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clean ups ...

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This commit is contained in:
curt 2000-07-07 19:51:42 +00:00
parent d48b3f1e9a
commit cb29dcc238
2 changed files with 226 additions and 244 deletions
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358
simgear/timing/sg_time.cxx
View File

@ -64,14 +64,6 @@
SGTime::SGTime( const string& root )
{
/* if (cur_time_params) {
FG_LOG( FG_GENERAL, FG_ALERT,
"Error: only one instance of SGTime allowed" );
exit(-1);
} */
// cur_time_params = this;
FGPath zone( root );
zone.append( "Timezone" );
zone.append( "zone.tab" );
@ -92,30 +84,9 @@ SGTime::~SGTime()
}
}
void SGTime::updateLocal( double lon, double lat, const string& root )
{
time_t currGMT;
time_t aircraftLocalTime;
GeoCoord location( RAD_TO_DEG * lat, RAD_TO_DEG * lon );
GeoCoord* nearestTz = tzContainer->getNearest(location);
FGPath zone( root );
zone.append ("Timezone" );
zone.append ( nearestTz->getDescription() );
if ( zonename ) {
delete zonename;
}
zonename = strdup( zone.c_str() );
currGMT = get_gmt( gmtime(&cur_time) );
aircraftLocalTime = get_gmt( (fgLocaltime(&cur_time, zone.c_str())) );
local_offset = aircraftLocalTime - currGMT;
// cout << "Using " << local_offset << " as local time offset Timezone is "
// << zonename << endl;
}
// Initialize the time dependent variables (maybe I'll put this in the
// constructor later)
// Initialize the time related variables
void SGTime::init( double lon, double lat, const string& root )
// time_t timeOffset, sgTimingOffsetType offsetType )
{
FG_LOG( FG_EVENT, FG_INFO, "Initializing Time" );
gst_diff = -9999.0;
@ -158,15 +129,163 @@ void SGTime::init( double lon, double lat, const string& root )
}
// Update the time related variables
void SGTime::update( double lon, double lat, double alt_m, long int warp ) {
double gst_precise, gst_course;
FG_LOG( FG_EVENT, FG_DEBUG, "Updating time" );
// get current Unix calendar time (in seconds)
// warp += warp_delta;
cur_time = time(NULL) + warp;
FG_LOG( FG_EVENT, FG_DEBUG,
" Current Unix calendar time = " << cur_time
<< " warp = " << warp );
// get GMT break down for current time
gmt = gmtime(&cur_time);
FG_LOG( FG_EVENT, FG_DEBUG,
" Current GMT = " << gmt->tm_mon+1 << "/"
<< gmt->tm_mday << "/" << gmt->tm_year << " "
<< gmt->tm_hour << ":" << gmt->tm_min << ":"
<< gmt->tm_sec );
// calculate modified Julian date
// t->mjd = cal_mjd ((int)(t->gmt->tm_mon+1), (double)t->gmt->tm_mday,
// (int)(t->gmt->tm_year + 1900));
mjd = sgTimeCalcMJD( (int)(gmt->tm_mon+1), (double)gmt->tm_mday,
(int)(gmt->tm_year + 1900) );
// add in partial day
mjd += (gmt->tm_hour / 24.0) + (gmt->tm_min / (24.0 * 60.0)) +
(gmt->tm_sec / (24.0 * 60.0 * 60.0));
// convert "back" to Julian date + partial day (as a fraction of one)
jd = mjd + MJD0;
FG_LOG( FG_EVENT, FG_DEBUG, " Current Julian Date = " << jd );
// printf(" Current Longitude = %.3f\n", FG_Longitude * RAD_TO_DEG);
// Calculate local side real time
if ( gst_diff < -100.0 ) {
// first time through do the expensive calculation & cheap
// calculation to get the difference.
