X-Git-Url: https://git.mxchange.org/?a=blobdiff_plain;f=simgear%2Fephemeris%2FcelestialBody.cxx;h=4e8873925b65ef7290aba629afcf390648d4ac29;hb=f19e83dcf10d5fced3d799c884a4654d7ada6548;hp=ae6a792982890b5aa3f22198c109371870adf7b9;hpb=557fade4a7df3f030b943ba6114c3c566c57b73c;p=simgear.git

diff --git a/simgear/ephemeris/celestialBody.cxx b/simgear/ephemeris/celestialBody.cxx
index ae6a7929..4e887392 100644
--- a/simgear/ephemeris/celestialBody.cxx
+++ b/simgear/ephemeris/celestialBody.cxx
@@ -15,19 +15,15 @@
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
- * 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.
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  *
  * $Id$
  **************************************************************************/
 
 #include <simgear/debug/logstream.hxx>
 
-#ifdef SG_MATH_EXCEPTION_CLASH
-#  define exception c_exception
-#endif
 #include <math.h>
 
 #include "celestialBody.hxx"
@@ -158,22 +154,112 @@ double CelestialBody::sgCalcEccAnom(double M, double e)
   return eccAnom;
 }
 
+/*****************************************************************************
+ * inline CelestialBody::CelestialBody
+ * public constructor for a generic celestialBody object.
+ * initializes the 6 primary orbital elements. The elements are:
+ * N: longitude of the ascending node
+ * i: inclination to the ecliptic
+ * w: argument of perihelion
+ * a: semi-major axis, or mean distance from the sun
+ * e: eccenticity
+ * M: mean anomaly
+ * Each orbital element consists of a constant part and a variable part that 
+ * gradually changes over time. 
+ *
+ * Argumetns:
+ * the 13 arguments to the constructor constitute the first, constant 
+ * ([NiwaeM]f) and the second variable ([NiwaeM]s) part of the orbital 
+ * elements. The 13th argument is the current time. Note that the inclination
+ * is written with a capital (If, Is), because 'if' is a reserved word in the 
+ * C/C++ programming language.
+ ***************************************************************************/ 
+CelestialBody::CelestialBody(double Nf, double Ns,
+				    double If, double Is,
+				    double wf, double ws,
+				    double af, double as,
+				    double ef, double es,
+				    double Mf, double Ms, double mjd)
+{
+  NFirst = Nf;     NSec = Ns;
+  iFirst = If;     iSec = Is;
+  wFirst = wf;     wSec = ws;
+  aFirst = af;     aSec = as;
+  eFirst = ef;     eSec = es;
+  MFirst = Mf;     MSec = Ms;
+  updateOrbElements(mjd);
+}
 
+CelestialBody::CelestialBody(double Nf, double Ns,
+				    double If, double Is,
+				    double wf, double ws,
+				    double af, double as,
+				    double ef, double es,
+				    double Mf, double Ms)
+{
+  NFirst = Nf;     NSec = Ns;
+  iFirst = If;     iSec = Is;
+  wFirst = wf;     wSec = ws;
+  aFirst = af;     aSec = as;
+  eFirst = ef;     eSec = es;
+  MFirst = Mf;     MSec = Ms;
+}
 
+/****************************************************************************
+ * inline void CelestialBody::updateOrbElements(double mjd)
+ * given the current time, this private member calculates the actual 
+ * orbital elements
+ *
+ * Arguments: double mjd: the current modified julian date:
+ *
+ * return value: none
+ ***************************************************************************/
+void CelestialBody::updateOrbElements(double mjd)
+{
+  double actTime = sgCalcActTime(mjd);
+   M = SGD_DEGREES_TO_RADIANS * (MFirst + (MSec * actTime));
+   w = SGD_DEGREES_TO_RADIANS * (wFirst + (wSec * actTime));
+   N = SGD_DEGREES_TO_RADIANS * (NFirst + (NSec * actTime));
+   i = SGD_DEGREES_TO_RADIANS * (iFirst + (iSec * actTime));
+   e = eFirst + (eSec * actTime);
+   a = aFirst + (aSec * actTime);
+}
 
+/*****************************************************************************
+ * inline double CelestialBody::sgCalcActTime(double mjd)
+ * this private member function returns the offset in days from the epoch for
+ * wich the orbital elements are calculated (Jan, 1st, 2000).
+ * 
+ * Argument: the current time
+ *
+ * return value: the (fractional) number of days until Jan 1, 2000.
+ ****************************************************************************/
+double CelestialBody::sgCalcActTime(double mjd)
+{
+  return (mjd - 36523.5);
+}
 
+/*****************************************************************************
+ * inline void CelestialBody::getPos(double* ra, double* dec)
+ * gives public access to Right Ascension and declination
+ *
+ ****************************************************************************/
+void CelestialBody::getPos(double* ra, double* dec)
+{
+  *ra  = rightAscension;
+  *dec = declination;
+}
 
-
-
-
-
-
-
-
-
-
-
-
-
+/*****************************************************************************
+ * inline void CelestialBody::getPos(double* ra, double* dec, double* magnitude
+ * gives public acces to the current Right ascension, declination, and 
+ * magnitude
+ ****************************************************************************/
+void CelestialBody::getPos(double* ra, double* dec, double* magn)
+{
+  *ra = rightAscension;
+  *dec = declination;
+  *magn = magnitude;
+}