src/ATC/approach.cxx

   1 // FGApproach - a class to provide approach control at larger airports.
   2 //
   3 // Written by Alexander Kappes, started March 2002.
   4 //
   5 // Copyright (C) 2002  Alexander Kappes
   6 //
   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.
  11 //
  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.
  16 //
  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.
  20
  21 #include "approach.hxx"
  22 #include "transmission.hxx"
  23 #include "transmissionlist.hxx"
  24 #include "ATCdisplay.hxx"
  25 #include "ATCDialog.hxx"
  26
  27 #include <Airports/runways.hxx>
  28 #include <simgear/misc/sg_path.hxx>
  29
  30 #ifdef FG_WEATHERCM
  31 # include <WeatherCM/FGLocalWeatherDatabase.h>
  32 #else
  33 # include <Environment/environment_mgr.hxx>
  34 # include <Environment/environment.hxx>
  35 #endif
  36
  37
  38 #include <GUI/gui.h>
  39
  40 //Constructor
  41 FGApproach::FGApproach(){
  42   comm1_node = fgGetNode("/radios/comm[0]/frequencies/selected-mhz", true);
  43   comm2_node = fgGetNode("/radios/comm[1]/frequencies/selected-mhz", true);
  44
  45   num_planes = 0;
  46   lon_node   = fgGetNode("/position/longitude-deg", true);
  47   lat_node   = fgGetNode("/position/latitude-deg", true);
  48   elev_node  = fgGetNode("/position/altitude-ft", true);
  49   hdg_node   = fgGetNode("/orientation/heading-deg", true);
  50   speed_node = fgGetNode("/velocities/airspeed-kt", true);
  51   etime_node = fgGetNode("/sim/time/elapsed-ms", true);
  52
  53   first = true;
  54   active_runway = "";
  55   int i;
  56   for ( i=0; i<max_planes; i++) {
  57     planes[i].contact   = 0;
  58     planes[i].wpn       = 0;
  59     planes[i].dnwp      = -999.;
  60     planes[i].on_crs    = true;
  61     planes[i].turn_rate = 10.0;
  62     planes[i].desc_rate = 1000.0;
  63     planes[i].clmb_rate = 500.0;
  64     planes[i].tlm       = 0.0;
  65     planes[i].lmc.c1    = 0;
  66     planes[i].lmc.c2    = 0;
  67     planes[i].lmc.c3    = -1;
  68     planes[i].wp_change = false;
  69   }
  70 }
  71
  72 //Destructor
  73 FGApproach::~FGApproach(){
  74 }
  75
  76 void FGApproach::Init() {
  77   display = false;
  78 }
  79
  80
  81
  82 // ============================================================================
  83 // the main update function
  84 // ============================================================================
  85 void FGApproach::Update(double dt) {
  86
  87         const int max_trans = 20;
  88         FGTransmission tmissions[max_trans];
  89         int    wpn;
  90         int    station = 1;
  91         TransCode code;
  92         TransPar TPar;
  93         int    i,j;
  94         //double course, d,
  95         double adif, datp;
  96         //char   buf[10];
  97         string message;
  98         //static string atcmsg1[10];
  99         //static string atcmsg2[10];
 100         string mentry;
 101         string transm;
 102         TransPar tpars;
 103         //static bool TransDisplayed = false;
 104
 105         update_plane_dat();
 106         if ( active_runway == "" ) get_active_runway();
 107
 108         double comm1_freq = comm1_node->getDoubleValue();
 109
 110         //bool DisplayTransmissions = true;
 111
 112         for (i=0; i<num_planes; i++) {
 113                 if ( planes[i].ident == "Player") {
 114                         station = 1;
 115                         tpars.station = name;
 116                         tpars.callsign = "Player";
 117                         tpars.airport = ident;
 118
 119                         //cout << "ident = " << ident << " name = " << name << '\n';
 120
 121                         int num_trans = 0;
 122                         // is the frequency of the station tuned in?
 123                         if ( freq == (int)(comm1_freq*100.0 + 0.5) ) {
 124                                 current_transmissionlist->query_station( station, tmissions, max_trans, num_trans );
 125                                 // loop over all transmissions for station
 126                                 for ( j=0; j<=num_trans-1; j++ ) {
 127                                         code = tmissions[j].get_code();
 128                                         // select proper transmissions
 129                                         if ( ( code.c2 == -1 && planes[i].lmc.c3 == 0 ) ||
 130                                                 ( code.c1 == 0  && code.c2 == planes[i].lmc.c2 ) ) {
 131                                                 mentry = current_transmissionlist->gen_text(station, code, tpars, false);
 132                                                 transm = current_transmissionlist->gen_text(station, code, tpars, true);
 133                                                 // is the transmission already registered?
