1 /**************************************************************************
2 * stars.c -- data structures and routines for managing and rendering stars.
4 * Written by Curtis Olson, started August 1997.
6 * Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of the
11 * License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 * (Log is kept at end of this file)
24 **************************************************************************/
41 #include <Aircraft/aircraft.h>
42 #include <Debug/fg_debug.h>
43 #include <Include/fg_constants.h>
44 #include <Include/general.h>
45 #include <Main/views.hxx>
46 #include <Time/fg_time.h>
49 #include "planets.hxx"
53 #define EpochStart (631065600)
54 #define DaysSinceEpoch(secs) (((secs)-EpochStart)*(1.0/(24*3600)))
57 /* Define four structures, each with varying amounts of stars */
58 /* static */ GLint stars[FG_STAR_LEVELS];
61 /* Initialize the Star Management Subsystem */
62 int fgStarsInit( void ) {
65 /* struct CelestialCoord pltPos; */
67 char line[256], name[256];
69 double right_ascension, declination, magnitude;
70 /* double ra_save, decl_save; */
71 /* double ra_save1, decl_save1; */
72 int count, i, max_stars;
74 fgPrintf( FG_ASTRO, FG_INFO, "Initializing stars\n");
78 /* build the full path name to the stars data base file */
80 strcat(path, g->root_dir);
81 strcat(path, "/Scenery/");
82 strcat(path, "Stars.dat");
84 max_stars = FG_MAX_STARS;
86 for ( i = 0; i < FG_STAR_LEVELS; i++ ) {
87 fgPrintf( FG_ASTRO, FG_INFO,
88 " Loading %d Stars: %s\n", max_stars, path);
90 if ( (fd = fopen(path, "r")) == NULL ) {
91 fgPrintf( FG_ASTRO, FG_ALERT,
92 "Cannot open star file: '%s'\n", path);
93 return 0; // Oops, lets not even try to continue. This is critical.
96 stars[i] = xglGenLists(1);
97 xglNewList( stars[i], GL_COMPILE );
98 xglBegin( GL_POINTS );
100 /* read in each line of the file */
102 while ( (fgets(line, 256, fd) != NULL) && (count < max_stars) ) {
105 /* printf(" Read line = %s", front); */
107 /* advance to first non-whitespace character */
108 while ( (front[0] == ' ') || (front[0] == '\t') ) {
112 /* printf(" Line length (after trimming) = %d\n", strlen(front));*/
114 if ( front[0] == '#' ) {
116 } else if ( strlen(front) <= 1 ) {
123 while ( end[0] != ',' ) {
131 sscanf(front, "%lf,%lf,%lf\n",
132 &right_ascension, &declination, &magnitude);
135 if ( strcmp(name, "Betelgeuse") == 0 ) {
136 printf(" *** Marking %s\n", name);
137 ra_save = right_ascension;
138 decl_save = declination;
143 if ( strcmp(name, "Alnilam") == 0 ) {
144 printf(" *** Marking %s\n", name);
145 ra_save1 = right_ascension;
146 decl_save1 = declination;
150 /* scale magnitudes to (0.0 - 1.0) */
151 magnitude = (0.0 - magnitude) / 5.0 + 1.0;
153 /* scale magnitudes again so they look ok */
154 if ( magnitude > 1.0 ) { magnitude = 1.0; }
155 if ( magnitude < 0.0 ) { magnitude = 0.0; }