FG_LOG( FG_EVENT, FG_INFO, " First time, doing precise gst" );
gst_precise = gst = sidereal_precise(0.00);
gst_course = sidereal_course(0.00);
gst_diff = gst_precise - gst_course;
lst = sidereal_course(-(lon * RAD_TO_DEG)) + gst_diff;
} else {
// course + difference should drift off very slowly
gst = sidereal_course( 0.00 ) + gst_diff;
lst = sidereal_course( -(lon * RAD_TO_DEG)) + gst_diff;
}
FG_LOG( FG_EVENT, FG_DEBUG,
" Current lon=0.00 Sidereal Time = " << gst );
FG_LOG( FG_EVENT, FG_DEBUG,
" Current LOCAL Sidereal Time = " << lst << " ("
<< sidereal_precise(-(lon * RAD_TO_DEG))
<< ") (diff = " << gst_diff << ")" );
}
// Given lon/lat, update timezone information and local_offset
void SGTime::updateLocal( double lon, double lat, const string& root )
{
time_t currGMT;
time_t aircraftLocalTime;
GeoCoord location( RAD_TO_DEG * lat, RAD_TO_DEG * lon );
GeoCoord* nearestTz = tzContainer->getNearest(location);
FGPath zone( root );
zone.append ("Timezone" );
zone.append ( nearestTz->getDescription() );
if ( zonename ) {
delete zonename;
}
zonename = strdup( zone.c_str() );
currGMT = get_gmt( gmtime(&cur_time) );
aircraftLocalTime = get_gmt( (fgLocaltime(&cur_time, zone.c_str())) );
local_offset = aircraftLocalTime - currGMT;
// cout << "Using " << local_offset << " as local time offset Timezone is "
// << zonename << endl;
}
// given Julian Date and Longitude (decimal degrees West) compute
// Local Sidereal Time, in decimal hours.
//
// Provided courtesy of ecdowney@noao.edu (Elwood Downey)
double SGTime::sidereal_precise( double lng )
{
double lstTmp;
/* printf ("Current Lst on JD %13.5f at %8.4f degrees West: ",
mjd + MJD0, lng); */
// convert to required internal units
lng *= DEG_TO_RAD;
// compute LST and print
gst = sgTimeCalcGST( mjd );
lstTmp = gst - RADHR (lng);
lstTmp -= 24.0*floor(lstTmp/24.0);
// printf ("%7.4f\n", lstTmp);
// that's all
return (lstTmp);
}
// return a courser but cheaper estimate of sidereal time
double SGTime::sidereal_course( double lng )
{
time_t start_gmt, now;
double diff, part, days, hours, lstTmp;
char tbuf[64];
now = cur_time;
start_gmt = get_gmt(gmt->tm_year, 2, 21, 12, 0, 0);
FG_LOG( FG_EVENT, FG_DEBUG, " COURSE: GMT = "
<< sgTimeFormatTime(gmt, tbuf) );
FG_LOG( FG_EVENT, FG_DEBUG, " March 21 noon (GMT) = " << start_gmt );
diff = (now - start_gmt) / (3600.0 * 24.0);
FG_LOG( FG_EVENT, FG_DEBUG,
" Time since 3/21/" << gmt->tm_year << " GMT = " << diff );
part = fmod(diff, 1.0);
days = diff - part;
hours = gmt->tm_hour + gmt->tm_min/60.0 + gmt->tm_sec/3600.0;
lstTmp = (days - lng)/15.0 + hours - 12;
while ( lstTmp < 0.0 ) {
lstTmp += 24.0;
}
FG_LOG( FG_EVENT, FG_DEBUG,
" days = " << days << " hours = " << hours << " lon = "
<< lng << " lst = " << lstTmp );
return(lstTmp);
}
// given a date in months, mn, days, dy, years, yr, return the
// modified Julian date (number of days elapsed since 1900 jan 0.5),
// mjd. Adapted from Xephem.
