/**************************************************************************
- * moon.c
- * Written by Durk Talsma. Started October 1997, for the flight gear project.
+ * moon.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
* $Id$
* (Log is kept at end of this file)
**************************************************************************/
+#include <Flight/flight.hxx>
+#include <string.h>
+#include "moon.hxx"
+#include <Debug/logstream.hxx>
+#include <Objects/texload.h>
-#include <config.h>
-#ifdef HAVE_WINDOWS_H
-# include <windows.h>
+#ifdef __BORLANDC__
+# define exception c_exception
#endif
-
#include <math.h>
-#include <GL/glut.h>
-#include <XGL/xgl.h>
-
-#include <Aircraft/aircraft.h>
-#include <Debug/fg_debug.h>
-#include <Include/fg_constants.h>
-#include <Include/general.h>
-#include <Main/views.hxx>
-#include <Time/fg_time.h>
-
-#include "orbits.hxx"
-#include "moon.hxx"
-
-
-struct CelestialCoord moonPos;
-
-static float xMoon, yMoon, zMoon;
-static GLint moon = 0;
+static GLuint moon_texid;
+static GLubyte *moon_texbuf;
+
+/*************************************************************************
+ * Moon::Moon(fgTIME *t)
+ * Public constructor for class Moon. Initializes the orbital elements and
+ * sets up the moon texture.
+ * Argument: The current time.
+ * the hard coded orbital elements for Moon are passed to
+ * CelestialBody::CelestialBody();
+ ************************************************************************/
+Moon::Moon(fgTIME *t) :
+ CelestialBody(125.1228, -0.0529538083,
+ 5.1454, 0.00000,
+ 318.0634, 0.1643573223,
+ 60.266600, 0.000000,
+ 0.054900, 0.000000,
+ 115.3654, 13.0649929509, t)
+{
+ string tpath, fg_tpath;
+ int width, height;
+
+ FG_LOG( FG_GENERAL, FG_INFO, "Initializing Moon Texture");
+#ifdef GL_VERSION_1_1
+ xglGenTextures(1, &moon_texid);
+ xglBindTexture(GL_TEXTURE_2D, moon_texid);
+#elif GL_EXT_texture_object
+ xglGenTexturesEXT(1, &moon_texid);
+ xglBindTextureEXT(GL_TEXTURE_2D, moon_texid);
+#else
+# error port me
+#endif
+ glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+ glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-/* --------------------------------------------------------------
- This section contains the code that calculates the actual
- position of the moon in the night sky.
-----------------------------------------------------------------*/
-struct CelestialCoord fgCalculateMoon(struct OrbElements params,
- struct OrbElements sunParams,
- struct fgTIME t)
-{
- struct CelestialCoord
- geocCoord, topocCoord;
+ // load in the texture data
+ tpath = current_options.get_fg_root() + "/Textures/" + "moon.rgb";
- double
+ if ( (moon_texbuf = read_rgb_texture(tpath.c_str(), &width, &height))
+ == NULL )
+ {
+ // Try compressed
+ fg_tpath = tpath + ".gz";
+ if ( (moon_texbuf = read_rgb_texture(fg_tpath.c_str(), &width, &height))
+ == NULL )
+ {
+ FG_LOG( FG_GENERAL, FG_ALERT,
+ "Error in loading moon texture " << tpath );
+ exit(-1);
+ }
+ }
+
+ glTexImage2D( GL_TEXTURE_2D,
+ 0,
+ GL_RGB,
+ 256, 256,
+ 0,
+ GL_RGB, GL_UNSIGNED_BYTE,
+ moon_texbuf);
+}
+/*****************************************************************************
+ * void Moon::updatePosition(fgTIME *t, Star *ourSun)
+ * this member function calculates the actual topocentric position (i.e.)
+ * the position of the moon as seen from the current position on the surface
+ * of the moon.
