of a Julia set (grayscale)
*
*  C source file by Alberto Strumia
*
************************************************/


#include<stdio.h>
/* definition of constants */

#define Radius 10
#define Cx -0.27334
#define Cy -0.00642
#define Side 1.2
#define M 700
#define Num 1024
/* alternative values x0 = 0 Side 0.12 Num = 1024, x0 = -1.2 y0 = 1.2 Side = 0.08, Num = 1048 */

/* main program */
main()
{
	
	int p, q, n, w;
	double x, y, xx, yy, Incx, Incy;

	FILE *fp;
	fp = fopen("Julia.raw","w");

	for (p = 1; p <= M; p++)
	{
		Incy = - Side + 2*Side/M*p;
	
			printf("%i %%\n", p*100/M);
		
		for (q = 1; q <= M; q++)
		{
			Incx = - Side + 2*Side/M*q;
			
		x =  Incx;
		y =  Incy;
		w = 200;
		
			
			for ( n = 1; n <= Num; ++n)
			{
				xx = x*x - y*y - Cx;
				yy = 2*x*y - Cy;
				
				x = xx;
				y = yy;
				
				if ( x*x + y*y > Radius )
					{
						w = n;
						n = Num;
					}
			}
		fprintf(fp, "%c", w/4 );
		}
	}
	
	fclose(fp);
}

 /* end of main program */