www.pudn.com > CG2Programs.rar > mandelbrot.c

/*  mandelbrot, Chapter 10, p. 384  */

#include 
#include 

/* EXAMPLE STARTS HERE */
#include "graphics.h"

typedef struct { float x, y; } Complex;

Complex complexSquare (Complex c)
{
  Complex cSq;

  cSq.x = c.x * c.x - c.y * c.y;
  cSq.y = 2 * c.x * c.y;
  return (cSq);
}

int iterate (Complex zInit, int maxIter)
{
  Complex z = zInit;
  int cnt = 0;

  /*  Quit when z * z > 4  */
  while ((z.x * z.x + z.y * z.y <= 4.0) && (cnt < maxIter)) {
    z = complexSquare (z);
    z.x += zInit.x;
    z.y += zInit.y;
    cnt++;
  }
  return (cnt);
}

void mandelbrot (int nx, int ny, int maxIter, float realMin,
		 float realMax, float imagMin, float imagMax)
{
  float realInc = (realMax - realMin) / nx;
  float imagInc = (imagMax - imagMin) / ny;
  Complex z;
  int x, y;
  int cnt;

  for (x=0, z.x=realMin; x