X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=simgear%2Ftiming%2Fsg_time.cxx;h=16d50d3ef3962056c2ee2884f14bca6b1b907c77;hb=9af5f9f094706685bae09a885fb6adf6394124c2;hp=81da67222a4cf92ba513ec4639f849b06ede7695;hpb=f0081c769716eb9bbb27c8ccef109a0aac2ad118;p=simgear.git

diff --git a/simgear/timing/sg_time.cxx b/simgear/timing/sg_time.cxx
index 81da6722..16d50d3e 100644
--- a/simgear/timing/sg_time.cxx
+++ b/simgear/timing/sg_time.cxx
@@ -4,19 +4,20 @@
 //
 // Copyright (C) 1997  Curtis L. Olson  - curt@infoplane.com
 //
-// This program is free software; you can redistribute it and/or
-// modify it under the terms of the GNU General Public License as
-// published by the Free Software Foundation; either version 2 of the
-// License, or (at your option) any later version.
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library General Public
+// License as published by the Free Software Foundation; either
+// version 2 of the License, or (at your option) any later version.
 //
-// This program is distributed in the hope that it will be useful, but
-// WITHOUT ANY WARRANTY; without even the implied warranty of
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-// General Public License for more details.
+// Library General Public License for more details.
 //
-// You should have received a copy of the GNU General Public License
-// along with this program; if not, write to the Free Software
-// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+// You should have received a copy of the GNU Library General Public
+// License along with this library; if not, write to the
+// Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+// Boston, MA  02111-1307, USA.
 //
 // $Id$
 
@@ -62,6 +63,11 @@
 #define RADHR(x)        DEGHR(x*RAD_TO_DEG)
 
 
+static const double MJD0    = 2415020.0;
+static const double J2000   = 2451545.0 - MJD0;
+static const double SIDRATE = 0.9972695677;
+
+
 SGTime::SGTime( double lon, double lat, const string& root )
 {
     FG_LOG( FG_EVENT, FG_INFO, "Initializing Time" );
@@ -74,18 +80,24 @@ SGTime::SGTime( double lon, double lat, const string& root )
     // cout << "Current local time          = " 
     //      << asctime(localtime(&cur_time)) << endl;
 
-    FGPath zone( root );
-    zone.append( "zone.tab" );
-    FG_LOG( FG_EVENT, FG_DEBUG, "Reading timezone info from: " << zone.str() );
-    tzContainer = new TimezoneContainer( zone.c_str() );
+    if ( root != "" ) {
+	FGPath zone( root );
+	zone.append( "zone.tab" );
+	FG_LOG( FG_EVENT, FG_DEBUG, "Reading timezone info from: "
+		<< zone.str() );
+	tzContainer = new TimezoneContainer( zone.c_str() );
 
-    GeoCoord location( RAD_TO_DEG * lat, RAD_TO_DEG * lon );
-    GeoCoord* nearestTz = tzContainer->getNearest(location);
+	GeoCoord location( RAD_TO_DEG * lat, RAD_TO_DEG * lon );
+	GeoCoord* nearestTz = tzContainer->getNearest(location);
 
-    FGPath name( root );
-    name.append( nearestTz->getDescription() );
-    zonename = strdup( name.c_str() );
-    // cout << "Using zonename = " << zonename << endl;
+	FGPath name( root );
+	name.append( nearestTz->getDescription() );
+	zonename = strdup( name.c_str() );
+	// cout << "Using zonename = " << zonename << endl;
+    } else {
+	tzContainer = NULL;
+	zonename = NULL;
+    }
 }
 
 
@@ -94,9 +106,16 @@ SGTime::SGTime( const string& root ) {
 }
 
 
+SGTime::SGTime() {
+    SGTime( 0.0, 0.0, "" );
+}
+
+
 SGTime::~SGTime()
 {
-    delete tzContainer;
+    if ( tzContainer != NULL ) {
+	delete tzContainer;
+    }
 
     if ( zonename != NULL ) {
 	delete zonename;
@@ -399,7 +418,7 @@ time_t sgTimeGetGMT(int year, int month, int day, int hour, int min, int sec)
 #       define TIMEZONE_OFFSET_WORKS 1
 #   endif
 
-    long int start = mktime(&mt);
+    time_t start = mktime(&mt);
 
     FG_LOG( FG_EVENT, FG_DEBUG, "start1 = " << start );
     // the ctime() call can screw up time progression on some versions