New textured moon and rewritten/restructured Astro code contributed by Durk

Talsma.
2009-09-15 18:31:31 +02:00
parent 38631c9eb3
commit 001a2c89e7
33 changed files with 2142 additions and 1524 deletions
@@ -0,0 +1,64 @@
+/**************************************************************************
+ * saturn.cxx
+ * Written by Durk Talsma. Originally started October 1997, for distribution  
+ * with the FlightGear project. Version 2 was written in August and 
+ * September 1998. This code is based upon algorithms and data kindly 
+ * provided by Mr. Paul Schlyter. (pausch@saaf.se). 
+ *
+ * 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)
+ **************************************************************************/
+#include "saturn.hxx"
+
+/*************************************************************************
+ * Saturn::Saturn(fgTIME *t)
+ * Public constructor for class Saturn
+ * Argument: The current time.
+ * the hard coded orbital elements for Saturn are passed to 
+ * CelestialBody::CelestialBody();
+ ************************************************************************/
+Saturn::Saturn(fgTIME *t) :
+  CelestialBody(113.6634,   2.3898000E-5,
+		2.4886,	   -1.081E-7,
+		339.3939,   2.9766100E-5,
+		9.5547500,  0.000000,
+		0.055546,  -9.499E-9,
+		316.9670,   0.03344422820, t)
+{
+}
+
+/*************************************************************************
+ * void Saturn::updatePosition(fgTIME *t, Star *ourSun)
+ * 
+ * calculates the current position of Saturn, by calling the base class,
+ * CelestialBody::updatePosition(); The current magnitude is calculated using 
+ * a Saturn specific equation
+ *************************************************************************/
+void Saturn::updatePosition(fgTIME *t, Star *ourSun)
+{
+  CelestialBody::updatePosition(t, ourSun);
+  
+  double actTime = fgCalcActTime(t);
+  double ir = 0.4897394;
+  double Nr = 2.9585076 + 6.6672E-7*actTime;
+  double B = asin (sin(declination) * cos(ir) - 
+		   cos(declination) * sin(ir) *
+		   sin(rightAscension - Nr));
+  double ring_magn = -2.6 * sin(fabs(B)) + 1.2 * pow(sin(B), 2);
+  magnitude = -9.0 + 5*log10(r*R) + 0.044 * FV + ring_magn;
+}
+