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SGTime: use SGGeod, quieter init.

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It's common to use SGTime to calculate the the Julian Date, without providing time-zone information. Don't warn in these cases, since the behaviour is fine.
This commit is contained in:
James Turner
2012-09-24 00:02:11 +01:00
parent be405d2311
commit 89d30acbc5
3 changed files with 63 additions and 68 deletions
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19
simgear/math/SGGeod.hxx
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@@ -82,9 +82,12 @@ public:
/// Set the geodetic elevation from the argument given in feet
void setElevationFt(double elevation);
// Compare two geodetic positions for equality
/// Compare two geodetic positions for equality
bool operator == ( const SGGeod & other ) const;
/// check the Geod contains sane values (finite, inside appropriate
/// ranges for lat/lon)
bool isValid() const;
private:
/// This one is private since construction is not unique if you do
/// not know the units of the arguments. Use the factory methods for
@@ -345,6 +348,20 @@ SGGeod::operator == ( const SGGeod & other ) const
_elevation == other._elevation;
}
inline
bool
SGGeod::isValid() const
{
if (std::isnan(_lon) || std::isnan(_lat)) return false;
#ifdef SG_GEOD_NATIVE_DEGREE
return (_lon >= -180.0) && (_lon <= 180.0) &&
(_lat >= -90.0) && (_lat <= 90.0);
#else
return (_lon >= -SGD_PI) && (_lon <= SGD_PI) &&
(_lat >= -SGD_PI_2) && (_lat <= SGD_PI_2);
#endif
}
/// Output to an ostream
template<typename char_type, typename traits_type>
inline

89
simgear/timing/sg_time.cxx
View File

@@ -65,12 +65,11 @@ static const double MJD0 = 2415020.0;
static const double J2000 = 2451545.0 - MJD0;
static const double SIDRATE = 0.9972695677;
// tzContainer stores all the current Timezone control points/
std::auto_ptr<SGTimeZoneContainer> static_tzContainer;
void SGTime::init( double lon_rad, double lat_rad,
const string& root, time_t init_time )
void SGTime::init( const SGGeod& location, const SGPath& root, time_t init_time )
{
SG_LOG( SG_EVENT, SG_INFO, "Initializing Time" );
gst_diff = -9999.0;
if ( init_time ) {
@@ -79,51 +78,49 @@ void SGTime::init( double lon_rad, double lat_rad,
cur_time = time(NULL);
}
SG_LOG( SG_EVENT, SG_INFO,
SG_LOG( SG_EVENT, SG_DEBUG,
"Current greenwich mean time = " << asctime(gmtime(&cur_time)));
SG_LOG( SG_EVENT, SG_INFO,
SG_LOG( SG_EVENT, SG_DEBUG,
"Current local time = " << asctime(localtime(&cur_time)));
if ( !root.empty()) {
SGPath zone( root );
zone.append( "zone.tab" );
SG_LOG( SG_EVENT, SG_INFO, "Reading timezone info from: "
<< zone.str() );
tzContainer = new SGTimeZoneContainer( zone.c_str() );
SGGeod location(SGGeod::fromRad(lon_rad, lat_rad));
SGTimeZone* nearestTz = tzContainer->getNearest(location);
if ( !root.isNull()) {
if (!static_tzContainer.get()) {
SGPath zone( root );
zone.append( "zone.tab" );
SG_LOG( SG_EVENT, SG_INFO, "Reading timezone info from: "
<< zone.str() );
static_tzContainer.reset(new SGTimeZoneContainer( zone.c_str() ));
}
SGTimeZone* nearestTz = static_tzContainer->getNearest(location);
SGPath name( root );
name.append( nearestTz->getDescription() );
zonename = name.str();
SG_LOG( SG_EVENT, SG_INFO, "Using zonename = " << zonename );
SG_LOG( SG_EVENT, SG_DEBUG, "Using zonename = " << zonename );
} else {
SG_LOG( SG_EVENT, SG_INFO, "*** NO TIME ZONE NAME ***" );
tzContainer = NULL;
zonename.erase();
}
}
SGTime::SGTime( double lon_rad, double lat_rad, const string& root,
time_t init_time )
SGTime::SGTime( const SGGeod& location, const SGPath& root,
time_t init_time )
{
init( lon_rad, lat_rad, root, init_time );
init(location, root, init_time);
}
SGTime::SGTime( const string& root ) {
init( 0.0, 0.0, root, 0 );
SGTime::SGTime( const SGPath& root ) {
init( SGGeod(), root, 0 );
}
SGTime::SGTime() {
init( 0.0, 0.0, "", 0 );
init( SGGeod(), SGPath(), 0 );
}
SGTime::~SGTime()
{
delete tzContainer;
}
@@ -187,8 +184,7 @@ static double sidereal_course( time_t cur_time, const struct tm *gmt, double lng
// Update the time related variables
void SGTime::update( double lon_rad, double lat_rad,
time_t ct, long int warp )
void SGTime::update( const SGGeod& location, time_t ct, long int warp )
{
double gst_precise, gst_course;
@@ -196,8 +192,6 @@ void SGTime::update( double lon_rad, double lat_rad,
tm * gmt = &m_gmt;
SG_LOG( SG_EVENT, SG_DEBUG, "Updating time" );
// get current Unix calendar time (in seconds)
// warp += warp_delta;
if ( ct ) {
@@ -235,57 +229,40 @@ void SGTime::update( double lon_rad, double lat_rad,
if ( gst_diff < -100.0 ) {
// first time through do the expensive calculation & cheap
// calculation to get the difference.
SG_LOG( SG_EVENT, SG_INFO, " First time, doing precise gst" );
SG_LOG( SG_EVENT, SG_DEBUG, " First time, doing precise gst" );
gst_precise = gst = sidereal_precise( mjd, 0.00 );
gst_course = sidereal_course( cur_time, gmt, 0.00 );
gst_diff = gst_precise - gst_course;
lst = sidereal_course( cur_time, gmt,
-(lon_rad * SGD_RADIANS_TO_DEGREES) ) + gst_diff;
-location.getLongitudeDeg() ) + gst_diff;
} else {
// course + difference should drift off very slowly
gst = sidereal_course( cur_time, gmt, 0.00 ) + gst_diff;
lst = sidereal_course( cur_time, gmt,
-(lon_rad * SGD_RADIANS_TO_DEGREES) ) + gst_diff;
-location.getLongitudeDeg() ) + gst_diff;
}
SG_LOG( SG_EVENT, SG_DEBUG,
" Current lon=0.00 Sidereal Time = " << gst );
SG_LOG( SG_EVENT, SG_DEBUG,
" Current LOCAL Sidereal Time = " << lst << " ("
<< sidereal_precise( mjd, -(lon_rad * SGD_RADIANS_TO_DEGREES) )
<< sidereal_precise( mjd, -location.getLongitudeDeg() )
<< ") (diff = " << gst_diff << ")" );
}
// Given lon/lat, update timezone information and local_offset
void SGTime::updateLocal( double lon_rad, double lat_rad, const string& root ) {
// sanity checking
if ( lon_rad < -SGD_PI || lon_rad> SGD_PI ) {
// not within -180 ... 180
lon_rad = 0.0;
}
if ( lat_rad < -SGD_PI_2 || lat_rad > SGD_PI_2 ) {
// not within -90 ... 90
lat_rad = 0.0;
}
if ( lon_rad != lon_rad ) {
// only true if lon_rad == nan
SG_LOG( SG_EVENT, SG_ALERT,
" Detected lon_rad == nan, resetting to 0.0" );
lon_rad = 0.0;
}
if ( lat_rad != lat_rad ) {
// only true if lat_rad == nan
SG_LOG( SG_EVENT, SG_ALERT,
" Detected lat_rad == nan, resetting to 0.0" );
lat_rad = 0.0;
void SGTime::updateLocal( const SGGeod& aLocation, const string& root ) {
SGGeod location(aLocation);
if (!aLocation.isValid()) {
location = SGGeod();
}
time_t currGMT;
time_t aircraftLocalTime;
SGGeod location(SGGeod::fromRad(lon_rad, lat_rad));
SGTimeZone* nearestTz = tzContainer->getNearest(location);
SGTimeZone* nearestTz = static_tzContainer->getNearest(location);
SGPath zone( root );
zone.append ( nearestTz->getDescription() );
zonename = zone.str();