double sgTimeCalcMJD(int mn, double dy, int yr) {
double mjd;
// internal book keeping data
static double last_mjd, last_dy;
static int last_mn, last_yr;
void SGTime::cal_mjd (int mn, double dy, int yr)
{
//static double last_mjd, last_dy;
//double mjd;
//static int last_mn, last_yr;
int b, d, m, y;
long c;
@ -203,12 +322,15 @@ void SGTime::cal_mjd (int mn, double dy, int yr)
last_dy = dy;
last_yr = yr;
last_mjd = mjd;
return mjd;
}
// given an mjd, calculate greenwich mean sidereal time, gst
void SGTime::utc_gst ()
{
double sgTimeCalcGST( double mjd ) {
double gst;
double day = floor(mjd-0.5)+0.5;
double hr = (mjd-day)*24.0;
double T, x;
@ -219,136 +341,29 @@ void SGTime::utc_gst ()
gst = (1.0/SIDRATE)*hr + x;
FG_LOG( FG_EVENT, FG_DEBUG, " gst => " << gst );
return gst;
}
// given Julian Date and Longitude (decimal degrees West) compute
// Local Sidereal Time, in decimal hours.
//
// Provided courtesy of ecdowney@noao.edu (Elwood Downey)
#if defined( HAVE_TIMEGM )
// ignore this function
#elif defined( MK_TIME_IS_GMT )
// ignore this function
#else // ! defined ( MK_TIME_IS_GMT )
double SGTime::sidereal_precise (double lng)
{
double lstTmp;
/* printf ("Current Lst on JD %13.5f at %8.4f degrees West: ",
mjd + MJD0, lng); */
// convert to required internal units
lng *= DEG_TO_RAD;
// compute LST and print
utc_gst();
lstTmp = gst - RADHR (lng);
lstTmp -= 24.0*floor(lstTmp/24.0);
// printf ("%7.4f\n", lstTmp);
// that's all
return (lstTmp);
}
// return a courser but cheaper estimate of sidereal time
double SGTime::sidereal_course(double lng)
{
//struct tm *gmt;
//double lstTmp;
time_t start_gmt, now;
double diff, part, days, hours, lstTmp;
char tbuf[64];
//gmt = t->gmt;
//now = t->cur_time;
now = cur_time;
start_gmt = get_gmt(gmt->tm_year, 2, 21, 12, 0, 0);
FG_LOG( FG_EVENT, FG_DEBUG, " COURSE: GMT = " << format_time(gmt, tbuf) );
FG_LOG( FG_EVENT, FG_DEBUG, " March 21 noon (GMT) = " << start_gmt );
diff = (now - start_gmt) / (3600.0 * 24.0);
FG_LOG( FG_EVENT, FG_DEBUG,
" Time since 3/21/" << gmt->tm_year << " GMT = " << diff );
part = fmod(diff, 1.0);
days = diff - part;
hours = gmt->tm_hour + gmt->tm_min/60.0 + gmt->tm_sec/3600.0;
lstTmp = (days - lng)/15.0 + hours - 12;
while ( lstTmp < 0.0 ) {
lstTmp += 24.0;
// Fix up timezone if using ftime()
static long int fix_up_timezone( long int timezone_orig ) {
# if !defined( HAVE_GETTIMEOFDAY ) && defined( HAVE_FTIME )
// ftime() needs a little extra help finding the current timezone
struct timeb current;
ftime(&current);
return( current.timezone * 60 );
# else
return( timezone_orig );
# endif
}
FG_LOG( FG_EVENT, FG_DEBUG,
" days = " << days << " hours = " << hours << " lon = "
<< lng << " lst = " << lstTmp );
return(lstTmp);
}
// Update time variables such as gmt, julian date, and sidereal time
void SGTime::update( double lon, double lat, double alt_m, long int warp ) {
double gst_precise, gst_course;
FG_LOG( FG_EVENT, FG_DEBUG, "Updating time" );
// get current Unix calendar time (in seconds)
// warp += warp_delta;
cur_time = time(NULL) + warp;
FG_LOG( FG_EVENT, FG_DEBUG,
" Current Unix calendar time = " << cur_time
<< " warp = " << warp );
// get GMT break down for current time
gmt = gmtime(&cur_time);
FG_LOG( FG_EVENT, FG_DEBUG,
" Current GMT = " << gmt->tm_mon+1 << "/"
<< gmt->tm_mday << "/" << gmt->tm_year << " "
<< gmt->tm_hour << ":" << gmt->tm_min << ":"
<< gmt->tm_sec );
// calculate modified Julian date
// t->mjd = cal_mjd ((int)(t->gmt->tm_mon+1), (double)t->gmt->tm_mday,
// (int)(t->gmt->tm_year + 1900));
cal_mjd ((int)(gmt->tm_mon+1), (double)gmt->tm_mday,
