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satorbit.c
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satorbit.c
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#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>
#include <getopt.h>
#include "cpgplot.h"
#include "sgdp4h.h"
#define LIM 128
#define NMAX 1024
#define MMAX 28368
#define D2R M_PI/180.0
#define R2D 180.0/M_PI
#define XKMPER 6378.135 // Earth radius in km
#define FLAT (1.0/298.257)
#define XKMPAU 149597879.691 // AU in km
long Isat=0;
long Isatsel=0;
extern double SGDP4_jd0;
struct coeff_lr {
int nd,nm,nm1,nf;
double sa,ca;
} clr[60];
struct coeff_b {
int nd,nm,nm1,nf;
double sa;
} cb[60];
struct map {
long satno;
double l0,b0,h0;
double lat,lng;
double mjd;
float alt,timezone;
int length;
char orientation[LIM];
char nfd[LIM],tlefile[LIM],observer[32];
char datadir[LIM],tledir[LIM],notamfile[LIM],xyzfile[LIM];
int site_id,notamflag,xyzflag,moonflag,launchsitesflag;
int plotfootprint;
float w;
} m;
struct globe {
int n;
float l[MMAX],b[MMAX],x[MMAX],y[MMAX],z[MMAX];
} glb;
struct sat {
long Isat;
double jd;
double dx,dy,dz;
double x,y,z,vx,vy,vz;
double rsun,rearth;
double psun,pearth,p;
double r,ra,de;
double azi,alt;
double rx,ry;
double lng,lat;
};
void read_globe(void);
void plot_globe(void);
double nfd2mjd(char *date);
double date2mjd(int year,int month,double day);
void mjd2date(double mjd,char *date,int length);
void usage();
void nfd_now(char *s);
void rotate(int axis,float angle,float *x,float *y,float *z);
void sunpos_xyz(double mjd,xyz_t *pos,double *ra,double *de);
void lunpos_xyz(double mjd,xyz_t *pos,double *ra,double *de);
double gmst(double);
double dgmst(double);
double modulo(double,double);
void get_site(int site_id);
void ecliptical2equatorial(double l,double b,double *ra,double *de);
void plot_launch_sites(void);
// Initialize setup
void initialize_setup(void)
{
int i;
FILE *file;
char *env,filename[128];
// Default parameters
m.satno=0;
m.timezone=0.0;
m.length=60;
strcpy(m.orientation,"terrestial");
nfd_now(m.nfd);
m.mjd=nfd2mjd(m.nfd);
m.w=1.2;
m.h0=gmst(m.mjd);
m.notamflag=0;
m.xyzflag=0;
m.moonflag=0;
m.launchsitesflag=0;
m.plotfootprint=1;
// Default settings
strcpy(m.observer,"Unknown");
m.site_id=0;
// Get environment variables
env=getenv("ST_DATADIR");
if (env!=NULL) {
strcpy(m.datadir,env);
} else {
printf("ST_DATADIR environment variable not found.\n");
}
env=getenv("ST_COSPAR");
