//+-------------------------------------------------------------------------+
//+ Order & Beauty from Chaos - Program FASTBALL.C                          +
//+                                                                         +
//+ By Ramiro Perez (Panama), rperez@ns.pa (Original program in Turbo       +
//+ BASIC) and Fausto A. A. Barbuto (Brazil), BJ06@C53000.PETROBRAS.ANRJ.BR +
//+ (Turbo BASIC to Borland C implementation).                              +
//+                                                                         +
//+ Plots thousands of randomly-generated spheres and rosettes, some very   +
//+ intriguing (rotating and pulsating).                                    +
//+ Random number function by Michael Sargent (USA), msargent@moose.uvm.edu +
//+ No SVGA drivers needed.                                                 +
//+                                                                         +
//+ INSTRUCTIONS: press 'n' or 'N' to see the next plot; any other key will +
//+ stop the execution.                                                     +
//+-------------------------------------------------------------------------+
#include <math.h>
#include <graphics.h>
#include <conio.h>
#include <stdlib.h>

double qsrandom(void);

void main(void)
{
  double ra, rnd1, in, in2, an, an2, x, y, c1, c2;
  int ipal1[6] = {1,9,25,11,31,63}, ipal2[6] = {4,36,52,38,54,62};
  int i, k, nx, ny, GraphDriver=DETECT, GraphMode;
  char key;

  initgraph(&GraphDriver,&GraphMode,"C:\\BORLANDC\\BGI");

  c1 = 640.0/3.1; c2 = 480.0/2.1;
  do {
    rnd1 = qsrandom();
    if (rnd1 >= 0.5) for (i=0;i<=5;i++) setpalette(i,ipal1[i]);
    else             for (i=0;i<=5;i++) setpalette(i,ipal2[i]);

    in  = 6.24*qsrandom(); in2 = 6.24*qsrandom();

    cleardevice();
    setbkcolor(BLACK);

    do {
      an = an + in; an2 = an2 + in2;
      ra = sin(an2);
      x = ra*sin(an); y = ra*cos(an);
      nx = c1*(x + 1.55); ny = c2*(y + 1.05);
      k = getpixel(nx,ny);
      if (k < 6) putpixel (nx,ny,(k+1));
    } while (!kbhit());
    key = getch();
  } while ((key == 'n') || (key == 'N'));
  closegraph();
}

double qsrandom(void)
{
   int random_integer, temp_integer;
   double random_double, temp_double;

   random_integer = random(RAND_MAX);
   random_double = (double)random_integer / RAND_MAX;
   temp_integer = random(30519);
   temp_double = (double)temp_integer / 1000000000L;
   random_double += temp_double;
   return(random_double);
}