 134                                                 if (!current_atcdialog->trans_reg( ident, transm )) {
 135                                                         current_atcdialog->add_entry( ident, transm, mentry );
 136                                                 }
 137                                         }
 138                                 }
 139                         }
 140                 }
 141         }
 142
 143         for ( i=0; i<num_planes; i++ ) {
 144                 //cout << "TPar.airport = " << TPar.airport << " TPar.station = " << TPar.station << " TPar.callsign = " << TPar.callsign << '\n';
 145                 //if ( planes[i].ident == TPar.callsign && name == TPar.airport && TPar.station == "approach" ) {
 146                         //if ( TPar.request && TPar.intention == "landing" && ident == TPar.intid) {
 147                         if(planes[i].ident == "Player" && fgGetBool("/sim/atc/opt0")) {
 148                                 //cout << "Landing requested\n";
 149                                 fgSetBool("/sim/atc/opt0", false);
 150                                 planes[i].wpn = 0;
 151                                 // ===========================
 152                                 // === calculate waypoints ===
 153                                 // ===========================
 154                                 calc_wp( i );
 155                                 update_param( i );
 156                                 wpn = planes[i].wpn-1;
 157                                 planes[i].aalt = planes[i].wpts[wpn-1][2];
 158                                 planes[i].ahdg = planes[i].wpts[wpn][4];
 159
 160                                 // generate the message
 161                                 code.c1 = 1;
 162                                 code.c2 = 1;
 163                                 code.c3 = 0;
 164                                 adif = angle_diff_deg( planes[i].hdg, planes[i].ahdg );
 165                                 tpars.station = name;
 166                                 tpars.callsign = "Player";
 167                                 if ( adif < 0 ) tpars.tdir = 1;
 168                                 else            tpars.tdir = 2;
 169                                 tpars.heading = planes[i].ahdg;
 170                                 if      (planes[i].alt-planes[i].aalt > 100.0)  tpars.VDir = 1;
 171                                 else if (planes[i].alt-planes[i].aalt < -100.0) tpars.VDir = 3;
 172                                 else tpars.VDir = 2;
 173                                 tpars.alt = planes[i].aalt;
 174                                 message = current_transmissionlist->gen_text(station, code, tpars, true );
 175                                 //cout << message << '\n';
 176                                 globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 177                                 planes[i].lmc = code;
 178                                 planes[i].tlm = etime_node->getDoubleValue();
 179                                 planes[i].on_crs = true;
 180                                 planes[i].contact = 1;
 181                         }
 182                 //}
 183
 184                 //if(1) {
 185                 if ( planes[i].contact == 1 ) {
 186                         // =========================
 187                         // === update parameters ===
 188                         // =========================
 189                         update_param( i );
 190                         //cout << planes[i].brg << " " << planes[i].dist << " " << planes[i].wpts[wpn+1][0]
 191                         //<< " " << planes[i].wpts[wpn+1][1] << " " << planes[i].wpts[wpn+1][4]
 192                         //cout << wpn << " distance to current course = " << planes[i].dcc << endl;
 193                         //cout << etime_node->getDoubleValue() << endl;
 194
 195                         // =========================
 196                         // === reached waypoint? ===
 197                         // =========================
 198                         wpn = planes[i].wpn-2;
 199                         adif = angle_diff_deg( planes[i].hdg, planes[i].wpts[wpn][4] )
 200                         * SGD_DEGREES_TO_RADIANS;
 201                         datp = 2*sin(fabs(adif)/2.0)*sin(fabs(adif)/2.0) *
 202                                planes[i].spd/3600. * planes[i].turn_rate +
 203                                planes[i].spd/3600. * 3.0;
 204                         //cout << adif/SGD_DEGREES_TO_RADIANS << " "
 205                         //     << datp << " " << planes[i].dnc << " " << planes[i].dcc <<endl;