if (env!=NULL) {
get_site(atoi(env));
} else {
printf("ST_COSPAR environment variable not found.\n");
}
env=getenv("ST_TLEDIR");
if (env!=NULL) {
strcpy(m.tledir,env);
} else {
printf("ST_TLEDIR environment variable not found.\n");
}
// sprintf(m.tlefile,"%s/classfd.tle",m.tledir);
strcpy(m.tlefile,"");
// Read LR coefficients
sprintf(filename,"%s/data/moonLR.dat",m.datadir);
file=fopen(filename,"r");
for (i=0;i<60;i++)
fscanf(file,"%d %d %d %d %lf %lf",&clr[i].nd,&clr[i].nm,&clr[i].nm1,&clr[i].nf,&clr[i].sa,&clr[i].ca);
fclose(file);
// Read B coefficients
sprintf(filename,"%s/data/moonB.dat",m.datadir);
file=fopen(filename,"r");
for (i=0;i<60;i++)
fscanf(file,"%d %d %d %d %lf",&cb[i].nd,&cb[i].nm,&cb[i].nm1,&cb[i].nf,&cb[i].sa);
fclose(file);
return;
}
// Convert ecliptical into equatorial coordinates
void ecliptical2equatorial(double l,double b,double *ra,double *de)
{
double eps=23.4392911;
*ra=modulo(atan2(sin(l*D2R)*cos(eps*D2R)-tan(b*D2R)*sin(eps*D2R),cos(l*D2R))*R2D,360.0);
*de=asin(sin(b*D2R)*cos(eps*D2R)+cos(b*D2R)*sin(eps*D2R)*sin(l*D2R))*R2D;
return;
}
void plot_footprint(struct sat s)
{
int i,j,flag;
float range,alpha,dist,zz,theta,rr;
float x,y,z,x0,y0,z0,r0,r;
// Foot print size
range=sqrt(s.x*s.x+s.y*s.y+s.z*s.z);
dist=sqrt(range*range-XKMPER*XKMPER);
alpha=acos(XKMPER/range);
zz=range-dist*sin(alpha);
rr=sqrt(XKMPER*XKMPER-zz*zz);
// Sub satellite point
z=cos(s.lng*D2R)*cos(s.lat*D2R)*XKMPER;
x=sin(s.lng*D2R)*cos(s.lat*D2R)*XKMPER;
y=sin(s.lat*D2R)*XKMPER;
rotate(1,m.l0,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
r=sqrt(x*x+y*y);
z0=cos(s.lng*D2R)*cos(s.lat*D2R)*range;
x0=sin(s.lng*D2R)*cos(s.lat*D2R)*range;
y0=sin(s.lat*D2R)*range;
rotate(1,m.l0,&x0,&y0,&z0);
rotate(0,m.b0,&x0,&y0,&z0);
r0=sqrt(x0*x0+y0*y0);
if (r<XKMPER && z<0.0) {
x*=XKMPER/r;
y*=XKMPER/r;
}
if (r0>XKMPER || (r0<XKMPER && z0>0.0)) {
cpgmove(x0,y0);
cpgdraw(x,y);
}
if (z>0.0)
cpgpt1(x,y,4);
for (i=0,j=0,flag=0;i<NMAX;i++,j++) {
theta=2.0*M_PI*(float) i/(float) (NMAX-1);
x=rr*sin(theta);
y=rr*cos(theta);
z=zz;
rotate(0,-s.lat,&x,&y,&z);
rotate(1,-s.lng,&x,&y,&z);
rotate(1,m.l0,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
if (flag==0)
cpgmove(x,y);
else
cpgdraw(x,y);
if (z>0.0)
flag=1;
else
flag=0;
}
return;
}
// Computes apparent position
struct sat apparent_position(double mjd)
{
struct sat s;
double jd,rsun,rearth;
double dx,dy,dz;
xyz_t satpos,obspos,satvel,sunpos;
double sra,sde;
