/************************************************************************** * stars.c -- data structures and routines for managing and rendering stars. * * Written by Curtis Olson, started August 1997. * * Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com * * 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) **************************************************************************/ #ifdef HAVE_CONFIG_H # include <config.h> #endif #ifdef HAVE_WINDOWS_H # include <windows.h> #endif #include <math.h> #include <stdio.h> #include <string.h> #include <time.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/fg_types.h> #include <Include/fg_zlib.h> #include <Main/options.hxx> #include <Main/views.hxx> #include <Time/fg_time.hxx> #include "orbits.hxx" #include "planets.hxx" #include "stars.hxx" #define EpochStart (631065600) #define DaysSinceEpoch(secs) (((secs)-EpochStart)*(1.0/(24*3600))) #define FG_MAX_STARS 3500 /* Define four structures, each with varying amounts of stars */ static GLint stars[FG_STAR_LEVELS]; /* Initialize the Star Management Subsystem */ int fgStarsInit( void ) { fgPoint3d starlist[FG_MAX_STARS]; fgFile fd; /* struct CelestialCoord pltPos; */ char path[256], gzpath[256]; char line[256], name[256]; char *front, *end; double right_ascension, declination, magnitude; double min_magnitude[FG_STAR_LEVELS]; /* double ra_save, decl_save; */ /* double ra_save1, decl_save1; */ int i, j, starcount, count; fgPrintf( FG_ASTRO, FG_INFO, "Initializing stars\n"); /* build the full path name to the stars data base file */ current_options.get_fg_root(path); strcat(path, "/Scenery/"); strcat(path, "Stars"); if ( FG_STAR_LEVELS < 4 ) { fgPrintf( FG_ASTRO, FG_EXIT, "Big whups in stars.cxx\n"); } fgPrintf( FG_ASTRO, FG_INFO, " Loading stars from %s\n", path); // load star data file if ( (fd = fgopen(path, "rb")) == NULL ) { strcpy(gzpath, path); strcat(gzpath, ".gz"); if ( (fd = fgopen(gzpath, "rb")) == NULL ) { // Oops, lets not even try to continue. This is critical. fgPrintf( FG_ASTRO, FG_EXIT, "Cannot open star file: '%s'\n", path); } } starcount = 0; // read in each line of the file while ( (fggets(fd, line, 256) != NULL) && (starcount < FG_MAX_STARS) ) { front = line; // printf(" Read line = %s", front); // advance to first non-whitespace character while ( (front[0] == ' ') || (front[0] == '\t') ) { front++; } // printf(" Line length (after trimming) = %d\n", strlen(front)); if ( front[0] == '#' ) { // comment } else if ( strlen(front) <= 1 ) { // blank line } else { // star data line // get name end = front; while ( end[0] != ',' ) { end++; } end[0] = '\0'; strcpy(name, front); front = end; front++; sscanf(front, "%lf,%lf,%lf\n", &right_ascension, &declination, &magnitude); starlist[starcount].x = right_ascension; starlist[starcount].y = declination; starlist[starcount].z = magnitude; starcount++; } } min_magnitude[0] = 4.2; min_magnitude[1] = 3.6; min_magnitude[2] = 3.0; min_magnitude[3] = 2.4; min_magnitude[4] = 1.8; min_magnitude[5] = 1.2; min_magnitude[6] = 0.6; min_magnitude[7] = 0.0; // build the various star display lists for ( i = 0; i < FG_STAR_LEVELS; i++ ) { stars[i] = xglGenLists(1); xglNewList( stars[i], GL_COMPILE ); xglBegin( GL_POINTS ); count = 0; for ( j = 0; j < starcount; j++ ) { magnitude = starlist[j].z; // printf("magnitude = %.2f\n", magnitude); if ( magnitude < min_magnitude[i] ) { right_ascension = starlist[j].x; declination = starlist[j].y; count++; /* scale magnitudes to (0.0 - 1.0) */ magnitude = (0.0 - magnitude) / 5.0 + 1.0; /* scale magnitudes again so they look ok */ if ( magnitude > 1.0 ) { magnitude = 1.0; } if ( magnitude < 0.0 ) { magnitude = 0.0; } /* magnitude = magnitude * 0.7 + (((FG_STAR_LEVELS - 1) - i) * 0.042); */ magnitude = magnitude * 0.9 + (((FG_STAR_LEVELS - 1) - i) * 0.014); /* printf(" Found star: %d %s, %.3f %.3f %.3f\n", count, name, right_ascension, declination, magnitude); */ xglColor3f( magnitude, magnitude, magnitude ); /*xglColor3f(0,0,0);*/ xglVertex3f( 50000.0*cos(right_ascension)*cos(declination), 50000.0*sin(right_ascension)*cos(declination), 50000.0*sin(declination) ); } } /* while */ xglEnd(); /* xglBegin(GL_LINE_LOOP); xglColor3f(1.0, 0.0, 0.0); xglVertex3f( 50000.0 * cos(ra_save-0.2) * cos(decl_save-0.2), 50000.0 * sin(ra_save-0.2) * cos(decl_save-0.2), 50000.0 * sin(decl_save-0.2) ); xglVertex3f( 50000.0 * cos(ra_save+0.2) * cos(decl_save-0.2), 50000.0 * sin(ra_save+0.2) * cos(decl_save-0.2), 50000.0 * sin(decl_save-0.2) ); xglVertex3f( 50000.0 * cos(ra_save+0.2) * cos(decl_save+0.2), 50000.0 * sin(ra_save+0.2) * cos(decl_save+0.2), 50000.0 * sin(decl_save+0.2) ); xglVertex3f( 50000.0 * cos(ra_save-0.2) * cos(decl_save+0.2), 50000.0 * sin(ra_save-0.2) * cos(decl_save+0.2), 50000.0 * sin(decl_save+0.2) ); xglEnd(); */ /* xglBegin(GL_LINE_LOOP); xglColor3f(0.0, 1.0, 0.0); xglVertex3f( 50000.0 * cos(ra_save1-0.2) * cos(decl_save1-0.2), 50000.0 * sin(ra_save1-0.2) * cos(decl_save1-0.2), 50000.0 * sin(decl_save1-0.2) ); xglVertex3f( 50000.0 * cos(ra_save1+0.2) * cos(decl_save1-0.2), 50000.0 * sin(ra_save1+0.2) * cos(decl_save1-0.2), 50000.0 * sin(decl_save1-0.2) ); xglVertex3f( 50000.0 * cos(ra_save1+0.2) * cos(decl_save1+0.2), 50000.0 * sin(ra_save1+0.2) * cos(decl_save1+0.2), 50000.0 * sin(decl_save1+0.2) ); xglVertex3f( 50000.0 * cos(ra_save1-0.2) * cos(decl_save1+0.2), 50000.0 * sin(ra_save1-0.2) * cos(decl_save1+0.2), 50000.0 * sin(decl_save1+0.2) ); xglEnd(); */ xglEndList(); fgPrintf( FG_ASTRO, FG_INFO, " Loading %d stars brighter than %.2f\n", count, min_magnitude[i]); } return 1; // OK, we got here because initialization worked. } /* Draw the Stars */ void fgStarsRender( void ) { fgFLIGHT *f; fgVIEW *v; fgLIGHT *l; fgTIME *t; int i; f = current_aircraft.flight; l = &cur_light_params; t = &cur_time_params; v = ¤t_view; /* FG_PI_2 + 0.1 is about 6 degrees after sundown and before sunrise */ /* t->sun_angle = 3.0; */ /* to force stars to be drawn (for testing) */ /* render the stars */ if ( l->sun_angle > (FG_PI_2 + 5 * DEG_TO_RAD ) ) { /* determine which star structure to draw */ if ( l->sun_angle > (FG_PI_2 + 10.0 * DEG_TO_RAD ) ) { i = 0; } else if ( l->sun_angle > (FG_PI_2 + 8.8 * DEG_TO_RAD ) ) { i = 1; } else if ( l->sun_angle > (FG_PI_2 + 7.5 * DEG_TO_RAD ) ) { i = 2; } else if ( l->sun_angle > (FG_PI_2 + 7.0 * DEG_TO_RAD ) ) { i = 3; } else if ( l->sun_angle > (FG_PI_2 + 6.5 * DEG_TO_RAD ) ) { i = 4; } else if ( l->sun_angle > (FG_PI_2 + 6.0 * DEG_TO_RAD ) ) { i = 5; } else if ( l->sun_angle > (FG_PI_2 + 5.5 * DEG_TO_RAD ) ) { i = 6; } else { i = 7; } /* printf("RENDERING STARS = %d (night)\n", i); */ xglCallList(stars[i]); } else { /* printf("not RENDERING STARS (day)\n"); */ } } /* $Log$ /* Revision 1.10 1998/08/10 20:33:09 curt /* Rewrote star loading and rendering to: /* 1. significantly improve load speed /* 2. transition from no stars to stars through eight stages. /* * Revision 1.9 1998/08/06 12:45:20 curt * Modified to bring in stars in 8 increments based on magnitude, not number * of stars. * * Revision 1.8 1998/07/13 21:00:10 curt * Wrote access functions for current fgOPTIONS. * * Revision 1.7 1998/05/29 20:35:42 curt * Added zlib support for reading in compressed data files. * * Revision 1.6 1998/05/13 18:25:35 curt * Root path info moved to fgOPTIONS. * * Revision 1.5 1998/04/28 01:19:03 curt * Type-ified fgTIME and fgVIEW * * Revision 