1 // magvar.cxx -- magnetic variation wrapper class
3 // Written by Curtis Olson, started July 2000.
5 // Copyright (C) 2000 Curtis L. Olson - curt@flightgear.org
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
30 #include <simgear/magvar/magvar.hxx>
32 #include "coremag.hxx"
36 SGMagVar::SGMagVar() {
39 SGMagVar::~SGMagVar() {
43 void SGMagVar::update( double lon, double lat, double alt_m, double jd ) {
44 // Calculate local magnetic variation
46 // cout << "alt_m = " << alt_m << endl;
47 magvar = calc_magvar( lat, lon, alt_m / 1000.0, (long)jd, field );
48 magdip = atan(field[5]/sqrt(field[3]*field[3]+field[4]*field[4]));
52 double sgGetMagVar( double lon, double lat, double alt_m, double jd ) {
53 // cout << "lat = " << lat << " lon = " << lon << " elev = " << alt_m
54 // << " JD = " << jd << endl;
57 return calc_magvar( lat, lon, alt_m / 1000.0, (long)jd, field );