174 lines
5.3 KiB
C

/*
* This file is part of the StelD project.
* Copyright 2020 Edward V. Emelianov <edward.emelianoff@gmail.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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include <time.h>
#include "libsofa.h"
#include "usefull_macros.h"
#ifdef EBUG
void reprd(char* s, double ra, double dc){
char pm;
int i[4];
printf ( "%s:", s );
iauA2tf ( 7, ra, &pm, i );
printf ( " %2.2d %2.2d %2.2d.%7.7d", i[0],i[1],i[2],i[3] );
iauA2af ( 6, dc, &pm, i );
printf ( " %c%2.2d %2.2d %2.2d.%6.6d\n", pm, i[0],i[1],i[2],i[3] );
}
void radtodeg(double r){
int i[4]; char pm;
int rem = (int)(r / D2PI);
if(rem) r -= D2PI * rem;
if(r > DPI) r -= D2PI;
else if(r < -DPI) r += D2PI;
iauA2af (2, r, &pm, i);
printf("%c%02d %02d %02d.%2.d", pm, i[0],i[1],i[2],i[3]);
}
#define REP(a,b,c) reprd(a,b,c)
#else
#define REP(a,b,c)
#endif
// temporal stubs for weather/place data; return 0 if all OK
int getPlace(placeData *p){
if(!p) return 0;
/* Site longitude, latitude (radians) and height above the geoid (m). */
p->slong = 0.7232763200;
p->slat = 0.7618977414;
/*
iauAf2a('+', 41, 26, 26.45, &p->slong); // longitude
iauAf2a('+', 43, 39, 12.69, &p->slat); // latitude
*/
p->salt = 2070.0; // altitude
//DBG("long: %.10f, lat: %.10f", p->slong, p->slat);
return 0;
}
int getWeath(placeWeather *w){
if(!w) return 0;
w->relhum = 0.7;
w->tc = 0.;
w->php = 780.;
return 0;
}
int getDUT(almDut *a){
if(!a) return 0;
a->px = a->py = a->DUT1 = 0.;
return 0;
}
/**
* @brief get_MJDt - calculate MJD of date from argument
* @param tval (i) - given date (or NULL for current)
* @param MJD (o) - time
* @return 0 if all OK
*/
int get_MJDt(struct timeval *tval, sMJD *MJD){
struct tm tms;
double tSeconds;
if(!tval){
//DBG("MJD for current time");
struct timeval currentTime;
gettimeofday(&currentTime, NULL);
gmtime_r(&currentTime.tv_sec, &tms);
tSeconds = tms.tm_sec + ((double)currentTime.tv_usec)/1e6;
}else{
gmtime_r(&tval->tv_sec, &tms);
tSeconds = tms.tm_sec + ((double)tval->tv_usec)/1e6;
}
int y, m, d;
y = 1900 + tms.tm_year;
m = tms.tm_mon + 1;
d = tms.tm_mday;
double utc1, utc2;
/* UTC date. */
if(iauDtf2d("UTC", y, m, d, tms.tm_hour, tms.tm_min, tSeconds, &utc1, &utc2) < 0) return -1;
if(!MJD) return 0;
MJD->MJD = utc1 - 2400000.5 + utc2;
MJD->utc1 = utc1;
MJD->utc2 = utc2;
//DBG("UTC(m): %g, %.8f\n", utc1 - 2400000.5, utc2);
if(iauUtctai(utc1, utc2, &MJD->tai1, &MJD->tai2)) return -1;
//DBG("TAI");
if(iauTaitt(MJD->tai1, MJD->tai2, &MJD->tt1, &MJD->tt2)) return -1;
//DBG("TT");
return 0;
}
/**
* @brief get_ObsPlace - calculate observed place (without PM etc) for given date @550nm
* @param tval (i) - time
* @param p2000 (i) - polar coordinates for J2000 (only ra/dec used)
* @param pnow (o) - polar coordinates for given epoch (or NULL)
* @param hnow (o) - horizontal coordinates for given epoch (or NULL)
* @return 0 if all OK
*/
int get_ObsPlace(struct timeval *tval, polarCrds *p2000, polarCrds *pnow, horizCrds *hnow){
double pr = 0.0; // RA proper motion (radians/year; Note 2)
double pd = 0.0; // Dec proper motion (radians/year)
double px = 0.0; // parallax (arcsec)
double rv = 0.0; // radial velocity (km/s, positive if receding)
sMJD MJD;
if(get_MJDt(tval, &MJD)) return -1;
if(!p2000) return -1;
placeData p;
placeWeather w;
almDut d;
if(getPlace(&p)) return -1;
if(getWeath(&w)) return -1;
if(getDUT(&d)) return -1;
/* Effective wavelength (microns) */
double wl = 0.55;
/* ICRS to observed. */
double aob, zob, hob, dob, rob, eo;
/*
DBG("iauAtco13(%g, %g, %g, %g, %g, %g, %g, %g, %g, %g, %g, %g, %g, %g, %g, %g, %g, %g)",
p2000->ra, p2000->dec, pr, pd, px, rv, MJD.utc1, MJD.utc2, d.DUT1, p.slong, p.slat, p.salt,
d.px, d.py, w.php, w.tc, w.relhum, wl);
*/
if(iauAtco13(p2000->ra, p2000->dec,
pr, pd, px, rv,
MJD.utc1, MJD.utc2,
d.DUT1,
p.slong, p.slat, p.salt,
d.px, d.py,
w.php, w.tc, w.relhum,
wl,
&aob, &zob,
&hob, &dob, &rob, &eo)) return -1;
REP("ICRS->observed", rob, dob);
if(pnow){
pnow->eo = eo;
pnow->ha = hob;
pnow->ra = rob;
pnow->dec = dob;
}
if(hnow){
hnow->az = aob;
hnow->zd = zob;
}
#ifdef EBUG
printf("A(bta)/Z: ");
radtodeg(aob);
printf("("); radtodeg(DPI-aob);
printf(")/"); radtodeg(zob);
printf("\n");
#endif
return 0;
}