--- /dev/null
+// mkrbeacons.cxx -- marker beacon management class
+//
+// Written by Curtis Olson, started March 2001.
+//
+// Copyright (C) 2001 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.
+//
+// $Id$
+
+
+#include "mkrbeacons.hxx"
+
+
+// constructor
+FGBeacon::FGBeacon() {
+ FGBeacon( 0, 0, 0, NOBEACON );
+}
+
+FGBeacon::FGBeacon( double _lon, double _lat, double _elev,
+ fgMkrBeacType _type ) {
+ lon = _lon;
+ lat = _lat;
+ elev = _elev;
+ type = _type;
+
+ Point3D pos = sgGeodToCart(Point3D(lon * DEG_TO_RAD, lat * DEG_TO_RAD, 0));
+ // cout << "pos = " << pos << endl;
+ x = pos.x();
+ y = pos.y();
+ z = pos.z();
+}
+
+// destructor
+FGBeacon::~FGBeacon() {
+}
+
+
+// constructor
+FGMarkerBeacons::FGMarkerBeacons() {
+}
+
+// destructor
+FGMarkerBeacons::~FGMarkerBeacons() {
+}
+
+
+// initialize the structures
+bool FGMarkerBeacons::init() {
+ // erase the beacon map
+ beacon_map.clear();
+
+ return true;
+}
+
+
+// real add a marker beacon
+bool FGMarkerBeacons::real_add( const int master_index, const FGBeacon& b ) {
+ // cout << "Master index = " << master_index << endl;
+ beacon_map[master_index].push_back( b );
+
+ return true;
+}
+
+
+// front end for add a marker beacon
+bool FGMarkerBeacons::add( double lon, double lat, double elev,
+ FGBeacon::fgMkrBeacType type ) {
+ double diff;
+
+ int lonidx = (int)lon;
+ diff = lon - (double)lonidx;
+ if ( (lon < 0.0) && (fabs(diff) > FG_EPSILON) ) {
+ lonidx -= 1;
+ }
+ double lonfrac = lon - (double)lonidx;
+ lonidx += 180;
+
+ int latidx = (int)lat;
+ diff = lat - (double)latidx;
+ if ( (lat < 0.0) && (fabs(diff) > FG_EPSILON) ) {
+ latidx -= 1;
+ }
+ double latfrac = lat - (double)latidx;
+ latidx += 90;
+
+ int master_index = lonidx * 1000 + latidx;
+ FGBeacon b( lon, lat, elev, type );
+
+ // add to the actual bucket
+ real_add( master_index, b );
+
+ // if we are close to the edge, add to adjacent buckets so we only
+ // have to search one bucket at run time
+
+ // there are 8 cases since there are 8 adjacent tiles
+
+ if ( lonfrac < 0.2 ) {
+ real_add( master_index - 1000, b );
+ if ( latfrac < 0.2 ) {
+ real_add( master_index - 1000 - 1, b );
+ } else if ( latfrac > 0.8 ) {
+ real_add( master_index - 1000 + 1, b );
+ }
+ } else if ( lonfrac > 0.8 ) {
+ real_add( master_index + 1000, b );
+ if ( latfrac < 0.2 ) {
+ real_add( master_index + 1000 - 1, b );
+ } else if ( latfrac > 0.8 ) {
+ real_add( master_index+- 1000 + 1, b );
+ }
+ } else if ( latfrac < 0.2 ) {
+ real_add( master_index - 1, b );
+ } else if ( latfrac > 0.8 ) {
+ real_add( master_index + 1, b );
+ }
+
+ return true;
+}
+
+
+// returns marker beacon type if we are over a marker beacon, NOBEACON
+// otherwise
+FGBeacon::fgMkrBeacType FGMarkerBeacons::query( double lon, double lat,
+ double elev ) {
+ double diff;
+
+ int lonidx = (int)lon;
+ diff = lon - (double)lonidx;
+ if ( (lon < 0.0) && (fabs(diff) > FG_EPSILON) ) {
+ lonidx -= 1;
+ }
+ lonidx += 180;
+
+ int latidx = (int)lat;
+ diff = lat - (double)latidx;
+ if ( (lat < 0.0) && (fabs(diff) > FG_EPSILON) ) {
+ latidx -= 1;
+ }
+ latidx += 90;
+
+ int master_index = lonidx * 1000 + latidx;
+
+ beacon_list_type beacons = beacon_map[ master_index ];
+ // cout << "Master index = " << master_index << endl;
+ // cout << "beacon search length = " << beacons.size() << endl;
+
+ beacon_list_iterator current = beacons.begin();
+ beacon_list_iterator last = beacons.end();
+
