// nav.hxx -- vor/dme/ndb class // // Written by Curtis Olson, started April 2000. // // Copyright (C) 2000 Curtis L. Olson - curt@flightgear.org // // 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. // // $Id$ #ifndef _FG_NAV_HXX #define _FG_NAV_HXX #include <stdio.h> #include <simgear/compiler.h> #include <simgear/math/sg_geodesy.hxx> #include <simgear/misc/sgstream.hxx> #include <simgear/magvar/magvar.hxx> #include <simgear/timing/sg_time.hxx> #ifdef SG_HAVE_STD_INCLUDES # include <istream> #elif defined( __BORLANDC__ ) || (__APPLE__) # include <iostream> #else # include <istream.h> #endif SG_USING_STD(istream); class FGNav { char type; double lon, lat; double elev; double x, y, z; int freq; int range; bool has_dme; string ident; // to avoid a core dump with corrupt data double magvar; // magvar from true north (negative = W) // for failure modeling string trans_ident; // transmitted ident bool nav_failed; // nav failed? bool dme_failed; // dme failed? public: inline FGNav(void); inline ~FGNav(void) {} inline char get_type() const { return type; } inline double get_lon() const { return lon; } inline double get_lat() const { return lat; } inline double get_elev() const { return elev; } inline double get_x() const { return x; } inline double get_y() const { return y; } inline double get_z() const { return z; } inline int get_freq() const { return freq; } inline int get_range() const { return range; } inline bool get_has_dme() const { return has_dme; } inline const char *get_ident() { return ident.c_str(); } inline string get_trans_ident() { return trans_ident; } inline double get_magvar () const { return magvar; } friend istream& operator>> ( istream&, FGNav& ); }; inline FGNav::FGNav(void) : type(0), lon(0.0), lat(0.0), elev(0.0), x(0.0), y(0.0), z(0.0), freq(0), range(0), has_dme(false), ident(""), magvar(0.0), trans_ident(""), nav_failed(false), dme_failed(false) { } inline istream& operator >> ( istream& in, FGNav& n ) { double f; char c /* , magvar_dir */ ; string magvar_s; static bool first_time = true; static double julian_date = 0; static const double MJD0 = 2415020.0; if ( first_time ) { julian_date = sgTimeCurrentMJD(0,0) + MJD0; first_time = false; } in >> n.type; if ( n.type == '[' ) return in >> skipeol; in >> n.lat >> n.lon >> n.elev >> f >> n.range >> c >> n.ident >> magvar_s; n.freq = (int)(f*100.0 + 0.5); if ( c == 'Y' ) { n.has_dme = true; } else { n.has_dme = false; } // Calculate the magvar from true north. // cout << "Calculating magvar for navaid " << n.ident << endl; if (magvar_s == "XXX") { // default to mag var as of 1990-01-01 (Julian 2447892.5) // cout << "lat = " << n.lat << " lon = " << n.lon << " elev = " // << n.elev << " JD = " // << julian_date << endl; n.magvar = sgGetMagVar( n.lon * SGD_DEGREES_TO_RADIANS, n.lat * SGD_DEGREES_TO_RADIANS, n.elev * SG_FEET_TO_METER, julian_date ) * SGD_RADIANS_TO_DEGREES; // cout << "Default variation at " << n.lon << ',' << n.lat // << " is " << var << endl; #if 0 // I don't know what this is for - CLO 1 Feb 2001 if (var - int(var) >= 0.5) n.magvar = int(var) + 1; else if (var - int(var) <= -0.5) n.magvar = int(var) - 1; else n.magvar = int(var); #endif // cout << "Defaulted to magvar of " << n.magvar << endl; } else { char direction; int var; sscanf(magvar_s.c_str(), "%d%c", &var, &direction); n.magvar = var; if (direction == 'W') n.magvar = -n.magvar; // cout << "Explicit magvar of " << n.magvar << endl; } // cout << n.ident << " " << n.magvar << endl; // generate cartesian coordinates Point3D geod( n.lon * SGD_DEGREES_TO_RADIANS, n.lat * SGD_DEGREES_TO_RADIANS, n.elev ); Point3D cart = sgGeodToCart( geod ); n.x = cart.x(); n.y = cart.y(); n.z = cart.z(); n.trans_ident = n.ident; n.nav_failed = n.dme_failed = false; return in >> skipeol; } #endif // _FG_NAV_HXX