/*
 *  Empire - A multi-player, client/server Internet based war game.
 *  Copyright (C) 1986-2000, Dave Pare, Jeff Bailey, Thomas Ruschak,
 *                           Ken Stevens, Steve McClure
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 *  ---
 *
 *  See the "LEGAL", "LICENSE", "CREDITS" and "README" files for all the
 *  related information and legal notices. It is expected that any future
 *  projects/authors will amend these files as needed.
 *
 *  ---
 *
 *  chance.c: return 1 if "roll" is under the chance.
 * 
 *  Known contributors to this file:
 *     
 */

#include "gen.h"

#ifdef hpux
void
srandom(unsigned int n)
{
	extern void srand48();

	srand48(n);
}

long
random(void)
{
	extern	long lrand48();

	return (lrand48());	/* 5/28/91 by bailey@mcs.kent.edu */
}
#endif

int
chance(double d)
{
	double	roll;

	roll = (random() & 0x7fff);

	if (d >  roll/32768.0)
		return 1;
	return 0;
}

int
roll(int n)
{
	return (random() % n) + 1;
}

/*
 * round value to nearest int (on the average). E.g. rounds up
 * with a chance proportional to the size of the fractional part.
 */
int
roundavg(double val)
{
	int	flr;

	flr = (int) val;
	if (val < 0)
		flr -= chance(flr - val);
	else
		flr += chance(val - flr);
	return flr;
}