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Rewrote star loading and rendering to:

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1. significantly improve load speed
  2. transition from no stars to stars through eight stages.
This commit is contained in:
curt 1998-08-10 20:33:09 +00:00
parent 5e9a45af0c
commit 9568e79ac5
1 changed files with 99 additions and 89 deletions
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188
Astro/stars.cxx
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@ -43,6 +43,7 @@
#include <Aircraft/aircraft.h> #include <Aircraft/aircraft.h>
#include <Debug/fg_debug.h> #include <Debug/fg_debug.h>
#include <Include/fg_constants.h> #include <Include/fg_constants.h>
#include <Include/fg_types.h>
#include <Include/fg_zlib.h> #include <Include/fg_zlib.h>
#include <Main/options.hxx> #include <Main/options.hxx>
#include <Main/views.hxx> #include <Main/views.hxx>
@ -55,14 +56,15 @@
#define EpochStart (631065600) #define EpochStart (631065600)
#define DaysSinceEpoch(secs) (((secs)-EpochStart)*(1.0/(24*3600))) #define DaysSinceEpoch(secs) (((secs)-EpochStart)*(1.0/(24*3600)))
#define FG_MAX_STARS 3500
/* Define four structures, each with varying amounts of stars */ /* Define four structures, each with varying amounts of stars */
/* static */ GLint stars[FG_STAR_LEVELS]; static GLint stars[FG_STAR_LEVELS];
/* Initialize the Star Management Subsystem */ /* Initialize the Star Management Subsystem */
int fgStarsInit( void ) { int fgStarsInit( void ) {
fgPoint3d starlist[FG_MAX_STARS];
fgFile fd; fgFile fd;
/* struct CelestialCoord pltPos; */ /* struct CelestialCoord pltPos; */
char path[256], gzpath[256]; char path[256], gzpath[256];
@ -72,7 +74,7 @@ int fgStarsInit( void ) {
double min_magnitude[FG_STAR_LEVELS]; double min_magnitude[FG_STAR_LEVELS];
/* double ra_save, decl_save; */ /* double ra_save, decl_save; */
/* double ra_save1, decl_save1; */ /* double ra_save1, decl_save1; */
int i; int i, j, starcount, count;
fgPrintf( FG_ASTRO, FG_INFO, "Initializing stars\n"); fgPrintf( FG_ASTRO, FG_INFO, "Initializing stars\n");
@ -85,6 +87,60 @@ int fgStarsInit( void ) {
fgPrintf( FG_ASTRO, FG_EXIT, "Big whups in stars.cxx\n"); 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[0] = 4.2;
min_magnitude[1] = 3.6; min_magnitude[1] = 3.6;
min_magnitude[2] = 3.0; min_magnitude[2] = 3.0;
@ -94,102 +150,47 @@ int fgStarsInit( void ) {
min_magnitude[6] = 0.6; min_magnitude[6] = 0.6;
min_magnitude[7] = 0.0; min_magnitude[7] = 0.0;
// build the various star display lists
for ( i = 0; i < FG_STAR_LEVELS; i++ ) { for ( i = 0; i < FG_STAR_LEVELS; i++ ) {
fgPrintf( FG_ASTRO, FG_INFO,
" Loading stars brighter than %.2f from %2\n",
min_magnitude[i], path);
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);
}
}
stars[i] = xglGenLists(1); stars[i] = xglGenLists(1);
xglNewList( stars[i], GL_COMPILE ); xglNewList( stars[i], GL_COMPILE );
xglBegin( GL_POINTS ); xglBegin( GL_POINTS );
/* read in each line of the file */ count = 0;
while ( fggets(fd, line, 256) != NULL ) {
front = line;
/* printf(" Read line = %s", front); */ for ( j = 0; j < starcount; j++ ) {
magnitude = starlist[j].z;
// printf("magnitude = %.2f\n", magnitude);
/* advance to first non-whitespace character */ if ( magnitude < min_magnitude[i] ) {
while ( (front[0] == ' ') || (front[0] == '\t') ) { right_ascension = starlist[j].x;
front++; declination = starlist[j].y;
}
/* printf(" Line length (after trimming) = %d\n", strlen(front));*/ count++;
if ( front[0] == '#' ) { /* scale magnitudes to (0.0 - 1.0) */
/* comment */ magnitude = (0.0 - magnitude) / 5.0 + 1.0;
} else if ( strlen(front) <= 1 ) {
/* blank line */ /* scale magnitudes again so they look ok */
} else { if ( magnitude > 1.0 ) { magnitude = 1.0; }
/* star data line */ if ( magnitude < 0.0 ) { magnitude = 0.0; }
/* magnitude =
/* get name */ magnitude * 0.7 + (((FG_STAR_LEVELS - 1) - i) * 0.042);
end = front; */
while ( end[0] != ',' ) { magnitude = magnitude * 0.9 +
end++; (((FG_STAR_LEVELS - 1) - i) * 0.014);
} /* printf(" Found star: %d %s, %.3f %.3f %.3f\n", count,
end[0] = '\0'; name, right_ascension, declination, magnitude); */
strcpy(name, front);
front = end;
front++;
sscanf(front, "%lf,%lf,%lf\n",
&right_ascension, &declination, &magnitude);
/*
if ( strcmp(name, "Betelgeuse") == 0 ) {
printf(" *** Marking %s\n", name);
ra_save = right_ascension;
decl_save = declination;
}
*/
/*
if ( strcmp(name, "Alnilam") == 0 ) {
printf(" *** Marking %s\n", name);
ra_save1 = right_ascension;
decl_save1 = declination;
}
*/
if ( magnitude < min_magnitude[i] ) {
/* 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( magnitude, magnitude, magnitude );
/*xglColor3f(0,0,0);*/ /*xglColor3f(0,0,0);*/
xglVertex3f( 50000.0*cos(right_ascension)*cos(declination), xglVertex3f( 50000.0*cos(right_ascension)*cos(declination),
50000.0*sin(right_ascension)*cos(declination), 50000.0*sin(right_ascension)*cos(declination),
50000.0*sin(declination) ); 50000.0*sin(declination) );
} }
} // valid line
} /* while */ } /* while */
fgclose(fd);
xglEnd(); xglEnd();
/* /*
@ -229,6 +230,10 @@ int fgStarsInit( void ) {
*/ */
xglEndList(); 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. return 1; // OK, we got here because initialization worked.
@ -283,10 +288,15 @@ void fgStarsRender( void ) {
/* $Log$ /* $Log$
/* Revision 1.9 1998/08/06 12:45:20 curt /* Revision 1.10 1998/08/10 20:33:09 curt
/* Modified to bring in stars in 8 increments based on magnitude, not number /* Rewrote star loading and rendering to:
/* of stars. /* 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 * Revision 1.8 1998/07/13 21:00:10 curt
* Wrote access functions for current fgOPTIONS. * Wrote access functions for current fgOPTIONS.
* *