23
simgear/timing/sg_time.hxx
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@@ -36,10 +36,13 @@
#include <simgear/compiler.h>
#include <ctime>
#include <memory> // for std::auto_ptr
#include <string>
#include <simgear/timing/timezone.h>
// forward decls
class SGPath;
class SGGeod;
/**
* A class to calculate and manage a variety of time parameters.
* The SGTime class provides many real-world time values. It
@@ -63,8 +66,6 @@
class SGTime {
private:
// tzContainer stores all the current Timezone control points/
SGTimeZoneContainer* tzContainer;
// Points to the current local timezone name;
std::string zonename;
@@ -96,7 +97,7 @@ private:
double gst_diff;
/** init common constructor code */
void init( double lon_rad, double lat_rad, const std::string& root,
void init( const SGGeod& location, const SGPath& root,
time_t init_time );
public:
@@ -120,14 +121,14 @@ public:
* @param root root path point to data file location (timezone, etc.)
* @param init_time provide an initialization time, 0 means use
current clock time */
SGTime( double lon_rad, double lat_rad, const std::string& root,
time_t init_time );
SGTime( const SGGeod& location, const SGPath& root,
time_t init_time );
/**
* Create an instance given a data file path.
* @param root root path point to data file location (timezone, etc.)
*/
SGTime( const std::string& root );
SGTime( const SGPath& root );
/** Destructor */
~SGTime();
@@ -145,7 +146,7 @@ public:
clock time
* @param warp an optional time offset specified in seconds. This
* allows us to advance or rewind "time" if we choose to. */
void update( double lon_rad, double lat_rad, time_t ct, long int warp );
void update( const SGGeod& location, time_t ct, long int warp );
/**
* Given lon/lat, update timezone information and local_offset
@@ -157,7 +158,7 @@ public:
* @param lon_rad current longitude (radians)
* @param lat_rad current latitude (radians)
* @param root base path containing time zone directory */
void updateLocal( double lon_rad, double lat_rad, const std::string& root );
void updateLocal( const SGGeod& location, const std::string& root );
/** @return current system/unix time in seconds */
inline time_t get_cur_time() const { return cur_time; };