+ Point3D aircraft = sgGeodToCart(Point3D(lon*DEG_TO_RAD, lat*DEG_TO_RAD, 0));
+
+ double min_dist = 999999999.0;
+
+ for ( ; current != last ; ++current ) {
+ // cout << " testing " << current->get_locident() << endl;
+ Point3D station = Point3D( current->get_x(),
+ current->get_y(),
+ current->get_z() );
+ // cout << " aircraft = " << aircraft << " station = " << station
+ // << endl;
+
+ double d = aircraft.distance3Dsquared( station );
+ // cout << " distance = " << d << " ("
+ // << FG_ILS_DEFAULT_RANGE * NM_TO_METER
+ // * FG_ILS_DEFAULT_RANGE * NM_TO_METER
+ // << ")" << endl;
+
+ // cout << " range = " << sqrt(d) << endl;
+
+ if ( d < min_dist ) {
+ min_dist = d;
+ }
+
+ // cout << "elev = " << elev * METER_TO_FEET
+ // << " current->get_elev() = " << current->get_elev() << endl;
+ double delev = elev * METER_TO_FEET - current->get_elev();
+ double maxrange = 4200 * delev / 1000;
+ // cout << "delev = " << delev << " maxrange = " << maxrange << endl;
+
+ // match up to twice the published range so we can model
+ // reduced signal strength
+ if ( d < maxrange * maxrange ) {
+ // cout << "lon = " << lon << " lat = " << lat
+ // << " closest beacon = " << sqrt( min_dist ) << endl;
+ return current->get_type();
+ }
+ }
+
+ // cout << "lon = " << lon << " lat = " << lat
+ << " closest beacon = " << sqrt( min_dist ) << endl;
+
+ return FGBeacon::NOBEACON;
+}
+
+
+FGMarkerBeacons *current_beacons;
--- /dev/null
+// mkrbeacons.hxx -- marker beacon management class
+//
+// Written by Curtis Olson, started March 2001.
+//
+// Copyright (C) 2001 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_MKRBEACON_HXX
+#define _FG_MKRBEACON_HXX
+
+
+#include <simgear/compiler.h>
+#include <simgear/misc/fgpath.hxx>
+
+#include <map>
+#include <vector>
+
+#include "nav.hxx"
+
+FG_USING_STD(map);
+FG_USING_STD(vector);
+
+
+class FGBeacon {
+
+public:
+
+ enum fgMkrBeacType {
+ NOBEACON = 0,
+ INNER,
+ MIDDLE,
+ OUTER
+ };
+
+private:
+
+ double lon;
+ double lat;
+ double elev;
+ fgMkrBeacType type;
+
+ double x, y, z;
+
+public:
+
+ FGBeacon();
+ FGBeacon( double _lon, double _lat, double _elev, fgMkrBeacType _type );
+ ~FGBeacon();
+
+ inline double get_elev() const { return elev; }
+ inline fgMkrBeacType get_type() const { return type; }
+ inline double get_x() const { return x; }
+ inline double get_y() const { return y; }
+ inline double get_z() const { return z; }
+
+};
+
+
+class FGMarkerBeacons {
+
+ // convenience types
+ typedef vector < FGBeacon > beacon_list_type;
+ typedef beacon_list_type::iterator beacon_list_iterator;
+ typedef beacon_list_type::const_iterator beacon_list_const_iterator;
+
+ typedef map < int, beacon_list_type > beacon_map_type;
+ typedef beacon_map_type::iterator beacon_map_iterator;
+ typedef beacon_map_type::const_iterator beacon_map_const_iterator;
+
+ beacon_map_type beacon_map;
+
+ // real add a marker beacon
+ bool FGMarkerBeacons::real_add( const int master_index, const FGBeacon& b );
+
+public:
+
+ FGMarkerBeacons();
+ ~FGMarkerBeacons();
+
+ // initialize the structures
+ bool init();
+
+ // add a marker beacon
+ bool add( double lon, double lat, double elev,
+ FGBeacon::fgMkrBeacType type );
+
+ // returns marker beacon type if we are over a marker beacon, NOBEACON
+ // otherwise
+ FGBeacon::fgMkrBeacType query( double lon, double lat, double elev );
+};
+
+
+extern FGMarkerBeacons *current_beacons;
+
+
+#endif // _FG_MKRBEACON_HXX
projects / flightgear.git / commitdiff