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Incorporated Durk's Astro/ tweaks. Includes unifying the sun position

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calculation code between sun display, and other FG sections that use this
for things like lighting.
This commit is contained in:
curt
2009-09-15 18:31:29 +02:00
committed by Tim Moore
parent 3e386f51a1
commit 20cf326fec
7 changed files with 186 additions and 210 deletions
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Astro/sun.c
+35 -50
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@@ -25,26 +25,23 @@
#include <GL/glut.h>
#include <XGL/xgl.h>
#include <Time/fg_time.h>
#include <Main/views.h>
#include <Astro/orbits.h>
#include <Astro/sun.h>
#include <Main/fg_debug.h>
#include <Include/fg_constants.h>
#include <Main/fg_debug.h>
#include <Main/views.h>
#include <Time/fg_time.h>
#include <Time/sunpos.h>
GLint sun_obj = 0;
static struct CelestialCoord sunPos;
float xSun, ySun, zSun;
fgSUNPOS solarPosition;
struct SunPos fgCalcSunPos(struct OrbElements params)
void fgCalcSunPos(struct OrbElements params)
{
double
EccAnom, lonSun,
xv, yv, v, r;
struct SunPos
solarPosition;
double EccAnom, xv, yv, v, r;
/* calculate the eccentric anomaly */
EccAnom = fgCalcEccAnom(params.M, params.e);
@@ -56,37 +53,31 @@ struct SunPos fgCalcSunPos(struct OrbElements params)
r = sqrt(xv*xv + yv*yv);
/* calculate the the Sun's true longitude (lonsun) */
lonSun = v + params.w;
solarPosition.lonSun = v + params.w;
/* convert true longitude and distance to ecliptic rectangular geocentric
coordinates (xs, ys) */
solarPosition.xs = r * cos(lonSun);
solarPosition.ys = r * sin(lonSun);
/* convert true longitude and distance to ecliptic rectangular
geocentric coordinates (xs, ys) */
solarPosition.xs = r * cos (solarPosition.lonSun);
solarPosition.ys = r * sin (solarPosition.lonSun);
solarPosition.dist = r;
return solarPosition;
/* return solarPosition; */
}
struct CelestialCoord fgCalculateSun(struct OrbElements params, struct fgTIME t)
{
struct CelestialCoord
result;
struct SunPos
SolarPosition;
double
xe, ye, ze, ecl, actTime;
struct CelestialCoord result;
double xe, ye, ze, ecl, actTime;
/* calculate the angle between ecliptic and equatorial coordinate system */
actTime = fgCalcActTime(t);
ecl = DEG_TO_RAD * (23.4393 - 3.563E-7 * actTime); // Angle now in Rads
ecl = DEG_TO_RAD * (23.4393 - 3.563E-7 * actTime); // Angle now in Rads
/* calculate the sun's ecliptic position */
SolarPosition = fgCalcSunPos(params);
/* convert ecliptic coordinates to equatorial rectangular geocentric coordinates */
xe = SolarPosition.xs;
ye = SolarPosition.ys * cos(ecl);
ze = SolarPosition.ys * sin(ecl);
/* convert ecliptic coordinates to equatorial rectangular
geocentric coordinates */
xe = solarPosition.xs;
ye = solarPosition.ys * cos (ecl);
ze = solarPosition.ys * sin (ecl);
/* and finally... Calulate Right Ascention and Declination */
result.RightAscension = atan2( ye, xe);
@@ -100,6 +91,7 @@ void fgSunInit( void ) {
struct fgLIGHT *l;
struct fgTIME *t;
struct fgVIEW *v;
float xSun, ySun, zSun;
/* GLfloat color[4] = { 1.00, 1.00, 1.00, 1.00 }; */
double x_2, x_4, x_8, x_10;
@@ -112,9 +104,14 @@ void fgSunInit( void ) {
fgPrintf( FG_ASTRO, FG_INFO, " Initializing the Sun\n");
// Calculate basic sun position
fgSolarSystemUpdate(&(pltOrbElements[0]), cur_time_params);
sunPos = fgCalculateSun(pltOrbElements[0], cur_time_params);
// Calculate additional sun position parameters based on the above
// position that are needed by other parts of FG
fgUpdateSunPos();
fgPrintf( FG_ASTRO, FG_INFO,
"Sun found at %f (ra), %f (dec)\n",
sunPos.RightAscension, sunPos.Declination);
@@ -162,29 +159,12 @@ void fgSunInit( void ) {
"Sun Angle : %f\n" ,
amb[0], amb[1], amb[2], ambient, l->sun_angle);
/* set lighting parameters */
/*xglLightfv(GL_LIGHT0, GL_AMBIENT, color );
xglLightfv(GL_LIGHT0, GL_DIFFUSE, color );
xglMaterialfv(GL_FRONT, GL_AMBIENT, amb);
xglMaterialfv(GL_FRONT, GL_DIFFUSE, diff);
xglMaterialfv(GL_FRONT, GL_SHININESS, diff);
xglMaterialfv(GL_FRONT, GL_EMISSION, diff);
xglMaterialfv(GL_FRONT, GL_SPECULAR, diff); */
/* xglDisable( GL_LIGHTING ); */
xglPushMatrix();
xglTranslatef(xSun, ySun, zSun);
xglScalef(1400, 1400, 1400);
/*xglColor3f(0.85, 0.65, 0.05);*/
xglColor3f(amb[0], amb[1], amb[2]);
glutSolidSphere(1.0, 10, 10);
xglPopMatrix();
/* xglEnable( GL_LIGHTING ); */
xglEndList();
}
@@ -196,10 +176,15 @@ void fgSunRender( void ) {
/* $Log$
/* Revision 1.6 1998/02/12 21:59:39 curt
/* Incorporated code changes contributed by Charlie Hotchkiss
/* <chotchkiss@namg.us.anritsu.com>
/* Revision 1.7 1998/02/23 19:07:56 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 1998/02/12 21:59:39 curt
* Incorporated code changes contributed by Charlie Hotchkiss
* <chotchkiss@namg.us.anritsu.com>
*
* Revision 1.5 1998/02/02 20:53:24 curt
* To version 0.29
*