157 magnitude * 0.7 + (((FG_STAR_LEVELS - 1) - i) * 0.1);
158 /* printf(" Found star: %d %s, %.3f %.3f %.3f\n", count,
159 name, right_ascension, declination, magnitude); */
161 xglColor3f( magnitude, magnitude, magnitude );
162 /*xglColor3f(0,0,0);*/
163 xglVertex3f( 50000.0 * cos(right_ascension) * cos(declination),
164 50000.0 * sin(right_ascension) * cos(declination),
165 50000.0 * sin(declination) );
177 xglBegin(GL_LINE_LOOP);
178 xglColor3f(1.0, 0.0, 0.0);
179 xglVertex3f( 50000.0 * cos(ra_save-0.2) * cos(decl_save-0.2),
180 50000.0 * sin(ra_save-0.2) * cos(decl_save-0.2),
181 50000.0 * sin(decl_save-0.2) );
182 xglVertex3f( 50000.0 * cos(ra_save+0.2) * cos(decl_save-0.2),
183 50000.0 * sin(ra_save+0.2) * cos(decl_save-0.2),
184 50000.0 * sin(decl_save-0.2) );
185 xglVertex3f( 50000.0 * cos(ra_save+0.2) * cos(decl_save+0.2),
186 50000.0 * sin(ra_save+0.2) * cos(decl_save+0.2),
187 50000.0 * sin(decl_save+0.2) );
188 xglVertex3f( 50000.0 * cos(ra_save-0.2) * cos(decl_save+0.2),
189 50000.0 * sin(ra_save-0.2) * cos(decl_save+0.2),
190 50000.0 * sin(decl_save+0.2) );
195 xglBegin(GL_LINE_LOOP);
196 xglColor3f(0.0, 1.0, 0.0);
197 xglVertex3f( 50000.0 * cos(ra_save1-0.2) * cos(decl_save1-0.2),
198 50000.0 * sin(ra_save1-0.2) * cos(decl_save1-0.2),
199 50000.0 * sin(decl_save1-0.2) );
200 xglVertex3f( 50000.0 * cos(ra_save1+0.2) * cos(decl_save1-0.2),
201 50000.0 * sin(ra_save1+0.2) * cos(decl_save1-0.2),
202 50000.0 * sin(decl_save1-0.2) );
203 xglVertex3f( 50000.0 * cos(ra_save1+0.2) * cos(decl_save1+0.2),
204 50000.0 * sin(ra_save1+0.2) * cos(decl_save1+0.2),
205 50000.0 * sin(decl_save1+0.2) );
206 xglVertex3f( 50000.0 * cos(ra_save1-0.2) * cos(decl_save1+0.2),
207 50000.0 * sin(ra_save1-0.2) * cos(decl_save1+0.2),
208 50000.0 * sin(decl_save1+0.2) );
217 return 1; // OK, we got here because initialization worked.
222 void fgStarsRender( void ) {
229 f = current_aircraft.flight;
230 l = &cur_light_params;
231 t = &cur_time_params;
234 /* FG_PI_2 + 0.1 is about 6 degrees after sundown and before sunrise */
236 /* t->sun_angle = 3.0; */ /* to force stars to be drawn (for testing) */
238 /* render the stars */
239 if ( l->sun_angle > (FG_PI_2 + 5 * DEG_TO_RAD ) ) {
240 /* determine which star structure to draw */
241 if ( l->sun_angle > (FG_PI_2 + 7.25 * DEG_TO_RAD ) ) {
243 } else if ( l->sun_angle > (FG_PI_2 + 6.50 * DEG_TO_RAD ) ) {
245 } else if ( l->sun_angle > (FG_PI_2 + 5.75 * DEG_TO_RAD ) ) {
251 /* printf("RENDERING STARS = %d (night)\n", i); */
253 xglCallList(stars[i]);
255 /* printf("not RENDERING STARS (day)\n"); */
261 /* Revision 1.1 1998/04/22 13:21:34 curt
262 /* C++ - ifing the code a bit.
264 * Revision 1.11 1998/04/18 04:13:58 curt
265 * Moved fg_debug.c to it's own library.
267 * Revision 1.10 1998/04/03 21:52:51 curt
268 * Converting to Gnu autoconf system.
270 * Revision 1.9 1998/03/14 00:27:12 curt
271 * Updated fgGENERAL to a "type" of struct.
