document distributed with 4.3BSD

[unix-history] / usr / src / lib / libcurses / PSD.doc / twinkle2.c

/*
* Copyright (c) 1980 Regents of the University of California.
* All rights reserved.  The Berkeley software License Agreement
* specifies the terms and conditions for redistribution.
*/

#ifndef lint
static char sccsid[] = "@(#)twinkle2.c  6.1 (Berkeley) %G%";
#endif not lint

extern int      _putchar();

main()
{
       reg char        *sp;

       srand(getpid());                /* initialize random sequence */

       if (isatty(0)) {
              gettmode();
              if ((sp = getenv("TERM")) != NULL)
                      setterm(sp);
               signal(SIGINT, die);
       }
       else {
               printf("Need a terminal on %d\n", _tty_ch);
               exit(1);
       }
       _puts(TI);
       _puts(VS);

       noecho();
       nonl();
       tputs(CL, NLINES, _putchar);
       for (;;) {
               makeboard();            /* make the board setup */
               puton('*');             /* put on '*'s */
               puton(' ');             /* cover up with ' 's */
       }
}

puton(ch)
char    ch;
{
       reg LOCS        *lp;
       reg int         r;
       reg LOCS        *end;
       LOCS            temp;
       static int      lasty, lastx;

       end = &Layout[Numstars];
       for (lp = Layout; lp < end; lp++) {
               r = rand() % Numstars;
               temp = *lp;
               *lp = Layout[r];
               Layout[r] = temp;
       }

       for (lp = Layout; lp < end; lp++)
                       /* prevent scrolling */
               if (!AM || (lp->y < NLINES - 1 || lp->x < NCOLS - 1)) {
                       mvcur(lasty, lastx, lp->y, lp->x);
                       putchar(ch);
                       lasty = lp->y;
                       if ((lastx = lp->x + 1) >= NCOLS)
                               if (AM) {
                                       lastx = 0;
                                       lasty++;
                               }
                               else
                                       lastx = NCOLS - 1;
               }
}