+ ****************************************************************************/
+void Moon::updatePosition(fgTIME *t, Star *ourSun)
+{
+ double
eccAnom, ecl, lonecl, latecl, actTime,
xv, yv, v, r, xh, yh, zh, xg, yg, zg, xe, ye, ze,
- Ls, Lm, D, F, mpar, gclat, rho, HA, g;
+ Ls, Lm, D, F, mpar, gclat, rho, HA, g,
+ geoRa, geoDec;
- fgAIRCRAFT *a;
- fgFLIGHT *f;
+ fgAIRCRAFT *air;
+ FGState *f;
- a = ¤t_aircraft;
- f = a->flight;
-
- /* calculate the angle between ecliptic and equatorial coordinate
- * system, in Radians */
+ air = ¤t_aircraft;
+ f = air->fdm_state;
+
+ updateOrbElements(t);
actTime = fgCalcActTime(t);
- ecl = ((DEG_TO_RAD * 23.4393) - (DEG_TO_RAD * 3.563E-7) * actTime);
- /*ecl = 0.409093 - 6.2186E-9 * actTime; */
-
- /* calculate the eccentric anomaly */
- eccAnom = fgCalcEccAnom(params.M, params.e);
- /* calculate the moon's distance (r) and true anomaly (v) */
- xv = params.a * ( cos(eccAnom) - params.e);
- yv = params.a * ( sqrt(1.0 - params.e*params.e) * sin(eccAnom));
- v =atan2(yv, xv);
- r = sqrt(xv*xv + yv*yv);
-
- /* estimate the geocentric rectangular coordinates here */
- xh = r * (cos (params.N) * cos (v + params.w) -
- sin (params.N) * sin (v + params.w) * cos (params.i));
- yh = r * (sin (params.N) * cos (v + params.w) +
- cos (params.N) * sin (v + params.w) * cos (params.i));
- zh = r * (sin(v + params.w) * sin(params.i));
+ // calculate the angle between ecliptic and equatorial coordinate system
+ // in Radians
+ ecl = ((DEG_TO_RAD * 23.4393) - (DEG_TO_RAD * 3.563E-7) * actTime);
+ eccAnom = fgCalcEccAnom(M, e); // Calculate the eccentric anomaly
+ xv = a * (cos(eccAnom) - e);
+ yv = a * (sqrt(1.0 - e*e) * sin(eccAnom));
+ v = atan2(yv, xv); // the moon's true anomaly
+ r = sqrt (xv*xv + yv*yv); // and its distance
- /* calculate the ecliptic latitude and longitude here */
- lonecl = atan2( yh, xh);
- latecl = atan2( zh, sqrt( xh*xh + yh*yh));
-
- /* calculate a number of perturbations, i.e. disturbances caused by
- * the gravitational influence of the sun and the other mayor
- * planets. The largest of these even have their own names */
- Ls = sunParams.M + sunParams.w;
- Lm = params.M + params.w + params.N;
+ // estimate the geocentric rectangular coordinates here
+ xh = r * (cos(N) * cos (v+w) - sin (N) * sin(v+w) * cos(i));
+ yh = r * (sin(N) * cos (v+w) + cos (N) * sin(v+w) * cos(i));
+ zh = r * (sin(v+w) * sin(i));
+
+ // calculate the ecliptic latitude and longitude here
+ lonecl = atan2 (yh, xh);
+ latecl = atan2(zh, sqrt(xh*xh + yh*yh));
+
+ /* Calculate a number of perturbatioin, i.e. disturbances caused by the
+ * gravitational infuence of the sun and the other major planets.
+ * The largest of these even have a name */
+ Ls = ourSun->getM() + ourSun->getw();
+ Lm = M + w + N;
D = Lm - Ls;
- F = Lm - params.N;
+ F = Lm - N;
- lonecl += DEG_TO_RAD * (
- - 1.274 * sin (params.M - 2*D) /* the Evection */
- + 0.658 * sin (2 * D) /* the Variation */
- - 0.186 * sin (sunParams.M) /* the yearly variation */
- - 0.059 * sin (2*params.M - 2*D)
- - 0.057 * sin (params.M - 2*D + sunParams.M)
- + 0.053 * sin (params.M + 2*D)
- + 0.046 * sin (2*D - sunParams.M)
- + 0.041 * sin (params.M - sunParams.M)
- - 0.035 * sin (D) /* the Parallactic Equation */
- - 0.031 * sin (params.M + sunParams.M)
- - 0.015 * sin (2*F - 2*D)
- + 0.011 * sin (params.M - 4*D)
+ lonecl += DEG_TO_RAD * (-1.274 * sin (M - 2*D)
+ +0.658 * sin (2*D)
+ -0.186 * sin(ourSun->getM())
+ -0.059 * sin(2*M - 2*D)
+ -0.057 * sin(M - 2*D + ourSun->getM())