 206                         if ( fabs(planes[i].dnc) < datp ) {
 207                         //if ( fabs(planes[i].dnc) < 0.3 && planes[i].dnwp < 1.0 ) {
 208                                 //cout << "Reached next waypoint!\n";
 209                                 planes[i].wpn -= 1;
 210                                 wpn = planes[i].wpn-1;
 211                                 planes[i].ahdg = planes[i].wpts[wpn][4];
 212                                 planes[i].aalt = planes[i].wpts[wpn-1][2];
 213                                 planes[i].wp_change = true;
 214
 215                                 // generate the message
 216                                 adif = angle_diff_deg( planes[i].hdg, planes[i].ahdg );
 217                                 tpars.station = name;
 218                                 tpars.callsign = "Player";
 219                                 if ( adif < 0 ) tpars.tdir = 1;
 220                                 else            tpars.tdir = 2;
 221                                 tpars.heading = planes[i].ahdg;
 222
 223                                 if ( wpn-1 != 0) {
 224                                         code.c1 = 1;
 225                                         code.c2 = 1;
 226                                         code.c3 = 0;
 227                                         if      (planes[i].alt-planes[i].aalt > 100.0)  tpars.VDir = 1;
 228                                         else if (planes[i].alt-planes[i].aalt < -100.0) tpars.VDir = 3;
 229                                         else tpars.VDir = 2;
 230                                         tpars.alt = planes[i].aalt;
 231                                         message = current_transmissionlist->gen_text(station, code, tpars, true );
 232                                         //cout << "Approach transmitting...\n";
 233                                         //cout << message << '\n';
 234                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 235
 236                                 }
 237                                 else {
 238                                         code.c1 = 1;
 239                                         code.c2 = 3;
 240                                         code.c3 = 0;
 241                                         tpars.runway = active_runway;
 242                                         message = current_transmissionlist->gen_text(station, code, tpars, true);
 243                                         //cout << "Approach transmitting 2 ...\n";
 244                                         //cout << message << '\n';
 245                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 246                                 }
 247                                 planes[i].lmc = code;
 248                                 planes[i].tlm = etime_node->getDoubleValue();
 249                                 planes[i].on_crs = true;
 250
 251                                 update_param( i );
 252                         }
 253
 254                         // =========================
 255                         // === come off course ? ===
 256                         // =========================
 257                         if ( fabs(planes[i].dcc) > 1.0 &&
 258                            ( !planes[i].wp_change || etime_node->getDoubleValue() - planes[i].tlm > tbm ) ) {
 259                                 //cout << "Off course!\n";
 260                                 if ( planes[i].on_crs ) {
 261                                         if ( planes[i].dcc < 0) {
 262                                                 planes[i].ahdg += 30.0;
 263                                         }
 264                                         else {
 265                                                 planes[i].ahdg -= 30.0;
 266                                         }
 267                                         if (planes[i].ahdg > 360.0) planes[i].ahdg -= 360.0;
 268                                         else if (planes[i].ahdg < 0.0) planes[i].ahdg += 360.0;
 269                                 }
 270                                 //cout << planes[i].on_crs << " "
 271                                 //     << angle_diff_deg( planes[i].hdg, planes[i].ahdg) << " "
 272                                 //     << etime_node->getDoubleValue() << " "
 273                                 //     << planes[i].tlm << endl;
 274                                 // generate the message
 275                                 if ( planes[i].on_crs ||
 276                                    ( fabs(angle_diff_deg( planes[i].hdg, planes[i].ahdg )) >  30.0  &&
 277                                     etime_node->getDoubleValue() - planes[i].tlm > tbm) ) {