(int)(gmt->tm_year + 1900));
// add in partial day
mjd += (gmt->tm_hour / 24.0) + (gmt->tm_min / (24.0 * 60.0)) +
(gmt->tm_sec / (24.0 * 60.0 * 60.0));
// convert "back" to Julian date + partial day (as a fraction of one)
jd = mjd + MJD0;
FG_LOG( FG_EVENT, FG_DEBUG, " Current Julian Date = " << jd );
// printf(" Current Longitude = %.3f\n", FG_Longitude * RAD_TO_DEG);
// Calculate local side real time
if ( gst_diff < -100.0 ) {
// first time through do the expensive calculation & cheap
// calculation to get the difference.
FG_LOG( FG_EVENT, FG_INFO, " First time, doing precise gst" );
gst_precise = gst = sidereal_precise(0.00);
gst_course = sidereal_course(0.00);
gst_diff = gst_precise - gst_course;
lst = sidereal_course(-(lon * RAD_TO_DEG)) + gst_diff;
} else {
// course + difference should drift off very slowly
gst = sidereal_course( 0.00 ) + gst_diff;
lst = sidereal_course( -(lon * RAD_TO_DEG)) + gst_diff;
}
FG_LOG( FG_EVENT, FG_DEBUG,
" Current lon=0.00 Sidereal Time = " << gst );
FG_LOG( FG_EVENT, FG_DEBUG,
" Current LOCAL Sidereal Time = " << lst << " ("
<< sidereal_precise(-(lon * RAD_TO_DEG))
<< ") (diff = " << gst_diff << ")" );
}
#endif
/******************************************************************
@ -452,27 +467,12 @@ time_t SGTime::get_gmt(int year, int month, int day, int hour, int min, int sec)
#endif // ! defined ( MK_TIME_IS_GMT )
}
// Fix up timezone if using ftime()
long int SGTime::fix_up_timezone( long int timezone_orig )
{
#if !defined( HAVE_GETTIMEOFDAY ) && defined( HAVE_FTIME )
// ftime() needs a little extra help finding the current timezone
struct timeb current;
ftime(&current);
return( current.timezone * 60 );
#else
return( timezone_orig );
#endif
}
char* SGTime::format_time( const struct tm* p, char* buf )
// format time
char* sgTimeFormatTime( const struct tm* p, char* buf )
{
sprintf( buf, "%d/%d/%2d %d:%02d:%02d",
p->tm_mon, p->tm_mday, p->tm_year,
p->tm_hour, p->tm_min, p->tm_sec);
return buf;
}
// SGTime* SGTime::cur_time_params = 0;

112
simgear/timing/sg_time.hxx
View File

@ -34,12 +34,6 @@
# include <config.h>
#endif
#ifdef HAVE_WINDOWS_H
# include <windows.h>
#endif
#include <GL/glut.h>
#include <simgear/compiler.h>
#ifdef FG_HAVE_STD_INCLUDES
@ -48,20 +42,7 @@
# include <time.h>
#endif
// #include <FDM/flight.hxx>
#include "timezone.h"
// #include "lowleveltime.h"
enum sgTimingOffsetType {
SG_TIME_SYS_OFFSET = 0,
SG_TIME_GMT_OFFSET = 1,
SG_TIME_LAT_OFFSET = 2,
SG_TIME_SYS_ABSOLUTE = 3,
SG_TIME_GMT_ABSOLUTE = 4,
SG_TIME_LAT_ABSOLUTE = 5
};
// Define a structure containing time parameters
@ -95,70 +76,71 @@ private:
// local sidereal time
double lst;
// the difference between the precise sidereal time algorithm
// result and the course result. course_gst + diff has good
// accuracy for the short term
// the difference between the precise / expensive sidereal time
// algorithm result and the quick course result. course_gst +
// gst_diff has pretty good accuracy over the span of a couple hours
double gst_diff;
// internal book keeping data
double last_mjd, last_dy;
int last_mn, last_yr;
public:
SGTime( const string& root );
~SGTime();
// Initialize the time related variables
void init( double lon, double lat, const string& root );
// Update the time related variables
void update( double lon, double lat, double alt_m, long int warp );
// Given lon/lat, update timezone information and local_offset
void updateLocal( double lon, double lat, const string& root );
// given Julian Date and Longitude (decimal degrees West) compute
// Local Sidereal Time, in decimal hours.