+ +0.053 * sin(M + 2*D)
+ +0.046 * sin(2*D - ourSun->getM())
+ +0.041 * sin(M - ourSun->getM())
+ -0.035 * sin(D)
+ -0.031 * sin(M + ourSun->getM())
+ -0.015 * sin(2*F - 2*D)
+ +0.011 * sin(M - 4*D)
);
- latecl += DEG_TO_RAD * (
- - 0.173 * sin (F - 2*D)
- - 0.055 * sin (params.M - F - 2*D)
- - 0.046 * sin (params.M + F - 2*D)
- + 0.033 * sin (F + 2*D)
- + 0.017 * sin (2 * params.M + F)
+ latecl += DEG_TO_RAD * (-0.173 * sin(F-2*D)
+ -0.055 * sin(M - F - 2*D)
+ -0.046 * sin(M + F - 2*D)
+ +0.033 * sin(F + 2*D)
+ +0.017 * sin(2*M + F)
);
-
- r += (
- - 0.58 * cos(params.M - 2*D)
- - 0.46 * cos(2*D)
+ r += (-0.58 * cos(M - 2*D)
+ -0.46 * cos(2*D)
);
-
+ FG_LOG(FG_GENERAL, FG_INFO, "Running moon update");
xg = r * cos(lonecl) * cos(latecl);
yg = r * sin(lonecl) * cos(latecl);
zg = r * sin(latecl);
-
- xe = xg;
- ye = yg * cos(ecl) - zg * sin(ecl);
- ze = yg * sin(ecl) + zg * cos(ecl);
-
+ xe = xg;
+ ye = yg * cos(ecl) -zg * sin(ecl);
+ ze = yg * sin(ecl) +zg * cos(ecl);
+
+ geoRa = atan2(ye, xe);
+ geoDec = atan2(ze, sqrt(xe*xe + ye*ye));
+
+ // Given the moon's geocentric ra and dec, calculate its
+ // topocentric ra and dec. i.e. the position as seen from the
+ // surface of the earth, instead of the center of the earth
+
+ // First calculates the moon's parrallax, that is, the apparent size of the
+ // (equatorial) radius of the earth, as seen from the moon
+ mpar = asin ( 1 / r);
+ gclat = f->get_Latitude() - 0.003358 *
+ sin (2 * DEG_TO_RAD * f->get_Latitude() );
+ rho = 0.99883 + 0.00167 * cos(2 * DEG_TO_RAD * f->get_Latitude());
+ if (geoRa < 0)
+ geoRa += (2*FG_PI);
-
- geocCoord.RightAscension = atan2(ye, xe);
- geocCoord.Declination = atan2(ze, sqrt(xe*xe + ye*ye));
-
- /* New since 25 december 1997 */
- /* Calculate the moon's topocentric position instead of it's geocentric! */
-
- /* calculate the moon's parrallax, i.e. the apparent size of the
- * (equatorial) radius of the Earth, as seen from the moon */
- mpar = asin( 1 / r);
- gclat = FG_Latitude - 0.083358 * sin (2 * DEG_TO_RAD * FG_Latitude);
- rho = 0.99883 + 0.00167 * cos(2 * DEG_TO_RAD * FG_Latitude);
-
- if (geocCoord.RightAscension < 0)
- geocCoord.RightAscension += (2*FG_PI);
-
- HA = t.lst - (3.8197186 * geocCoord.RightAscension);
-
- g = atan (tan(gclat) / cos( (HA / 3.8197186)));
-
-
-
- topocCoord.RightAscension = geocCoord.RightAscension -
- mpar * rho * cos (gclat) * sin (HA) / cos (geocCoord.Declination);
- topocCoord.Declination = geocCoord.Declination -
- mpar * rho * sin (gclat) * sin (g - geocCoord.Declination) / sin (g);
- return topocCoord;
+ HA = t->lst - (3.8197186 * geoRa);
+ g = atan (tan(gclat) / cos ((HA / 3.8197186)));
+ rightAscension = geoRa - mpar * rho * cos(gclat) * sin(HA) / cos (geoDec);
+ declination = geoDec - mpar * rho * sin (gclat) * sin (g - geoDec) / sin(g);
}
-void fgMoonInit( void ) {
- GLfloat moonColor[4] = {0.85, 0.75, 0.35, 1.0};
- GLfloat black[4] = { 0.0, 0.0, 0.0, 1.0 };
-
- fgPrintf( FG_ASTRO, FG_INFO, "Initializing the Moon\n");
- fgSolarSystemUpdate(&(pltOrbElements[1]), cur_time_params);
- moonPos = fgCalculateMoon(pltOrbElements[1], pltOrbElements[0],
- cur_time_params);
- fgPrintf( FG_ASTRO, FG_DEBUG,
- "Moon found at %f (ra), %f (dec)\n", moonPos.RightAscension,
- moonPos.Declination);
+/************************************************************************
+ * void Moon::newImage(float ra, float dec)
+ *
+ * This function regenerates a new visual image of the moon, which is added to
+ * solarSystem display list.