// Sat ID
s.Isat=Isat;
// Get Julian Date
jd=mjd+2400000.5;
// Get positions
satpos_xyz(jd,&satpos,&satvel);
sunpos_xyz(mjd,&sunpos,&sra,&sde);
// Sat positions
s.x=satpos.x;
s.y=satpos.y;
s.z=satpos.z;
s.vx=satvel.x;
s.vy=satvel.y;
s.vz=satvel.y;
// Sun position from satellite
dx=-satpos.x+sunpos.x;
dy=-satpos.y+sunpos.y;
dz=-satpos.z+sunpos.z;
// Distances
rsun=sqrt(dx*dx+dy*dy+dz*dz);
rearth=sqrt(satpos.x*satpos.x+satpos.y*satpos.y+satpos.z*satpos.z);
// Angles
s.psun=asin(696.0e3/rsun)*R2D;
s.pearth=asin(6378.135/rearth)*R2D;
s.p=acos((-dx*satpos.x-dy*satpos.y-dz*satpos.z)/(rsun*rearth))*R2D;
// s.p=acos(((sunpos.x+satpos.x)*satpos.x+(sunpos.y+satpos.y)*satpos.y+(sunpos.z+satpos.z)*satpos.z)/(rsun*rearth))*R2D;
s.p-=s.pearth;
// Celestial position
s.r=sqrt(satpos.x*satpos.x+satpos.y*satpos.y+satpos.z*satpos.z);
s.ra=atan2(satpos.y,satpos.x)*R2D;
s.de=asin(satpos.z/s.r)*R2D;
// Latitude and longitude
s.lng=s.ra-gmst(m.mjd);;
s.lat=s.de;
return s;
}
// plot satellite track
void plot_track(void)
{
int i=0,nstep=500;
orbit_t orb;
xyz_t pos,vel;
double jd,dt,h,mjd;
FILE *fp=NULL;
float x,y,z,r,v;
long imode;
int isci;
float isch;
char norad[7];
struct sat s;
float rmin,rmax;
float xmin,ymin,zmin,xmax,ymax,zmax;
if (strcmp(m.tlefile,"")==0)
return;
cpgqci(&isci);
cpgqch(&isch);
cpgsci(7);
fp=fopen(m.tlefile,"rb");
if (fp==NULL) {
fatal_error("File open failed for reading \"%s\"",m.tlefile);
}
while (read_twoline(fp,m.satno,&orb) == 0) {
// print_orb(&orb);
Isat=orb.satno;
imode=init_sgdp4(&orb);
if(imode == SGDP4_ERROR) continue;
jd=m.mjd+2400000.5;
h=gmst(m.mjd);
for (i=0,dt=0.0;;i++) {
//if(satpos_xyz(jd, &pos, &vel) == SGDP4_ERROR) break;
mjd=jd-2400000.5;
s=apparent_position(mjd);
x=s.x;
y=s.y;
z=s.z;
rotate(0,-90.0,&x,&y,&z);
rotate(1,90.0,&x,&y,&z);
rotate(1,m.l0+h,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
// Visibility
if (s.p<-s.psun)
cpgsci(14);
else if (s.p>-s.psun && s.p<s.psun)
cpgsci(15);
else if (s.p>s.psun)
cpgsci(7);
// Find perigee and apogee
if (i==0) {
rmin=s.r;
rmax=s.r;
} else {
if (s.r<rmin) {
rmin=s.r;
xmin=x;
ymin=y;
zmin=z;
}
if (s.r>rmax) {
rmax=s.r;
xmax=x;
ymax=y;
zmax=z;
}
}
// Plot
if (i==0) {
if (m.plotfootprint==1)
plot_footprint(s);
if (!(sqrt(x*x+y*y)<XKMPER && z<0.0)) {
sprintf(norad," %ld",Isat);
cpgsch(0.6);
cpgtext(x,y,norad);
cpgsch(isch);
cpgpt1(x,y,17);
}
cpgmove(x,y);
} else if (s.r>XKMPER) {
if (sqrt(x*x+y*y)<XKMPER && z<0.0)
cpgmove(x,y);
