2 // fg_time.hxx -- data structures and routines for managing time related stuff.
4 // Written by Curtis Olson, started August 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)
31 # error This library requires C++
46 #include <Include/fg_types.h>
47 #include <Flight/flight.h>
50 // Define a structure containing global time parameters
52 // the date/time in various forms
53 // Unix "calendar" time in seconds
56 // Break down of GMT time
62 // modified Julian date
65 // side real time at prime meridian
68 // local side real time
71 // the difference between the precise sidereal time algorithm
72 // result and the course result.
73 // course + diff has good accuracy for the short term
76 // An offset in seconds from the true time. Allows us to adjust
77 // the effective time of day.
80 // How much to change the value of warp each iteration. Allows us
81 // to make time progress faster than normal.
85 extern struct fgTIME cur_time_params;
88 typedef struct fg_timestamp_t {
94 // Portability wrap to get current time.
95 void timestamp(fg_timestamp *timestamp);
98 // Return duration in millis from first to last
99 long timediff(fg_timestamp *first, fg_timestamp *last);
102 // Return new timestamp given a time stamp and an interval to add in
103 void timesum(fg_timestamp *res, fg_timestamp *start, long millis);
106 // Update time variables such as gmt, julian date, and sidereal time
107 void fgTimeInit(struct fgTIME *t);
110 // Update the time dependent variables
111 void fgTimeUpdate(fgFLIGHT *f, struct fgTIME *t);
114 #endif // _FG_TIME_HXX
118 // Revision 1.2 1998/04/25 20:24:03 curt
119 // Cleaned up initialization sequence to eliminate interdependencies
120 // between sun position, lighting, and view position. This creates a
121 // valid single pass initialization path.
123 // Revision 1.1 1998/04/24 00:52:28 curt
124 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
126 // Separated out lighting calcs into their own file.
128 // Revision 1.20 1998/04/22 13:24:05 curt
129 // C++ - ifiing the code a bit.
130 // Starting to reorginize some of the lighting calcs to use a table lookup.
132 // Revision 1.19 1998/04/21 17:01:44 curt
133 // Fixed a problems where a pointer to a function was being passed around. In
134 // one place this functions arguments were defined as ( void ) while in another
135 // place they were defined as ( int ). The correct answer was ( int ).
137 // Prepairing for C++ integration.
139 // Revision 1.18 1998/04/08 23:35:40 curt
140 // Tweaks to Gnu automake/autoconf system.
142 // Revision 1.17 1998/04/03 22:12:56 curt
143 // Converting to Gnu autoconf system.
144 // Centralized time handling differences.
146 // Revision 1.16 1998/02/07 15:29:47 curt
147 // Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
148 // <chotchkiss@namg.us.anritsu.com>
150 // Revision 1.15 1998/01/27 00:48:06 curt
151 // Incorporated Paul Bleisch's <bleisch@chromatic.com> new debug message
152 // system and commandline/config file processing code.
154 // Revision 1.14 1998/01/22 02:59:43 curt
155 // Changed #ifdef FILE_H to #ifdef _FILE_H
157 // Revision 1.13 1998/01/19 19:27:20 curt
158 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
159 // This should simplify things tremendously.
161 // Revision 1.12 1998/01/05 18:44:37 curt
162 // Add an option to advance/decrease time from keyboard.
164 // Revision 1.11 1997/12/19 23:35:07 curt
165 // Lot's of tweaking with sky rendering and lighting.
167 // Revision 1.10 1997/12/15 23:55:07 curt
168 // Add xgl wrappers for debugging.
169 // Generate terrain normals on the fly.
171 // Revision 1.9 1997/12/10 22:37:55 curt
172 // Prepended "fg" on the name of all global structures that didn't have it yet.
173 // i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
175 // Revision 1.8 1997/12/09 04:25:38 curt
176 // Working on adding a global lighting params structure.
178 // Revision 1.7 1997/11/25 19:25:41 curt
179 // Changes to integrate Durk's moon/sun code updates + clean up.
181 // Revision 1.6 1997/09/20 03:34:35 curt
182 // Still trying to get those durned stars aligned properly.
184 // Revision 1.5 1997/09/16 15:50:31 curt
185 // Working on star alignment and time issues.
187 // Revision 1.4 1997/09/13 02:00:08 curt
188 // Mostly working on stars and generating sidereal time for accurate star
191 // Revision 1.3 1997/09/04 02:17:39 curt
194 // Revision 1.2 1997/08/27 03:30:36 curt
195 // Changed naming scheme of basic shared structures.
197 // Revision 1.1 1997/08/13 21:56:00 curt