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

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Talsma.
This commit is contained in:
curt
2009-09-15 18:31:31 +02:00
committed by Tim Moore
parent 38631c9eb3
commit 001a2c89e7
33 changed files with 2142 additions and 1524 deletions
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Astro/moon.cxx
+174 -230
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@@ -1,6 +1,9 @@
/**************************************************************************
* 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
@@ -19,268 +22,209 @@
* $Id$
* (Log is kept at end of this file)
**************************************************************************/
#include <Flight/flight.h>
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#ifdef HAVE_WINDOWS_H
# include <windows.h>
#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.hxx>
#include "orbits.hxx"
#include <string.h>
#include "moon.hxx"
#include <Debug/fg_debug.h>
#include <Objects/texload.h>
static GLuint moon_texid;
static GLubyte *moon_texbuf;
struct CelestialCoord moonPos;
static float xMoon, yMoon, zMoon;
static GLint moon = 0;
/* --------------------------------------------------------------
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,
fgTIME t)
/*************************************************************************
* 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)
{
struct CelestialCoord
geocCoord, topocCoord;
string tpath, fg_tpath;
int width, height;
double
fgPrintf( FG_GENERAL, FG_INFO, "Initializing Moon Texture\n");
#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);
// load in the texture data
tpath = current_options.get_fg_root() + "/Textures/" + "moon.rgb";
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 )
{
fgPrintf( FG_GENERAL, FG_EXIT,
"Error in loading moon texture %s\n", 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;
fgAIRCRAFT *air;
fgFLIGHT *f;
a = &current_aircraft;
f = a->flight;
/* calculate the angle between ecliptic and equatorial coordinate
* system, in Radians */
air = &current_aircraft;
f = air->flight;
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);
// 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
/* 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 ecliptic latitude and longitude here */
lonecl = atan2( yh, xh);
latecl = atan2( zh, sqrt( xh*xh + yh*yh));
// 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 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;
// 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)
);
fgPrintf(FG_GENERAL, FG_INFO, "Running moon update\n");
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));
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! */
// 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
/* 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);
// 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 = FG_Latitude - 0.003358 * 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;
}
void fgMoonInit( void ) {
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);
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);
if (geoRa < 0)
geoRa += (2*FG_PI);
xglPushMatrix ();
xglTranslatef (xMoon, yMoon, zMoon);
// xglScalef (1400, 1400, 1400);
// glutSolidSphere (1.0, 10, 10);
glutSolidSphere (1200.0, 10, 10);
xglPopMatrix ();
xglEndList ();
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);
}
/* Draw the moon */
void fgMoonRender( void ) {
GLfloat moonColor[4] = {0.85, 0.75, 0.35, 1.0};
GLfloat black[4] = { 0.0, 0.0, 0.0, 1.0 };
/************************************************************************
* 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);
xglMaterialfv (GL_FRONT, GL_AMBIENT, black);
xglMaterialfv (GL_FRONT, GL_DIFFUSE, moonColor);
//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);
xglCallList(moon);
fgPrintf( FG_GENERAL, FG_INFO,
"Ra = (%f), Dec= (%f)", (RAD_TO_DEG *ra), (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);
}
/* $Log$
/* Revision 1.6 1998/09/03 21:25:39 curt
/* log file tweak.
/*
* Revision 1.5 1998/07/30 23:43:30 curt
* Eliminated glScale call so that glutSolidSphere normals are preserved
* correctly. Also made the sun & moon a bit smaller.
*
* Revision 1.4 1998/04/28 01:18:59 curt
* Type-ified fgTIME and fgVIEW
*
* Revision 1.3 1998/04/25 22:06:24 curt
* Edited cvs log messages in source files ... bad bad bad!
*
* Revision 1.2 1998/04/24 00:45:00 curt
* Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
* Fixed a bug when generating sky colors.
*
* 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 <pbleisch@acm.org> 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.
*
*/