/************************************************************************** * 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 WIN32 # include #endif #include #include #include #include #include #include "stars.h" #include "../constants.h" #include "../general.h" #include "../GLUT/views.h" #include "../Aircraft/aircraft.h" #define EpochStart (631065600) #define DaysSinceEpoch(secs) (((secs)-EpochStart)*(1.0/(24*3600))) static GLint stars; /* Initialize the Star Management Subsystem */ void fgStarsInit() { FILE *fd; struct GENERAL *g; char path[1024]; char line[256], name[256]; char *front, *end; double right_ascension, declination, magnitude; double ra_save, decl_save; double ra_save1, decl_save1; double ra_save2, decl_save2; GLfloat mag[4] = {0.0, 0.0, 0.0, 1.0}; int count; g = &general; /* build the full path name to the stars data base file */ path[0] = '\0'; strcat(path, g->root_dir); strcat(path, "/Scenery/"); strcat(path, "Stars.dat"); printf("Loading Stars: %s\n", path); if ( (fd = fopen(path, "r")) == NULL ) { printf("Cannot open star file: '%s'\n", path); return; } stars = glGenLists(1); glNewList( stars, GL_COMPILE ); glBegin( GL_POINTS ); /* read in each line of the file */ count = 0; while ( (fgets(line, 256, fd) != NULL) && (count < 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); if ( strcmp(name, "Deneb") == 0 ) { printf("\n*** Marking %s\n\n", name); ra_save = right_ascension; decl_save = declination; } if ( strcmp(name, "Alderamin") == 0 ) { printf("\n*** Marking %s\n\n", name); ra_save1 = right_ascension; decl_save1 = declination; } /* scale magnitudes to (0.0 - 1.0) */ magnitude = (-1.46 - magnitude) / 10.0 + 1.0; /* scale magnitudes again so they look ok */ magnitude = magnitude * 0.8 + 0.2; mag[0] = mag[1] = mag[2] = magnitude; printf("Found star: %d %s, %.3f %.3f %.3f\n", count, name, right_ascension, declination, magnitude); glColor3f( mag[0], mag[1], mag[2] ); glVertex3f( 190000.0 * sin(right_ascension) * cos(declination), 190000.0 * cos(right_ascension) * cos(declination), 190000.0 * sin(declination) ); count++; } /* if valid line */ } /* while */ fclose(fd); glEnd(); glBegin(GL_LINE_LOOP); glColor3f(1.0, 0.0, 0.0); glVertex3f( 190000.0 * sin(ra_save-0.2) * cos(decl_save-0.2), 190000.0 * cos(ra_save-0.2) * cos(decl_save-0.2), 190000.0 * sin(decl_save-0.2) ); glVertex3f( 190000.0 * sin(ra_save+0.2) * cos(decl_save-0.2), 190000.0 * cos(ra_save+0.2) * cos(decl_save-0.2), 190000.0 * sin(decl_save-0.2) ); glVertex3f( 190000.0 * sin(ra_save+0.2) * cos(decl_save+0.2), 190000.0 * cos(ra_save+0.2) * cos(decl_save+0.2), 190000.0 * sin(decl_save+0.2) ); glVertex3f( 190000.0 * sin(ra_save-0.2) * cos(decl_save+0.2), 190000.0 * cos(ra_save-0.2) * cos(decl_save+0.2), 190000.0 * sin(decl_save+0.2) ); glEnd(); glBegin(GL_LINE_LOOP); glColor3f(0.0, 1.0, 0.0); glVertex3f( 190000.0 * sin(ra_save1-0.2) * cos(decl_save1-0.2), 190000.0 * cos(ra_save1-0.2) * cos(decl_save1-0.2), 190000.0 * sin(decl_save1-0.2) ); glVertex3f( 190000.0 * sin(ra_save1+0.2) * cos(decl_save1-0.2), 190000.0 * cos(ra_save1+0.2) * cos(decl_save1-0.2), 190000.0 * sin(decl_save1-0.2) ); glVertex3f( 190000.0 * sin(ra_save1+0.2) * cos(decl_save1+0.2), 190000.0 * cos(ra_save1+0.2) * cos(decl_save1+0.2), 190000.0 * sin(decl_save1+0.2) ); glVertex3f( 190000.0 * sin(ra_save1-0.2) * cos(decl_save1+0.2), 190000.0 * cos(ra_save1-0.2) * cos(decl_save1+0.2), 190000.0 * sin(decl_save1+0.2) ); glEnd(); glEndList(); } /* Draw the Stars */ void fgStarsRender() { struct FLIGHT *f; struct VIEW *v; double angle; f = ¤t_aircraft.flight; v = ¤t_view; printf("RENDERING STARS\n"); glDisable( GL_FOG ); glDisable( GL_LIGHTING ); glPushMatrix(); glTranslatef( v->view_pos.x, v->view_pos.y, v->view_pos.z ); angle = FG_2PI * fmod(DaysSinceEpoch(time(NULL)), 1.0); glRotatef( -angle * RAD_TO_DEG, 0.0, 0.0, 1.0 ); printf("Rotating stars by %.2f\n", -angle * RAD_TO_DEG); glCallList(stars); glPopMatrix(); glEnable( GL_LIGHTING ); glEnable( GL_FOG ); } /* $Log$ /* 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. * */