//
// Provided courtesy of ecdowney@noao.edu (Elwood Downey)
double sidereal_precise( double lng );
// return a courser but cheaper estimate of sidereal time
double sidereal_course( double lng );
// Some other stuff which were changed to SGTime members on
// questionable grounds -:)
time_t get_gmt(int year, int month, int day,
int hour, int minute, int second);
time_t get_gmt(struct tm* the_time);
inline double getJD() const { return jd; };
inline double getMjd() const { return mjd; };
inline double getLst() const { return lst; };
inline double getGst() const { return gst; };
inline time_t get_cur_time() const { return cur_time; };
inline struct tm* getGmt()const { return gmt; };
// void adjust_warp(int val) { warp += val; };
// void adjust_warp_delta(int val) { warp_delta += val; };
// Initialize the time dependent variables
void init( double lon, double lat, const string& root );
// time_t timeOffset, sgTimingOffsetType offsetType );
// Update the time dependent variables
void update( double lon, double lat, double alt_m, long int warp );
void updateLocal( double lon, double lat, const string& root );
void cal_mjd (int mn, double dy, int yr);
void utc_gst();
double sidereal_precise (double lng);
double sidereal_course(double lng);
// static SGTime *cur_time_params;
// Some other stuff which were changed to SGTime members on
// questionable grounds -:)
// time_t get_start_gmt(int year);
time_t get_gmt(int year, int month, int day,
int hour, int minute, int second);
time_t get_gmt(struct tm* the_time);
inline char* get_zonename() const { return zonename; }
char* format_time( const struct tm* p, char* buf );
long int fix_up_timezone( long int timezone_orig );
// inline int get_warp_delta() const { return warp_delta; }
};
inline time_t SGTime::get_gmt(struct tm* the_time) // this is just a wrapper
{
//printf("Using: %24s as input\n", asctime(the_time));
return get_gmt(the_time->tm_year,
the_time->tm_mon,
the_time->tm_mday,
the_time->tm_hour,
the_time->tm_min,
the_time->tm_sec);
// this is just a wrapper
inline time_t SGTime::get_gmt(struct tm* the_time) {
// printf("Using: %24s as input\n", asctime(the_time));
return get_gmt(the_time->tm_year,
the_time->tm_mon,
the_time->tm_mday,
the_time->tm_hour,
the_time->tm_min,
the_time->tm_sec);
}
// given a date in months, mn, days, dy, years, yr, return the
// modified Julian date (number of days elapsed since 1900 jan 0.5),
// mjd. Adapted from Xephem.
double sgTimeCalcMJD(int mn, double dy, int yr);
// given an mjd, calculate greenwich mean sidereal time, gst
double sgTimeCalcGST( double mjd );
// format time
char* sgTimeFormatTime( const struct tm* p, char* buf );
#endif // _SG_TIME_HXX