 278                                         // generate the message
 279                                         code.c1 = 1;
 280                                         code.c2 = 4;
 281                                         code.c3 = 0;
 282                                         adif = angle_diff_deg( planes[i].hdg, planes[i].ahdg );
 283                                         tpars.station = name;
 284                                         tpars.callsign = "Player";
 285                                         tpars.miles   = fabs(planes[i].dcc);
 286                                         if ( adif < 0 ) tpars.tdir = 1;
 287                                         else            tpars.tdir = 2;
 288                                         tpars.heading = planes[i].ahdg;
 289                                         message = current_transmissionlist->gen_text(station, code, tpars, true);
 290                                         //cout << "Approach transmitting 3 ...\n";
 291                                         //cout << message << '\n';
 292                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 293                                         planes[i].lmc = code;
 294                                         planes[i].tlm = etime_node->getDoubleValue();
 295                                 }
 296
 297                                 planes[i].on_crs = false;
 298                         }
 299                         else if ( !planes[i].on_crs ) {
 300                                 //cout << "Off course 2!\n";
 301                                 wpn = planes[i].wpn-1;
 302                                 adif = angle_diff_deg( planes[i].hdg, planes[i].wpts[wpn][4] )
 303                                        * SGD_DEGREES_TO_RADIANS;
 304                                 datp = 2*sin(fabs(adif)/2.0)*sin(fabs(adif)/2.0) *
 305                                 planes[i].spd/3600. * planes[i].turn_rate +
 306                                 planes[i].spd/3600. * 3.0;
 307                                 if ( fabs(planes[i].dcc) < datp ) {
 308                                         planes[i].ahdg = fabs(planes[i].wpts[wpn][4]);
 309
 310                                         // generate the message
 311                                         code.c1 = 1;
 312                                         code.c2 = 2;
 313                                         code.c3 = 0;
 314                                         tpars.station = name;
 315                                         tpars.callsign = "Player";
 316                                         if ( adif < 0 ) tpars.tdir = 1;
 317                                         else            tpars.tdir = 2;
 318                                         tpars.heading = planes[i].ahdg;
 319                                         message = current_transmissionlist->gen_text(station, code, tpars, true);
 320                                         //cout << "Approach transmitting 4 ...\n";
 321                                         //cout << message << '\n';
 322                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 323                                         planes[i].lmc = code;
 324                                         planes[i].tlm = etime_node->getDoubleValue();
 325
 326                                         planes[i].on_crs = true;
 327                                 }
 328                         }
 329                         else if ( planes[i].wp_change  ) {
 330                                 planes[i].wp_change = false;
 331                         }
 332
 333                         // ===================================================================
 334                         // === Less than two minutes away from touchdown? -> Contact Tower ===
 335                         // ===================================================================
 336                         if ( planes[i].wpn == 2 && planes[i].dnwp < planes[i].spd/60.*2.0 ) {
 337
 338                                 double freq = 121.95;   // Hardwired - FIXME
 339                                 // generate message
 340                                 code.c1 = 1;
 341                                 code.c2 = 5;
 342                                 code.c3 = 0;
 343                                 tpars.station = name;
 344                                 tpars.callsign = "Player";
 345                                 tpars.freq    = freq;
 346                                 message = current_transmissionlist->gen_text(station, code, tpars, true);
 347                                 //cout << "Approach transmitting 5 ...\n";