else
cpgdraw(x,y);
}
// Do timestep
r=sqrt(s.x*s.x+s.y*s.y+s.z*s.z);
v=sqrt(s.vx*s.vx+s.vy*s.vy+s.vz*s.vz);
dt=2.0*M_PI*r/(0.75*v*nstep);
jd+=dt/86400.0;
if (i==nstep)
break;
}
if (!(sqrt(xmin*xmin+ymin*ymin)<XKMPER && zmin<0.0))
cpgpt1(xmin,ymin,4);
if (!(sqrt(xmax*xmax+ymax*ymax)<XKMPER && zmax<0.0))
cpgpt1(xmax,ymax,6);
}
cpgsls(1);
cpgsci(isci);
cpgsch(isch);
return;
}
// plot satellite track
void plot_xyz(void)
{
int i=0,nstep=500,flag=0;
orbit_t orb;
xyz_t pos,vel;
double jd,dt,h,mjd,mjd0;
FILE *fp=NULL;
float x,y,z,r,v;
long imode;
int isci;
float isch;
char norad[7],line[LIM],nfd[32];
struct sat s;
double rsun,rearth;
double dx,dy,dz,sra,sde;
xyz_t sunpos,satpos;
cpgqci(&isci);
cpgqch(&isch);
cpgsci(8);
fp=fopen(m.xyzfile,"rb");
if (fp==NULL) {
fatal_error("File open failed for reading \"%s\"",m.xyzfile);
}
h=gmst(m.mjd);
while (fgetline(fp,line,LIM)>0) {
// Get satellite position
if (line[10]=='T') {
sscanf(line,"%s %lf %lf %lf",nfd,&satpos.x,&satpos.y,&satpos.z);
mjd=nfd2mjd(nfd);
} else {
sscanf(line,"%lf %lf %lf %lf",&mjd,&satpos.x,&satpos.y,&satpos.z);
}
// Mark point to plot
if (mjd>m.mjd && mjd0<=m.mjd && flag==0 && i>0)
flag=1;
// Get positions
sunpos_xyz(m.mjd,&sunpos,&sra,&sde);
// Sun position from satellite
dx=-satpos.x+sunpos.x;
dy=-satpos.y+sunpos.y;
dz=-satpos.z+sunpos.z;
// Distances
rsun=sqrt(dx*dx+dy*dy+dz*dz);
rearth=sqrt(satpos.x*satpos.x+satpos.y*satpos.y+satpos.z*satpos.z);
// Angles
s.psun=asin(696.0e3/rsun)*R2D;
s.pearth=asin(6378.135/rearth)*R2D;
s.p=acos((-dx*satpos.x-dy*satpos.y-dz*satpos.z)/(rsun*rearth))*R2D;
// s.p=acos(((sunpos.x+satpos.x)*satpos.x+(sunpos.y+satpos.y)*satpos.y+(sunpos.z+satpos.z)*satpos.z)/(rsun*rearth))*R2D;
s.p-=s.pearth;
// Celestial position
s.r=sqrt(satpos.x*satpos.x+satpos.y*satpos.y+satpos.z*satpos.z);
s.ra=atan2(satpos.y,satpos.x)*R2D;
s.de=asin(satpos.z/s.r)*R2D;
// Latitude and longitude
s.lng=s.ra-gmst(m.mjd);;
s.lat=s.de;
s.x=satpos.x;
s.y=satpos.y;
s.z=satpos.z;
x=satpos.x;
y=satpos.y;
z=satpos.z;
rotate(0,-90.0,&x,&y,&z);
rotate(1,90.0,&x,&y,&z);
rotate(1,m.l0+h,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
// Visibility
if (s.p<-s.psun)
cpgsci(14);
else if (s.p>-s.psun && s.p<s.psun)
cpgsci(15);
else if (s.p>s.psun)
cpgsci(7);
// Plot
if (flag==1) {
flag=2;
if (m.plotfootprint==1)
plot_footprint(s);
if (!(sqrt(x*x+y*y)<XKMPER && z<0.0)) {
sprintf(norad," xyz");
cpgsch(0.6);
cpgtext(x,y,norad);
cpgsch(isch);
