simgear/Scenery/astro.c

131 lines
3.2 KiB
C

/**************************************************************************
* astro.c
*
* Written by Durk Talsma. Started November 1997, for use with the flight
* gear project.
*
* 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 <math.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <GL/glut.h>
#include "astro.h"
#include "moon.h"
#include "orbits.h"
#include "planets.h"
#include "stars.h"
#include "sun.h"
#include "../constants.h"
#include "../general.h"
#include "../Main/views.h"
#include "../Aircraft/aircraft.h"
#include "../Time/fg_time.h"
static double prevUpdate = 0;
/* Initialize Astronomical Objects */
void fgAstroInit() {
struct fgTIME *t;
t = &cur_time_params;
/* Initialize the orbital elements of sun, moon and mayor planets */
fgSolarSystemInit(*t);
/* Intialize the moon's position */
fgMoonInit();
/* Initialize the sun's position */
fgSunInit();
/* Initialize the Stars subsystem */
fgStarsInit();
}
/* Render Astronomical Objects */
void fgAstroRender() {
struct FLIGHT *f;
struct fgLIGHT *l;
struct VIEW *v;
struct fgTIME *t;
double angle;
f = &current_aircraft.flight;
l = &cur_light_params;
t = &cur_time_params;
v = &current_view;
/* a hack: Force sun and moon position to be updated on an hourly basis */
if (((t->gst - prevUpdate) > 1) || (t->gst < prevUpdate)) {
prevUpdate = t->gst;
fgSunInit();
fgMoonInit();
}
/* Disable fog effects */
glDisable( GL_FOG );
/* reverse light direction so the moon is displayed properly */
glLightfv( GL_LIGHT0, GL_POSITION, l->sun_vec_inv );
glPushMatrix();
/* Translate to view position */
glTranslatef( v->view_pos.x, v->view_pos.y, v->view_pos.z );
/* Rotate based on gst (side real time) */
angle = t->gst * 15.041085; /* should be 15.041085, Curt thought it was 15*/
#ifdef DEBUG
printf("Rotating astro objects by %.2f degrees\n",angle);
#endif
glRotatef( angle, 0.0, 0.0, -1.0 );
/* render the stars */
fgStarsRender();
/* render the moon */
fgMoonRender();
/* render the sun */
fgSunRender();
glPopMatrix();
/* reenable fog effects */
glEnable( GL_FOG );
}
/* $Log$
/* Revision 1.2 1997/12/09 04:25:33 curt
/* Working on adding a global lighting params structure.
/*
* Revision 1.1 1997/11/25 23:20:22 curt
* Initial revision.
*
*/