 348                                 //cout << message << '\n';
 349                                 globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 350                                 planes[i].lmc = code;
 351                                 planes[i].tlm = etime_node->getDoubleValue();
 352
 353                                 planes[i].contact = 2;
 354                         }
 355                 }
 356         }
 357 }
 358
 359
 360 // ============================================================================
 361 // update course parameters
 362 // ============================================================================
 363 void FGApproach::update_param( const int &i ) {
 364
 365   double course, d;
 366
 367   int wpn = planes[i].wpn-1;            // this is the current waypoint
 368
 369   planes[i].dcc  = calc_psl_dist(planes[i].brg, planes[i].dist,
 370                                  planes[i].wpts[wpn][0], planes[i].wpts[wpn][1],
 371                                  planes[i].wpts[wpn][4]);
 372   planes[i].dnc  = calc_psl_dist(planes[i].brg, planes[i].dist,
 373                                  planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 374                                  planes[i].wpts[wpn-1][4]);
 375   calc_hd_course_dist(planes[i].brg, planes[i].dist,
 376                       planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 377                       &course, &d);
 378   planes[i].dnwp = d;
 379
 380 }
 381
 382 // ============================================================================
 383 // smallest difference between two angles in degree
 384 // difference is negative if a1 > a2 and positive if a2 > a1
 385 // ===========================================================================
 386 double FGApproach::angle_diff_deg( const double &a1, const double &a2) {
 387
 388   double a3 = a2 - a1;
 389   if (a3 < 180.0) a3 += 360.0;
 390   if (a3 > 180.0) a3 -= 360.0;
 391
 392   return a3;
 393 }
 394
 395 // ============================================================================
 396 // calculate waypoints
 397 // ============================================================================
 398 void FGApproach::calc_wp( const int &i ) {
 399
 400         int j;
 401         double course, d, cd, a1;
 402
 403         int wpn = planes[i].wpn;
 404         // waypoint 0: Threshold of active runway
 405         calc_gc_course_dist(Point3D(lon*SGD_DEGREES_TO_RADIANS, lat*SGD_DEGREES_TO_RADIANS, 0.0),
 406                             Point3D(active_rw_lon*SGD_DEGREES_TO_RADIANS,active_rw_lat*SGD_DEGREES_TO_RADIANS, 0.0 ),
 407                             &course, &d);
 408         double d1 = active_rw_hdg+180.0;
 409         if ( d1 > 360.0 ) d1 -=360.0;
 410         calc_cd_head_dist(360.0-course*SGD_RADIANS_TO_DEGREES, d/SG_NM_TO_METER,
 411                           d1, active_rw_len/SG_NM_TO_METER/2.0,
 412                           &planes[i].wpts[wpn][0], &planes[i].wpts[wpn][1]);
 413         planes[i].wpts[wpn][2] = elev;
 414         planes[i].wpts[wpn][4] = 0.0;
 415         planes[i].wpts[wpn][5] = 0.0;
 416         wpn += 1;
 417
 418         // ======================
 419         // horizontal navigation
 420         // ======================
 421         // waypoint 1: point for turning onto final
 422         calc_cd_head_dist(planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1], d1, lfl,
 423                           &planes[i].wpts[wpn][0], &planes[i].wpts[wpn][1]);
 424         calc_hd_course_dist(planes[i].wpts[wpn][0],   planes[i].wpts[wpn][1],
 425                             planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 426                             &course, &d);
 427         planes[i].wpts[wpn][4] = course;
 428         planes[i].wpts[wpn][5] = d;
 429         wpn += 1;
 430
 431         // calculate course and distance from plane position to waypoint 1
 432         calc_hd_course_dist(planes[i].brg, planes[i].dist, planes[i].wpts[1][0],
 433                             planes[i].wpts[1][1], &course, &d);
 434         // check if airport is not between plane and waypoint 1 and
 435         // DCA to airport on course to waypoint 1 is larger than 10 miles
 436         double zero = 0.0;
 437         if ( fabs(angle_diff_deg( planes[i].wpts[1][0], planes[i].brg  )) < 90.0 ||
 438                 calc_psl_dist( zero, zero, planes[i].brg, planes[i].dist, course ) > 10.0 ) {
 439                 // check if turning angle at waypoint 1 would be > max_ta
 440                 if ( fabs(angle_diff_deg( planes[i].wpts[1][4], course )) > max_ta ) {
 441                         cd = calc_psl_dist(planes[i].brg, planes[i].dist,