1.4 1998/04/26 05:10:02 curt * "struct fgLIGHT" -> "fgLIGHT" because fgLIGHT is typedef'd. * * Revision 1.3 1998/04/25 22:06:26 curt * Edited cvs log messages in source files ... bad bad bad! * * Revision 1.2 1998/04/24 00:45:03 curt * Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H" * Fixed a bug when generating sky colors. * * Revision 1.1 1998/04/22 13:21:34 curt * C++ - ifing the code a bit. * * Revision 1.11 1998/04/18 04:13:58 curt * Moved fg_debug.c to it's own library. * * Revision 1.10 1998/04/03 21:52:51 curt * Converting to Gnu autoconf system. * * Revision 1.9 1998/03/14 00:27:12 curt * Updated fgGENERAL to a "type" of struct. * * Revision 1.8 1998/02/12 21:59:38 curt * Incorporated code changes contributed by Charlie Hotchkiss * <chotchkiss@namg.us.anritsu.com> * * Revision 1.7 1998/02/09 15:07:48 curt * Minor tweaks. * * Revision 1.6 1998/02/02 20:53:23 curt * To version 0.29 * * Revision 1.5 1998/01/27 18:35:53 curt * Minor tweaks. * * Revision 1.4 1998/01/27 00:47:49 curt * Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message * system and commandline/config file processing code. * * Revision 1.3 1998/01/19 19:26:59 curt * Merged in make system changes from Bob Kuehne <rpk@sgi.com> * This should simplify things tremendously. * * Revision 1.2 1998/01/19 18:40:18 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 03:16:20 curt * Moved from .../Src/Scenery/ to .../Src/Astro/ * * Revision 1.24 1997/12/30 22:22:39 curt * Further integration of event manager. * * Revision 1.23 1997/12/30 20:47:53 curt * Integrated new event manager with subsystem initializations. * * Revision 1.22 1997/12/30 16:36:53 curt * Merged in Durk's changes ... * * Revision 1.21 1997/12/19 23:35:00 curt * Lot's of tweaking with sky rendering and lighting. * * Revision 1.20 1997/12/15 23:55:03 curt * Add xgl wrappers for debugging. * Generate terrain normals on the fly. * * Revision 1.19 1997/12/12 19:53:00 curt * Working on lightling and material properties. * * Revision 1.18 1997/12/10 22:37:52 curt * Prepended "fg" on the name of all global structures that didn't have it yet. * i.e. "struct WEATHER {}" became "struct fgWEATHER {}" * * Revision 1.17 1997/12/09 04:25:33 curt * Working on adding a global lighting params structure. * * Revision 1.16 1997/11/25 19:25:38 curt * Changes to integrate Durk's moon/sun code updates + clean up. * * Revision 1.15 1997/10/30 12:38:45 curt * Working on new scenery subsystem. * * Revision 1.14 1997/10/28 21:00:22 curt * Changing to new terrain format. * * Revision 1.13 1997/10/25 03:18:28 curt * Incorporated sun, moon, and planet position and rendering code contributed * by Durk Talsma. * * Revision 1.12 1997/09/23 00:29:43 curt * Tweaks to get things to compile with gcc-win32. * * Revision 1.11 1997/09/22 14:44:21 curt * Continuing to try to align stars correctly. * * Revision 1.10 1997/09/20 03:34:32 curt * Still trying to get those durned stars aligned properly. * * Revision 1.9 1997/09/18 16:20:09 curt * At dusk/dawn add/remove stars in stages. * * Revision 1.8 1997/09/16 22:14:52 curt * Tweaked time of day lighting equations. Don't draw stars during the day. * * Revision 1.7 1997/09/16 15:50:31 curt * Working on star alignment and time issues. * * Revision 1.6 1997/09/05 14:17:31 curt * More tweaking with stars. * * Revision 1.5 1997/09/05 01:35:59 curt * Working on getting stars right. * * Revision 1.4 1997/09/04 02:17:38 curt * Shufflin' stuff. * * Revision 1.3 1997/08/29 17:55:28 curt * Worked on properly aligning the stars. * * Revision 1.2 1997/08/27 21:32:30 curt * Restructured view calculation code. Added stars. * * Revision 1.1 1997/08/27 03:34:48 curt * Initial revision. * */