1 // fg_time.hxx -- data structures and routines for managing time related stuff.
3 // Written by Curtis Olson, started August 1997.
5 // Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
29 # error This library requires C++
43 #include <simgear/compiler.h>
45 #ifdef FG_HAVE_STD_INCLUDES
51 #include <FDM/flight.hxx>
54 #include "lowleveltime.h"
56 // Define a structure containing global time parameters
60 // tzContainer stores all the current Timezone control points/
61 TimezoneContainer* tzContainer;
63 //Store the current local timezone name;
66 // Unix "calendar" time in seconds
69 // Break down of GMT time
75 // modified Julian date
78 double last_mjd, last_dy;
81 // side real time at prime meridian
84 // local sidereal time
87 // local offset to GMT
90 // the difference between the precise sidereal time algorithm
91 // result and the course result. course + diff has good accuracy
95 // An offset in seconds from the true time. Allows us to adjust
96 // the effective time of day.
99 // How much to change the value of warp each iteration. Allows us
100 // to make time progress faster than normal.
106 // Local magnetic variation and dip in radians
110 void local_update_sky_and_lighting_params( void );
117 inline double getJD() const { return jd; };
118 inline double getMjd() const { return mjd; };
119 inline double getLst() const { return lst; };
120 inline double getGst() const { return gst; };
121 inline time_t get_cur_time() const { return cur_time; };
122 inline struct tm* getGmt()const { return gmt; };
123 inline bool getPause() const { return pause; };
125 void adjust_warp(int val) { warp += val; };
126 void adjust_warp_delta(int val) { warp_delta += val; };
127 void togglePauseMode() { pause = !pause; };
129 // Initialize the time dependent variables
130 void init( double lon, double lat );
132 // Update the time dependent variables
133 void update( double lon, double lat, double alt_m );
136 void cal_mjd (int mn, double dy, int yr);
138 double sidereal_precise (double lng);
139 double sidereal_course(double lng);
140 static FGTime *cur_time_params;
142 // Some other stuff which were changed to FGTime members on
143 // questionable grounds -:)
144 // time_t get_start_gmt(int year);
145 time_t get_gmt(int year, int month, int day,
146 int hour, int minute, int second);
147 time_t get_gmt(struct tm* the_time);
149 char* format_time( const struct tm* p, char* buf );
150 long int fix_up_timezone( long int timezone_orig );
152 // Return magnetic variations
153 double getMagVar() const { return magvar; }
154 double getMagDip() const { return magdip; }
158 inline time_t FGTime::get_gmt(struct tm* the_time) // this is just a wrapper
160 //printf("Using: %24s as input\n", asctime(the_time));
161 return get_gmt(the_time->tm_year,
170 #endif // _FG_TIME_HXX