273 * Revision 1.8 1998/02/12 21:59:38 curt
274 * Incorporated code changes contributed by Charlie Hotchkiss
275 * <chotchkiss@namg.us.anritsu.com>
277 * Revision 1.7 1998/02/09 15:07:48 curt
280 * Revision 1.6 1998/02/02 20:53:23 curt
283 * Revision 1.5 1998/01/27 18:35:53 curt
286 * Revision 1.4 1998/01/27 00:47:49 curt
287 * Incorporated Paul Bleisch's <bleisch@chromatic.com> new debug message
288 * system and commandline/config file processing code.
290 * Revision 1.3 1998/01/19 19:26:59 curt
291 * Merged in make system changes from Bob Kuehne <rpk@sgi.com>
292 * This should simplify things tremendously.
294 * Revision 1.2 1998/01/19 18:40:18 curt
295 * Tons of little changes to clean up the code and to remove fatal errors
296 * when building with the c++ compiler.
298 * Revision 1.1 1998/01/07 03:16:20 curt
299 * Moved from .../Src/Scenery/ to .../Src/Astro/
301 * Revision 1.24 1997/12/30 22:22:39 curt
302 * Further integration of event manager.
304 * Revision 1.23 1997/12/30 20:47:53 curt
305 * Integrated new event manager with subsystem initializations.
307 * Revision 1.22 1997/12/30 16:36:53 curt
308 * Merged in Durk's changes ...
310 * Revision 1.21 1997/12/19 23:35:00 curt
311 * Lot's of tweaking with sky rendering and lighting.
313 * Revision 1.20 1997/12/15 23:55:03 curt
314 * Add xgl wrappers for debugging.
315 * Generate terrain normals on the fly.
317 * Revision 1.19 1997/12/12 19:53:00 curt
318 * Working on lightling and material properties.
320 * Revision 1.18 1997/12/10 22:37:52 curt
321 * Prepended "fg" on the name of all global structures that didn't have it yet.
322 * i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
324 * Revision 1.17 1997/12/09 04:25:33 curt
325 * Working on adding a global lighting params structure.
327 * Revision 1.16 1997/11/25 19:25:38 curt
328 * Changes to integrate Durk's moon/sun code updates + clean up.
330 * Revision 1.15 1997/10/30 12:38:45 curt
331 * Working on new scenery subsystem.
333 * Revision 1.14 1997/10/28 21:00:22 curt
334 * Changing to new terrain format.
336 * Revision 1.13 1997/10/25 03:18:28 curt
337 * Incorporated sun, moon, and planet position and rendering code contributed
340 * Revision 1.12 1997/09/23 00:29:43 curt
341 * Tweaks to get things to compile with gcc-win32.
343 * Revision 1.11 1997/09/22 14:44:21 curt
344 * Continuing to try to align stars correctly.
346 * Revision 1.10 1997/09/20 03:34:32 curt
347 * Still trying to get those durned stars aligned properly.
349 * Revision 1.9 1997/09/18 16:20:09 curt
350 * At dusk/dawn add/remove stars in stages.
352 * Revision 1.8 1997/09/16 22:14:52 curt
353 * Tweaked time of day lighting equations. Don't draw stars during the day.
355 * Revision 1.7 1997/09/16 15:50:31 curt
356 * Working on star alignment and time issues.
358 * Revision 1.6 1997/09/05 14:17:31 curt
359 * More tweaking with stars.
361 * Revision 1.5 1997/09/05 01:35:59 curt
362 * Working on getting stars right.
364 * Revision 1.4 1997/09/04 02:17:38 curt
367 * Revision 1.3 1997/08/29 17:55:28 curt
368 * Worked on properly aligning the stars.
370 * Revision 1.2 1997/08/27 21:32:30 curt
371 * Restructured view calculation code. Added stars.
373 * Revision 1.1 1997/08/27 03:34:48 curt