cpgpt1(x,y,17);
}
}
if (i==0) {
cpgmove(x,y);
i++;
} else if (s.r>XKMPER) {
if (sqrt(x*x+y*y)<XKMPER && z<0.0)
cpgmove(x,y);
else
cpgdraw(x,y);
}
mjd0=mjd;
}
cpgsls(1);
cpgsci(isci);
cpgsch(isch);
return;
}
void read_globe(void)
{
int i,status;
FILE *file;
float l,b;
char filename[LIM];
sprintf(filename,"%s/data/globe.dat",m.datadir);
file=fopen(filename,"r");
for (i=0;i<MMAX;i++) {
status=fscanf(file,"%f %f",&glb.b[i],&glb.l[i]);
l=glb.l[i]*D2R;
b=glb.b[i]*D2R;
glb.z[i]=XKMPER*cos(l)*cos(b);
glb.x[i]=XKMPER*sin(l)*cos(b);
glb.y[i]=XKMPER*sin(b);
}
fclose(file);
glb.n=MMAX;
return;
}
void plot_globe(void)
{
int i,flag;
float x,y,z;
for (i=0,flag=0;i<glb.n;i++) {
if (glb.b[i]==9999.0) {
flag=0;
continue;
}
x=glb.x[i];
y=glb.y[i];
z=glb.z[i];
rotate(1,m.l0,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
if (z>0.0) {
if (flag==0) {
cpgmove(x,y);
flag=1;
} else {
cpgdraw(x,y);
}
} else {
flag=0;
}
}
return;
}
// plot grid
void plot_grid(void)
{
int i,j,flag;
float l,b;
float x,y,z;
for (l=0.0;l<=360.0;l+=30.0) {
for (b=-90.0,flag=0;b<=90.0;b+=1.0) {
z=cos(l*D2R)*cos(b*D2R)*XKMPER;
x=sin(l*D2R)*cos(b*D2R)*XKMPER;
y=sin(b*D2R)*XKMPER;
rotate(1,m.l0,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
if (flag==0)
cpgmove(x,y);
else
cpgdraw(x,y);
if (z>0.0)
flag=1;
else
flag=0;
}
}
for (b=-90.0;b<=90.0;b+=30.0) {
for (l=0.0,flag=0;l<=360.0;l+=1.0) {
z=cos(l*D2R)*cos(b*D2R)*XKMPER;
x=sin(l*D2R)*cos(b*D2R)*XKMPER;
y=sin(b*D2R)*XKMPER;
rotate(1,m.l0,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
if (flag==0)
cpgmove(x,y);
else
cpgdraw(x,y);
if (z>0.0)
flag=1;
else
flag=0;
}
}
return;
}
// Plot terminator
void plot_moon(void)
{
xyz_t s;
float r,h;
float l,b,l0,b0;
float x0,y0,z0,x,y,z;
double lra,lde,dmjd;
int isci;
char text[8];
cpgqci(&isci);
cpgsci(3);
// Get positions
lunpos_xyz(m.mjd,&s,&lra,&lde);
// GMST
h=gmst(m.mjd);
// Lunar subpoint
l0=modulo(lra-h,360.0);
b0=lde;
if (l0>180.0)
l0-=360.0;
// Convert
z0=cos(l0*D2R)*cos(b0*D2R)*XKMPER;
x0=sin(l0*D2R)*cos(b0*D2R)*XKMPER;
y0=sin(b0*D2R)*XKMPER;
rotate(1,m.l0,&x0,&y0,&z0);
rotate(0,m.b0,&x0,&y0,&z0);
// Plot sub lunar point
if (z0>0.0)
cpgpt1(x0,y0,17);
// Lunar antipode
l0=modulo(lra-h-180,360.0);
b0=-lde;
if (l0>180.0)
l0-=360.0;
// Convert
z0=cos(l0*D2R)*cos(b0*D2R)*XKMPER;
x0=sin(l0*D2R)*cos(b0*D2R)*XKMPER;
y0=sin(b0*D2R)*XKMPER;
rotate(1,m.l0,&x0,&y0,&z0);
rotate(0,m.b0,&x0,&y0,&z0);
// Plot antipode
if (z0>0.0)
cpgpt1(x0,y0,6);
