1 /**************************************************************************
2 * fg_timer.c -- time handling routines
4 * Written by Curtis Olson, started June 1997.
6 * Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of the
11 * License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 * (Log is kept at end of this file)
24 **************************************************************************/
27 #include <signal.h> /* for timer routines */
28 #include <stdio.h> /* for printf() */
31 # include <sys/timeb.h> /* for ftime() and struct timeb */
32 #elif defined(__MWERKS__)
33 # include <windows.h> /* For Metrowerks environment */
34 # include <winbase.h> /* There is no ANSI/MSL time function that */
35 /* contains milliseconds */
37 # include <sys/time.h> /* for get/setitimer, gettimeofday, struct timeval */
38 #endif /* USE_FTIME */
40 #include <Time/fg_timer.h>
43 unsigned long int fgSimTime;
46 static struct itimerval t, ot;
47 static void (*callbackfunc)(int multi_loop);
50 /* This routine catches the SIGALRM */
51 void fgTimerCatch( void ) {
52 /* ignore any SIGALRM's until we come back from our EOM iteration */
53 signal(SIGALRM, SIG_IGN);
55 /* printf("In fgTimerCatch()\n"); */
57 /* -1 tells the routine to use default interval rather than something
58 dynamically calculated based on frame rate */
61 signal(SIGALRM, fgTimerCatch);
65 /* this routine initializes the interval timer to generate a SIGALRM after
66 * the specified interval (dt) */
67 void fgTimerInit(float dt, void (*f)()) {
75 usec = 1000000* (dt - (float) isec);
77 t.it_interval.tv_sec = isec;
78 t.it_interval.tv_usec = usec;
79 t.it_value.tv_sec = isec;
80 t.it_value.tv_usec = usec;
81 /* printf("fgTimerInit() called\n"); */
82 fgTimerCatch(); /* set up for SIGALRM signal catch */
83 terr = setitimer( ITIMER_REAL, &t, &ot );
85 printf("Error returned from setitimer");
89 #endif /* HAVE_ITIMER */
92 /* This function returns the number of milleseconds since the last
93 time it was called. */
94 int fgGetTimeInterval( void ) {
96 static int inited = 0;
99 static struct timeb last;
100 static struct timeb current;
101 #elif defined (__MWERKS__)
105 static struct timeval last;
106 static struct timeval current;
107 static struct timezone tz;
108 #endif /* USE_FTIME */
115 #elif defined (__MWERKS__)
118 gettimeofday(&last, &tz);
119 #endif /* USE_FTIME */
126 interval = 1000 * (current.time - last.time) +
127 (current.millitm - last.millitm);
128 #elif defined (__MWERKS__)
129 GetLocalTime(¤t);
130 interval = 1000 * (current.wSecond - last.wSecond) +
131 (current.wMilliseconds - last.wMilliseconds);
133 gettimeofday(¤t, &tz);
134 interval = 1000000 * (current.tv_sec - last.tv_sec) +
135 (current.tv_usec - last.tv_usec);
136 interval /= 1000; /* convert back to milleseconds */
137 #endif /* USE_FTIME */
147 /* Revision 1.10 1998/01/31 00:43:45 curt
148 /* Added MetroWorks patches from Carmen Volpe.
150 * Revision 1.9 1998/01/19 19:27:21 curt
151 * Merged in make system changes from Bob Kuehne <rpk@sgi.com>
152 * This should simplify things tremendously.
154 * Revision 1.8 1998/01/19 18:40:39 curt
155 * Tons of little changes to clean up the code and to remove fatal errors
156 * when building with the c++ compiler.
158 * Revision 1.7 1997/12/30 13:06:58 curt
159 * A couple lighting tweaks ...
161 * Revision 1.6 1997/07/12 02:13:04 curt
162 * Add ftime() support for those that don't have gettimeofday()
164 * Revision 1.5 1997/06/26 19:08:38 curt
165 * Restructuring make, adding automatic "make dep" support.
167 * Revision 1.4 1997/06/25 15:39:49 curt
168 * Minor changes to compile with rsxnt/win32.
170 * Revision 1.3 1997/06/17 16:52:04 curt
171 * Timer interval stuff now uses gettimeofday() instead of ftime()
173 * Revision 1.2 1997/06/17 03:41:10 curt
174 * Nonsignal based interval timing is now working.
175 * This would be a good time to look at cleaning up the code structure a bit.
177 * Revision 1.1 1997/06/16 19:24:20 curt