Rat's Nest 1/ratsnest1.iso/prgmming/c/trigjul.cpp

C/C++ Source or Header | 1996-02-19 | 5.1 KB | 165 lines

//

//+-----------------------------------------------------------------+

//+ Program TRIGJUL.CPP                                             +

//+ Plots 10 Julia Set-like fractals from trigonometric functions.  +

//+ By F.A.A. Barbuto, February 6th 1994                            +

//+ E-Mail: [e-mail] (Rio de Janeiro, BRAZIL). +

//+ Needs SVGA256.H and SVGA256.BGI, supports up to five screens.   +

//+ Suggested starting colours: 33, 16, 40, 145.                    +

//+-----------------------------------------------------------------+

//

#include <stdio.h>

#include "svga256.h"

#include <conio.h>

#include <graphics.h>

#include <math.h>

#include <complex.h>



//void far initgraph(int far *,int far *,char far *);



int Vid; // Global variable //



int huge DetectVGA256()

{

  printf("\nWhich video mode would you like to use? \n\n");

  printf(" 0 - 320x200x256\n");

  printf(" 1 - 640x400x256\n");

  printf(" 2 - 640x480x256\n");

  printf(" 3 - 800x600x256\n");

  printf(" 4 - 1024x768x256\n\n>");

  scanf("%d",&Vid);

  if((Vid<0) || (Vid)>4) Vid = 2;

  return Vid;

}



void main()

{

      double Pi=3.1415926535897932, Inv_e=1.0/2.7182818284590452;

      double xmin=-Pi, xmax=Pi, ymin=-Pi, ymax=Pi, fact=1.0;

      double ypy, x, y, yp, p, q, r, deltap, deltaq;

      int istart, maxiter;

      register int npix, npiy, np, nq, npy, k, ipen;

      complex c, z, I=(0.0,1.0);

      int graphdriver=DETECT, graphmode, index;



      clrscr();

      printf("\n                  Select a formulation:   \n\n\n");

      printf(" 1: Pi*cos(z)     2: Pi*sin(z)      3: (1/e + 0.1)*exp(z)\n\n");

      printf(" 4: z*sin(z)      5: 2.96*cos(z)    6: sin(z)*cos(z)\n\n");

      printf(" 7: 2.945*cos(z)  8: 2.935*cos(z)   9: cosh(z)\n\n");

      printf("10: sinh(z)       Default: exp(z)*cos(z) (Arara)");

      printf("\n\n>");

      scanf("%d",&index);

      printf("\n  Number of iterations (maximum=default=16000)? \n\n>");

      scanf("%d",&maxiter);

      printf("\n  Set starting colour (>=0 , <=256)?");

      printf("\n  (suggested: 33, 16, 40, 145)\n\n>");

      scanf("%d",&istart);

      if((maxiter>500) || (maxiter)<=0) maxiter = 500;

      if((istart)<=0 || (istart>256)) istart = 0;

      clrscr();



      installuserdriver("Svga256",DetectVGA256);

      initgraph(&graphdriver, &graphmode, "C:\\BORLANDC\\BGI");



      if (Vid == 0) { npix = 320; npiy = 200;}

      if (Vid == 1) { npix = 640; npiy = 400;}

      if (Vid == 2) { npix = 640; npiy = 480;}

      if (Vid == 3) { npix = 800; npiy = 600;}

      if (Vid == 4) { npix =1024; npiy = 768;}

      if ((Vid>4) || (Vid<0)) { npix = 640; npiy = 480;}



      if(fact>=1.0 || fact <=0.0)

    fact = 1.0;

      else {

    npix = (int)(npix*fact);

    npiy = (int)(npiy*fact);

      }

      ypy = (double)npiy - 0.5;

      deltap = (xmax-xmin)/(npix-1);

      deltaq = (ymax-ymin)/(npiy-1);



      if(ymin==-ymax)

     npy = npiy/2;

      else

     npy = npiy;



     cleardevice();

     for (np=0; np<=npix-1; np++) {

       x = xmin + (double)np*deltap;

       for (nq=0; nq<=npy-1; nq++) {

     y = ymin + (double)nq*deltaq;

     k  = 0;

     p = 0.0;

     q = 0.0;

     c = complex(p,q);

     z = complex(x,y);

//

     do {

       if    (index == 1) z = Pi*cos(z) + c;

       else

          if (index == 2) z = Pi*sin(z) + c;

       else

          //Much better than "The Science of Fractal Images" Fig 3.9,

          //pg. 161, uh?

          if (index == 3) z = (Inv_e + 0.1)*exp(z) + c;

       else

          if (index == 4) z = z*sin(z) + c;

       else

          //See a zoom at "The Science of Fractal Images" pg. 119,

          //Plate 19.

          if (index == 5) z = 2.96*cos(z) + c;

       else

          //This is quite similar to the picture shown in "The Science

          //of Fractal Images", pg.162, Fig. 3.10a.

          if (index == 6) z = sin(z)*cos(z) + c;

       else

          //See a zoom at "The Science of Fractal Images" pg. 119,

          //Plate 20.

          if (index == 7) z = 2.945*cos(z) + c;

       else

          //See a zoom at "The Science of Fractal Images" pg. 119,

          //Plate 21.

          if (index == 8) z = 2.935*cos(z) + c;

       else

          if (index == 9) z = cosh(z) + c;

       else

          if (index ==10) z = sinh(z) + c;

       else

          //Default: Arara

          if ((index < 1) || (index > 10))  z = cos(z)*exp(z) + c;



       r = abs(z);

       k++;



       if (r >= maxiter) {

         ipen = istart + k;

         if (ymin == -ymax) {

           putpixel(np,nq,ipen);

           putpixel(np,npiy-nq-1,ipen);

         }

         else

           putpixel(np,nq,ipen);

       }



       if (k == maxiter) {

         ipen = 33;

         if (ymin == -ymax) {

           ypy = double(npiy) - nq - 0.5;

           putpixel(np,ypy,ipen);

           putpixel(np,nq,ipen);

         }

         else

           putpixel(np,nq,33);

       }



       p = real(z);

       q = imag(z);

     } while (r <= maxiter && k<=maxiter);

       }

       if(kbhit()) break;

     }

     getch();

     closegraph();

}