// Plot moon
z=s.z;
x=s.x;
y=s.y;
rotate(0,-90.0,&x,&y,&z);
rotate(1,90.0,&x,&y,&z);
rotate(1,m.l0+h,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
cpgcirc(x,y,1737.5);
// Plot antipode travel
for (dmjd=1.0;dmjd<7.0;dmjd+=1.0) {
// Get positions
lunpos_xyz(m.mjd+dmjd,&s,&lra,&lde);
// GMST
h=gmst(m.mjd);
// Lunar antipode
l0=modulo(lra-h-180,360.0);
b0=-lde;
if (l0>180.0)
l0-=360.0;
// Convert
z0=cos(l0*D2R)*cos(b0*D2R)*XKMPER;
x0=sin(l0*D2R)*cos(b0*D2R)*XKMPER;
y0=sin(b0*D2R)*XKMPER;
rotate(1,m.l0,&x0,&y0,&z0);
rotate(0,m.b0,&x0,&y0,&z0);
// Plot antipode
if (z0>0.0) {
sprintf(text," %.0f",dmjd);
cpgpt1(x0,y0,2);
cpgtext(x0,y0,text);
}
}
for (dmjd=-6.0;dmjd<0.0;dmjd+=1.0) {
// Get positions
lunpos_xyz(m.mjd+dmjd,&s,&lra,&lde);
// GMST
h=gmst(m.mjd);
// Lunar antipode
l0=modulo(lra-h-180,360.0);
b0=-lde;
if (l0>180.0)
l0-=360.0;
// Convert
z0=cos(l0*D2R)*cos(b0*D2R)*XKMPER;
x0=sin(l0*D2R)*cos(b0*D2R)*XKMPER;
y0=sin(b0*D2R)*XKMPER;
rotate(1,m.l0,&x0,&y0,&z0);
rotate(0,m.b0,&x0,&y0,&z0);
// Plot antipode
if (z0>0.0) {
sprintf(text," %.0f",dmjd);
cpgpt1(x0,y0,2);
cpgtext(x0,y0,text);
}
}
cpgsci(isci);
return;
}
// Plot terminator
void plot_terminator(void)
{
int i,j,k,flag,j1,j2;
double jd;
xyz_t s;
float r,h;
float l,b,l0,b0;
float x0,y0,z0;
float x,y,z,t0,t1,t2,t;
float xx[NMAX],yy[NMAX],zz[NMAX];
float xt[NMAX],yt[NMAX],zt[NMAX];
int isci;
double sra,sde;
float theta;
float ang[]={0.0,-6.0,-12.0,-18.0};
cpgqci(&isci);
// Get positions
sunpos_xyz(m.mjd,&s,&sra,&sde);
// GMST
h=gmst(m.mjd);
// Solar subpoint
l0=modulo(sra-h,360.0);
b0=sde;
if (l0>180.0)
l0-=360.0;
// Convert
z0=cos(l0*D2R)*cos(b0*D2R)*XKMPER;
x0=sin(l0*D2R)*cos(b0*D2R)*XKMPER;
y0=sin(b0*D2R)*XKMPER;
rotate(1,m.l0,&x0,&y0,&z0);
rotate(0,m.b0,&x0,&y0,&z0);
t0=atan2(y0,x0)*R2D;
// Loop over terminator boundaries
for (i=0,j=0,flag=0;i<NMAX;i++,j++) {
theta=2.0*M_PI*(float) i/(float) (NMAX-1);
x=XKMPER*sin(theta);
y=XKMPER*cos(theta);
z=0.0;
rotate(0,-b0,&x,&y,&z);
rotate(1,-l0,&x,&y,&z);
rotate(1,m.l0,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
xx[i]=x;
yy[i]=y;
zz[i]=z;
}
for (i=0,j=0;i<NMAX;i++) {
if (i>0 && zz[i]*zz[i-1]<0.0) {
if (zz[i]>0.0 && zz[i-1]<0.0) {
t1=atan2(yy[i],xx[i])*R2D;
j1=i;
} else {
t2=atan2(yy[i],xx[i])*R2D;
j2=i;
}
}
}
// angles
t0=modulo(t0,360);
t1=modulo(t1,360);
t2=modulo(t2,360);
if (t1<t2)
t1+=360.0;
if (abs(j2-j1)>512)
j2++;
if (abs(j2-j1)<512)
j2--;
if (j1>j2) {
for (i=0,j=0;i<j2;i++,j++) {
