71 lines
1.8 KiB
C
71 lines
1.8 KiB
C
// fg_random.c -- routines to handle random number generation
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//
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// Written by Curtis Olson, started July 1997.
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//
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// Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
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//
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// This program is free software; you can redistribute it and/or
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// modify it under the terms of the GNU General Public License as
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// published by the Free Software Foundation; either version 2 of the
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// License, or (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful, but
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// WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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// General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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//
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// $Id$
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#ifdef HAVE_CONFIG_H
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# include <config.h>
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#endif
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#include <stdio.h>
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#include <stdlib.h> // for random(), srandom()
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#include <time.h> // for time() to seed srandom()
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#include "fg_random.h"
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#ifndef HAVE_RAND
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# ifdef sgi
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# undef RAND_MAX
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# define RAND_MAX 2147483647
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# endif
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#endif
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#ifdef __SUNPRO_CC
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extern "C" {
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long int random(void);
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void srandom(unsigned int seed);
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}
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#endif
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// Seed the random number generater with time() so we don't see the
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// same sequence every time
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void fg_srandom(void) {
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// fgPrintf( FG_MATH, FG_INFO, "Seeding random number generater\n");
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#ifdef HAVE_RAND
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srand(time(NULL));
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#else
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srandom(time(NULL));
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#endif
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}
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// return a random number between [0.0, 1.0)
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double fg_random(void) {
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#ifdef HAVE_RAND
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return(rand() / (double)RAND_MAX);
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#else
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return(random() / (double)RAND_MAX);
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#endif
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}
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