 442                              planes[i].wpts[1][0], planes[i].wpts[1][1],
 443                              planes[i].wpts[1][4]);
 444                         a1 = atan2(cd,planes[i].wpts[1][1]);
 445                         planes[i].wpts[wpn][0] = planes[i].wpts[1][0] - a1/SGD_DEGREES_TO_RADIANS;
 446                         if ( planes[i].wpts[wpn][0] < 0.0)   planes[i].wpts[wpn][0] += 360.0;
 447                         if ( planes[i].wpts[wpn][0] > 360.0) planes[i].wpts[wpn][0] -= 360.0;
 448                         planes[i].wpts[wpn][1] = fabs(cd) / sin(fabs(a1));
 449                         calc_hd_course_dist(planes[i].wpts[wpn][0],   planes[i].wpts[wpn][1],
 450                                             planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 451                                             &course, &d);
 452                         planes[i].wpts[wpn][4] = course;
 453                         planes[i].wpts[wpn][5] = d;
 454                         wpn += 1;
 455
 456                         calc_hd_course_dist(planes[i].brg, planes[i].dist, planes[i].wpts[wpn-1][0],
 457                                             planes[i].wpts[wpn-1][1], &course, &d);
 458                 }
 459         } else {
 460                 double leg = 10.0;
 461                 a1 = atan2(planes[i].wpts[1][1], leg );
 462
 463                 if ( angle_diff_deg(planes[i].brg,planes[i].wpts[1][0]) < 0 )
 464                         planes[i].wpts[wpn][0] = planes[i].wpts[1][0] + a1/SGD_DEGREES_TO_RADIANS;
 465                 else planes[i].wpts[wpn][0] = planes[i].wpts[1][0] - a1/SGD_DEGREES_TO_RADIANS;
 466
 467                 planes[i].wpts[wpn][1] = sqrt( planes[i].wpts[1][1]*planes[i].wpts[1][1] + leg*leg );
 468                 calc_hd_course_dist(planes[i].wpts[wpn][0],   planes[i].wpts[wpn][1],
 469                                     planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 470                                     &course, &d);
 471                 planes[i].wpts[wpn][4] = course;
 472                 planes[i].wpts[wpn][5] = d;
 473                 wpn += 1;
 474
 475                 calc_hd_course_dist(planes[i].brg, planes[i].dist,
 476                                     planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 477                                     &course, &d);
 478         }
 479
 480         planes[i].wpts[wpn][0] = planes[i].brg;
 481         planes[i].wpts[wpn][1] = planes[i].dist;
 482         planes[i].wpts[wpn][2] = planes[i].alt;
 483         planes[i].wpts[wpn][4] = course;
 484         planes[i].wpts[wpn][5] = d;
 485         wpn += 1;
 486
 487         planes[i].wpn = wpn;
 488
 489         // Now check if legs are too short or if legs can be shortend
 490         // legs must be at least 2 flight minutes long
 491         double mdist = planes[i].spd / 60.0 * 2.0;
 492         for ( j=2; j<wpn-1; ++j ) {
 493                 if ( planes[i].wpts[j][1] < mdist) {
 494                 }
 495         }
 496
 497         // ====================
 498         // vertical navigation
 499         // ====================
 500         double alt = elev+3000.0;
 501         planes[i].wpts[1][2] = round_alt( true, alt );
 502         for ( j=2; j<wpn-1; ++j ) {
 503                 double dalt = planes[i].alt - planes[i].wpts[j-1][2];
 504                 if ( dalt > 0 ) {
 505                         alt = planes[i].wpts[j-1][2] +
 506                               (planes[i].wpts[j][5] / planes[i].spd) * 60.0 * planes[i].desc_rate;
 507                         planes[i].wpts[j][2] = round_alt( false, alt );
 508                         if ( planes[i].wpts[j][2] > planes[i].alt )
 509                                 planes[i].wpts[j][2] = round_alt( false, planes[i].alt );
 510                 }
 511                 else {
 512                         planes[i].wpts[j][2] = planes[i].wpts[1][2];
 513                 }
 514         }
 515
 516         cout << "Plane position: " << planes[i].brg << " " << planes[i].dist << endl;
 517         for ( j=0; j<wpn; ++j ) {
 518                 cout << "Waypoint " << j << endl;
 519                 cout << "------------------" << endl;
 520                 cout << planes[i].wpts[j][0] << "   " << planes[i].wpts[j][1]
 521                      << "   " << planes[i].wpts[j][2] << "   " << planes[i].wpts[j][5];
 522                 cout << endl << endl;
 523         }
 524
 525 }
 526
 527
 528 // ============================================================================
 529 // round altitude value to next highest/lowest 500 feet
 530 // ============================================================================