xt[j]=xx[i];
yt[j]=yy[i];
}
for (i=0;i<NMAX-abs(j2-j1);i++,j++) {
t=t2-(t2-t1)*(float) i/(float) (NMAX-abs(j2-j1));
xt[j]=XKMPER*cos(t*D2R);
yt[j]=XKMPER*sin(t*D2R);
}
for (i=j1;i<NMAX;i++,j++) {
xt[j]=xx[i];
yt[j]=yy[i];
}
} else {
for (i=j1,j=0;i<j2;i++,j++) {
xt[j]=xx[i];
yt[j]=yy[i];
}
for (i=0;i<NMAX-abs(j2-j1);i++,j++) {
t=t2-(t2-t1)*(float) i/(float) (NMAX-abs(j2-j1));
xt[j]=XKMPER*cos(t*D2R);
yt[j]=XKMPER*sin(t*D2R);
}
}
// Plot day side
cpgscr(17,0.0,0.0,0.7);
cpgsci(17);
cpgsfs(1);
cpgcirc(0.0,0.0,XKMPER);
// Plot night side
cpgscr(16,0.0,0.0,0.2);
cpgsci(16);
cpgpoly(NMAX,xt,yt);
// Plot
if (z0>0.0) {
cpgsci(7);
cpgpt1(x0,y0,17);
}
// Loop over terminator boundaries
for (k=0;k<4;k++) {
if (k==0)
cpgsci(2);
else
cpgsci(4);
for (i=0,j=0,flag=0;i<NMAX;i++,j++) {
theta=2.0*M_PI*(float) i/(float) (NMAX-1);
x=XKMPER*sin(theta)*cos(ang[k]*D2R);
y=XKMPER*cos(theta)*cos(ang[k]*D2R);
z=XKMPER*sin(ang[k]*D2R);
rotate(0,-b0,&x,&y,&z);
rotate(1,-l0,&x,&y,&z);
rotate(1,m.l0,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
if (flag==0)
cpgmove(x,y);
else
cpgdraw(x,y);
if (z>0.0)
flag=1;
else
flag=0;
}
}
cpgsci(isci);
return;
}
// Read a line of maximum length int lim from file FILE into string s
int fgetline(FILE *file,char *s,int lim)
{
int c,i=0;
while (--lim > 0 && (c=fgetc(file)) != EOF && c != '\n')
s[i++] = c;
if (c == '\t')
c=' ';
if (c == '\n')
s[i++] = c;
s[i] = '\0';
return i;
}
void plot_notam(char *filename)
{
int i,flag=0;
float x,y,z;
float l,b,r;
char line[LIM];
FILE *file;
file=fopen(filename,"r");
while (fgetline(file,line,LIM)>0) {
r=0.0;
sscanf(line,"%f %f %f",&b,&l,&r);
if (strlen(line)<2) {
flag=0;
continue;
}
z=cos(l*D2R)*cos(b*D2R)*XKMPER;
x=sin(l*D2R)*cos(b*D2R)*XKMPER;
y=sin(b*D2R)*XKMPER;
rotate(1,m.l0,&x,&y,&z);
rotate(0,m.b0,&x,&y,&z);
if (z>0.0) {
if (flag==0) {
cpgmove(x,y);
flag=1;
} else {
cpgdraw(x,y);
}
} else {
flag=0;
}
}
return;
}
void plot_map(int plotflag)
{
int redraw=1,status;
char text[256];
float x,y,z;
char c;
for (;;) {
if (redraw>0) {
// Get present mjd
if (m.mjd<0.0) {
nfd_now(m.nfd);
m.mjd=nfd2mjd(m.nfd);
m.h0=gmst(m.mjd);
}
// Update position
if (strcmp(m.orientation,"terrestial")==0) {
m.l0=m.lng;
m.b0=m.lat;
} else if (strcmp(m.orientation,"sidereal")==0) {
m.l0=m.lng-gmst(m.mjd)+m.h0;
m.b0=m.lat;
}
cpgscr(0,0.0,0.0,0.0);
cpgeras();
// Create window
cpgsvp(0.05,0.95,0.05,0.95);
cpgwnad(-m.w*XKMPER,m.w*XKMPER,-m.w*XKMPER,m.w*XKMPER);