1
0
Fork 0
flightgear/Scenery/orbits.h

85 lines
2.6 KiB
C

/**************************************************************************
* orbits.h - calculates the orbital elements of the sun, moon and planets.
* For inclusion in flight gear
*
* Written 1997 by Durk Talsma, started October 19, 1997.
*
* 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 program 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.
*
* 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.
*
* $Id$
* (Log is kept at end of this file)
**************************************************************************/
#ifndef ORBITS_H
#define ORBITS_H
#include <stdio.h>
#include <math.h>
#include "../Time/fg_time.h"
#define STANDARDEPOCH 2000
#define PIOVER180 1.74532925199433E-002
struct SunPos {
double xs;
double ys;
};
struct OrbElements {
double NFirst; /* longitude of the ascending node first part */
double NSec; /* longitude of the ascending node second part */
double iFirst; /* inclination to the ecliptic first part */
double iSec; /* inclination to the ecliptic second part */
double wFirst; /* first part of argument of perihelion */
double wSec; /* second part of argument of perihelion */
double aFirst; /* semimayor axis first part*/
double aSec; /* semimayor axis second part */
double eFirst; /* eccentricity first part */
double eSec; /* eccentricity second part */
double MFirst; /* Mean anomaly first part */
double MSec; /* Mean anomaly second part */
double N, i, w, a, e, M; /* the resultant orbital elements, obtained from the former */
};
struct CelestialCoord {
double RightAscension;
double Declination;
double distance;
};
double fgDegToRad(double angle);
double fgCalcEccAnom(double M, double e);
double fgCalcActTime(struct fgTIME t);
void fgReadOrbElements(struct OrbElements *dest, FILE *src);
void fgSolarSystemInit(struct fgTIME t);
void fgSolarSystemUpdate(struct OrbElements *planets, struct fgTIME t);
#endif /* ORBITS_H */
/* $Log$
/* Revision 1.1 1997/10/25 03:16:10 curt
/* Initial revision of code contributed by Durk Talsma.
/*
*/