 531 double FGApproach::round_alt( const bool hl, double alt ) {
 532
 533   alt = alt/1000.0;
 534   if ( hl ) {
 535     if ( alt > (int)(alt)+0.5 ) alt = ((int)(alt)+1)*1000.0;
 536     else alt = ((int)(alt)+0.5)*1000.0;
 537   }
 538   else {
 539     if ( alt > (int)(alt)+0.5 ) alt = ((int)(alt)+0.5)*1000.0;
 540     else alt = ((int)(alt))*1000.0;
 541   }
 542
 543   return alt;
 544 }
 545
 546
 547 // ============================================================================
 548 // get active runway
 549 // ============================================================================
 550 void FGApproach::get_active_runway() {
 551         //cout << "Entering FGApproach::get_active_runway()\n";
 552
 553 #ifdef FG_WEATHERCM
 554   sgVec3 position = { lat, lon, elev };
 555   FGPhysicalProperty stationweather = WeatherDatabase->get(position);
 556 #else
 557   FGEnvironment stationweather =
 558       ((FGEnvironmentMgr *)globals->get_subsystem("environment"))
 559         ->getEnvironment(lat, lon, elev);
 560 #endif
 561
 562 #ifdef FG_WEATHERCM
 563   //Set the heading to into the wind
 564   double wind_x = stationweather.Wind[0];
 565   double wind_y = stationweather.Wind[1];
 566
 567   double speed = sqrt( wind_x*wind_x + wind_y*wind_y ) * SG_METER_TO_NM / (60.0*60.0);
 568   double hdg;
 569
 570   //If no wind use 270degrees
 571   if(speed == 0) {
 572     hdg = 270;
 573   } else {
 574     // //normalize the wind to get the direction
 575     //wind_x /= speed; wind_y /= speed;
 576
 577     hdg = - atan2 ( wind_x, wind_y ) * SG_RADIANS_TO_DEGREES ;
 578     if (hdg < 0.0)
 579       hdg += 360.0;
 580   }
 581 #else
 582   double hdg = stationweather.get_wind_from_heading_deg();
 583 #endif
 584
 585   FGRunway runway;
 586   if ( globals->get_runways()->search( ident, int(hdg), &runway) ) {
 587     active_runway = runway.rwy_no;
 588     active_rw_hdg = runway.heading;
 589     active_rw_lon = runway.lon;
 590     active_rw_lat = runway.lat;
 591     active_rw_len = runway.length;
 592     //cout << "Active runway is: " << active_runway << "  heading = "
 593     // << active_rw_hdg
 594     // << " lon = " << active_rw_lon
 595     // << " lat = " << active_rw_lat <<endl;
 596   }
 597   else cout << "FGRunways search failed\n";
 598
 599 }
 600
 601 // ========================================================================
 602 // update infos about plane
 603 // ========================================================================
 604 void FGApproach::update_plane_dat() {
 605
 606   //cout << "Update Approach " << ident << "   " << num_planes << " registered" << endl;
 607   // update plane positions
 608   int i;
 609   for (i=0; i<num_planes; i++) {
 610     planes[i].lon = lon_node->getDoubleValue();
 611     planes[i].lat = lat_node->getDoubleValue();
 612     planes[i].alt = elev_node->getDoubleValue();
 613     planes[i].hdg = hdg_node->getDoubleValue();
 614     planes[i].spd = speed_node->getDoubleValue();
 615
 616     /*Point3D aircraft = sgGeodToCart( Point3D(planes[i].lon*SGD_DEGREES_TO_RADIANS,
 617                                              planes[i].lat*SGD_DEGREES_TO_RADIANS,
 618                                              planes[i].alt*SG_FEET_TO_METER) );*/
 619     double course, distance;
 620     calc_gc_course_dist(Point3D(lon*SGD_DEGREES_TO_RADIANS, lat*SGD_DEGREES_TO_RADIANS, 0.0),
 621                         Point3D(planes[i].lon*SGD_DEGREES_TO_RADIANS,planes[i].lat*SGD_DEGREES_TO_RADIANS, 0.0 ),
 622                         &course, &distance);
 623     planes[i].dist = distance/SG_NM_TO_METER;
 624     planes[i].brg  = 360.0-course*SGD_RADIANS_TO_DEGREES;
 625
 626     //cout << "Plane Id: " << planes[i].ident << "  Distance to " << ident
 627     // << " is " << planes[i].dist << " miles   " << "Bearing " << planes[i].brg << endl;
 628
 629   }
 630 }
 631
 632 // =======================================================================
 633 // Add plane to Approach list
 634 // =======================================================================
 635 void FGApproach::AddPlane(string pid) {
 636
 637   int i;
 638   for ( i=0; i<num_planes; i++) {
 639     if ( planes[i].ident == pid) {
 640       //cout << "Plane already registered: " << planes[i].ident << ' ' << ident << ' ' << num_planes << endl;
 641       return;
 642     }
 643   }
 644   planes[num_planes].ident = pid;
 645   ++num_planes;
 646   //cout << "Plane added to list: " << ident << " " << num_planes << endl;
 647   return;
 648 }
 649
 650 // ================================================================================
 651 // closest distance between a point (h1,d1) and a straigt line (h2,d2,h3) in 2 dim.