+ *
+ * Arguments: Right Ascension and declination
+ *
+ * return value: none
+ **************************************************************************/
+void Moon::newImage(float ra, float dec)
+{
+ glEnable(GL_TEXTURE_2D);
+ glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+ glBindTexture(GL_TEXTURE_2D, moon_texid);
+
+ //xglRotatef(-90, 0.0, 0.0, 1.0);
+ xglRotatef(((RAD_TO_DEG * ra)- 90.0), 0.0, 0.0, 1.0);
+ xglRotatef((RAD_TO_DEG * dec), 1.0, 0.0, 0.0);
+
+ FG_LOG( FG_GENERAL, FG_INFO,
+ "Ra = (" << (RAD_TO_DEG *ra)
+ << "), Dec= (" << (RAD_TO_DEG *dec) << ")" );
+ xglTranslatef(0.0, 58600.0, 0.0);
+ Object = gluNewQuadric();
+ gluQuadricTexture( Object, GL_TRUE );
+ gluSphere( Object, 1367, 12, 12 );
+ glDisable(GL_TEXTURE_2D);
+}
- xMoon = 60000.0 * cos(moonPos.RightAscension) * cos(moonPos.Declination);
- yMoon = 60000.0 * sin(moonPos.RightAscension) * cos(moonPos.Declination);
- zMoon = 60000.0 * sin(moonPos.Declination);
- if (moon) {
- xglDeleteLists (moon, 1);
- }
- moon = xglGenLists (1);
- xglNewList (moon, GL_COMPILE);
-
- xglMaterialfv (GL_FRONT, GL_AMBIENT, black);
- xglMaterialfv (GL_FRONT, GL_DIFFUSE, moonColor);
- xglPushMatrix ();
- xglTranslatef (xMoon, yMoon, zMoon);
- xglScalef (1400, 1400, 1400);
-
- glutSolidSphere (1.0, 10, 10);
- xglPopMatrix ();
- xglEndList ();
-}
-/* Draw the moon */
-void fgMoonRender( void ) {
- xglCallList(moon);
-}
-/* $Log$
-/* Revision 1.1 1998/04/22 13:21:28 curt
-/* C++ - ifing the code a bit.
-/*
- * Revision 1.9 1998/04/18 04:13:56 curt
- * Moved fg_debug.c to it's own library.
- *
- * Revision 1.8 1998/04/03 21:52:49 curt
- * Converting to Gnu autoconf system.
- *
- * Revision 1.7 1998/02/23 19:07:54 curt
- * Incorporated Durk's Astro/ tweaks. Includes unifying the sun position
- * calculation code between sun display, and other FG sections that use this
- * for things like lighting.
- *
- * Revision 1.6 1998/02/07 15:29:32 curt
- * Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
- * <chotchkiss@namg.us.anritsu.com>
- *
- * Revision 1.5 1998/02/02 20:53:21 curt
- * To version 0.29
- *
- * Revision 1.4 1998/01/27 00:47:46 curt
- * Incorporated Paul Bleisch's <bleisch@chromatic.com> new debug message
- * system and commandline/config file processing code.
- *
- * Revision 1.3 1998/01/19 19:26:57 curt
- * Merged in make system changes from Bob Kuehne <rpk@sgi.com>
- * This should simplify things tremendously.
- *
- * Revision 1.2 1998/01/19 18:40:16 curt
- * Tons of little changes to clean up the code and to remove fatal errors
- * when building with the c++ compiler.
- *
- * Revision 1.1 1998/01/07 03:16:16 curt
- * Moved from .../Src/Scenery/ to .../Src/Astro/
- *
- * Revision 1.16 1998/01/06 01:20:24 curt
- * Tweaks to help building with MSVC++
- *
- * Revision 1.15 1998/01/05 18:44:35 curt
- * Add an option to advance/decrease time from keyboard.
- *
- * Revision 1.14 1997/12/30 20:47:50 curt
- * Integrated new event manager with subsystem initializations.
- *
- * Revision 1.13 1997/12/30 16:41:00 curt
- * Added log at end of file.
- *
- */
projects / flightgear.git / blobdiff