 652 // ================================================================================
 653 double FGApproach::calc_psl_dist(const double &h1, const double &d1,
 654                                  const double &h2, const double &d2,
 655                                  const double &h3)
 656 {
 657   double a1 = h1 * SGD_DEGREES_TO_RADIANS;
 658   double a2 = h2 * SGD_DEGREES_TO_RADIANS;
 659   double a3 = h3 * SGD_DEGREES_TO_RADIANS;
 660   double x1 = cos(a1) * d1;
 661   double y1 = sin(a1) * d1;
 662   double x2 = cos(a2) * d2;
 663   double y2 = sin(a2) * d2;
 664   double x3 = cos(a3);
 665   double y3 = sin(a3);
 666
 667   // formula: dis = sqrt( (v1-v2)**2 - ((v1-v2)*v3)**2 ); vi = (xi,yi)
 668   double val1   = (x1-x2)*(x1-x2) + (y1-y2)*(y1-y2);
 669   double val2   = ((x1-x2)*x3 + (y1-y2)*y3) * ((x1-x2)*x3 + (y1-y2)*y3);
 670   double dis    = val1 - val2;
 671   // now get sign for offset
 672   //cout << x1 << " " << x2 << " " << y1 << " " << y2 << " "
 673   //     << x3 << " " << y3 << " "
 674   //     << val1 << " " << val2 << " " << dis << endl;
 675   x3 *= sqrt(val2);
 676   y3 *= sqrt(val2);
 677   double da = fabs(atan2(y3,x3) - atan2(y1-y2,x1-x2));
 678   if ( da > SGD_PI ) da -= 2*SGD_PI;
 679   if ( fabs(da) > SGD_PI/2.) {
 680     //if ( x3*(x1-x2) < 0.0 && y3*(y1-y2) < 0.0) {
 681     x3 *= -1.0;
 682     y3 *= -1.0;
 683   }
 684   //cout << x3 << " " << y3 << endl;
 685   double dis1   = x1-x2-x3;
 686   double dis2   = y1-y2-y3;
 687   dis = sqrt(dis);
 688   da = atan2(dis2,dis1);
 689   if ( da < 0.0 ) da  += 2*SGD_PI;
 690   if ( da < a3 )  dis *= -1.0;
 691   //cout << dis1 << " " << dis2 << " " << da*SGD_RADIANS_TO_DEGREES << " " << h3
 692   //     << " " << sqrt(dis1*dis1 + dis2*dis2) << " " << dis << endl;
 693   //cout << atan2(dis2,dis1)*SGD_RADIANS_TO_DEGREES << " " << dis << endl;
 694
 695   return dis;
 696 }
 697
 698
 699 // ========================================================================
 700 // Calculate new bear/dist given starting bear/dis, and offset radial,
 701 // and distance.
 702 // ========================================================================
 703 void FGApproach::calc_cd_head_dist(const double &h1, const double &d1,
 704                                    const double &course, const double &dist,
 705                                    double *h2, double *d2)
 706 {
 707   double a1 = h1 * SGD_DEGREES_TO_RADIANS;
 708   double a2 = course * SGD_DEGREES_TO_RADIANS;
 709   double x1 = cos(a1) * d1;
 710   double y1 = sin(a1) * d1;
 711   double x2 = cos(a2) * dist;
 712   double y2 = sin(a2) * dist;
 713
 714   *d2 = sqrt((x1+x2)*(x1+x2) + (y1+y2)*(y1+y2));
 715   *h2 = atan2( (y1+y2), (x1+x2) ) * SGD_RADIANS_TO_DEGREES;
 716   if ( *h2 < 0 ) *h2 = *h2+360;
 717 }
 718
 719
 720
 721 // ========================================================================
 722 // get heading and distance between two points; point1 ---> point2
 723 // ========================================================================
 724 void FGApproach::calc_hd_course_dist(const double &h1, const double &d1,
 725                                      const double &h2, const double &d2,
 726                                      double *course, double *dist)
 727 {
 728   double a1 = h1 * SGD_DEGREES_TO_RADIANS;
 729   double a2 = h2 * SGD_DEGREES_TO_RADIANS;
 730   double x1 = cos(a1) * d1;
 731   double y1 = sin(a1) * d1;
 732   double x2 = cos(a2) * d2;
 733   double y2 = sin(a2) * d2;
 734
 735   *dist   = sqrt( (y2-y1)*(y2-y1) + (x2-x1)*(x2-x1) );
 736   *course = atan2( (y2-y1), (x2-x1) ) * SGD_RADIANS_TO_DEGREES;
 737   if ( *course < 0 ) *course = *course+360;
 738   //cout << x1 << " " << y1 << " " << x2 << " " << y2 << " " << *dist << " " << *course << endl;
 739 }
 740
 741
 742
 743 int FGApproach::RemovePlane() {
 744
 745   // first check if anything has to be done
 746   bool rmplane = false;
 747   int i;
 748
 749   for (i=0; i<num_planes; i++) {
 750     if (planes[i].dist > range*SG_NM_TO_METER) {
 751       rmplane = true;
 752       break;
 753     }
 754   }
 755   if (!rmplane) return num_planes;
 756
 757   // now make a copy of the plane list
 758   PlaneApp tmp[max_planes];
 759   for (i=0; i<num_planes; i++) {
 760     tmp[i] = planes[i];
 761   }
 762
 763   int np = 0;
 764   // now check which planes are still in range
 765   for (i=0; i<num_planes; i++) {
 766     if (tmp[i].dist <= range*SG_NM_TO_METER) {
 767       planes[np] = tmp[i];
 768       np += 1;
 769     }
 770   }
 771   num_planes = np;
 772
 773   return num_planes;
 774 }