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         atc_type station = APPROACH;
  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 = APPROACH;
 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                                         //cout << "code is " << code.c1 << "  " << code.c2 << "  " << code.c3 << '\n';
 129                                         // select proper transmissions
 130                                         if(code.c3 != 2) {    // DCL - hack to prevent request crossing airspace being displayed since this isn't implemented yet.
 131                                             if ( ( code.c2 == -1 && planes[i].lmc.c3 == 0 ) ||
 132                                                     ( code.c1 == 0  && code.c2 == planes[i].lmc.c2 ) ) {
 133                                                     mentry = current_transmissionlist->gen_text(station, code, tpars, false);
 134                                                     transm = current_transmissionlist->gen_text(station, code, tpars, true);
 135                                                     // is the transmission already registered?
 136                                                     if (!current_atcdialog->trans_reg( ident, transm, APPROACH )) {
 137                                                             current_atcdialog->add_entry( ident, transm, mentry, APPROACH, 0 );
 138                                                     }
 139                                             }
 140                                         }
 141                                 }
 142                         }
 143                 }
 144         }
 145
 146         for ( i=0; i<num_planes; i++ ) {
 147                 //cout << "TPar.airport = " << TPar.airport << " TPar.station = " << TPar.station << " TPar.callsign = " << TPar.callsign << '\n';
 148                 //if ( planes[i].ident == TPar.callsign && name == TPar.airport && TPar.station == "approach" ) {
 149                         //if ( TPar.request && TPar.intention == "landing" && ident == TPar.intid) {
 150                         if(planes[i].ident == "Player" && fgGetBool("/sim/atc/opt0")) {
 151                                 //cout << "Landing requested\n";
 152                                 fgSetBool("/sim/atc/opt0", false);
 153                                 planes[i].wpn = 0;
 154                                 // ===========================
 155                                 // === calculate waypoints ===
 156                                 // ===========================
 157                                 calc_wp( i );
 158                                 update_param( i );
 159                                 wpn = planes[i].wpn-1;
 160                                 planes[i].aalt = planes[i].wpts[wpn-1][2];
 161                                 planes[i].ahdg = planes[i].wpts[wpn][4];
 162
 163                                 // generate the message
 164                                 code.c1 = 1;
 165                                 code.c2 = 1;
 166                                 code.c3 = 0;
 167                                 adif = angle_diff_deg( planes[i].hdg, planes[i].ahdg );
 168                                 tpars.station = name;
 169                                 tpars.callsign = "Player";
 170                                 if ( adif < 0 ) tpars.tdir = 1;
 171                                 else            tpars.tdir = 2;
 172                                 tpars.heading = planes[i].ahdg;
 173                                 if      (planes[i].alt-planes[i].aalt > 100.0)  tpars.VDir = 1;
 174                                 else if (planes[i].alt-planes[i].aalt < -100.0) tpars.VDir = 3;
 175                                 else tpars.VDir = 2;
 176                                 tpars.alt = planes[i].aalt;
 177                                 message = current_transmissionlist->gen_text(station, code, tpars, true );
 178                                 //cout << message << '\n';
 179                                 globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 180                                 planes[i].lmc = code;
 181                                 planes[i].tlm = etime_node->getDoubleValue();
 182                                 planes[i].on_crs = true;
 183                                 planes[i].contact = 1;
 184                         }
 185                 //}
 186
 187                 //if(1) {
 188                 if ( planes[i].contact == 1 ) {
 189                         // =========================
 190                         // === update parameters ===
 191                         // =========================
 192                         update_param( i );
 193                         //cout << planes[i].brg << " " << planes[i].dist << " " << planes[i].wpts[wpn+1][0]
 194                         //<< " " << planes[i].wpts[wpn+1][1] << " " << planes[i].wpts[wpn+1][4]
 195                         //cout << wpn << " distance to current course = " << planes[i].dcc << endl;
 196                         //cout << etime_node->getDoubleValue() << endl;
 197
 198                         // =========================
 199                         // === reached waypoint? ===
 200                         // =========================
 201                         wpn = planes[i].wpn-2;
 202                         adif = angle_diff_deg( planes[i].hdg, planes[i].wpts[wpn][4] )
 203                         * SGD_DEGREES_TO_RADIANS;
 204                         datp = 2*sin(fabs(adif)/2.0)*sin(fabs(adif)/2.0) *
 205                                planes[i].spd/3600. * planes[i].turn_rate +
 206                                planes[i].spd/3600. * 3.0;
 207                         //cout << adif/SGD_DEGREES_TO_RADIANS << " "
 208                         //     << datp << " " << planes[i].dnc << " " << planes[i].dcc <<endl;
 209                         if ( fabs(planes[i].dnc) < datp ) {
 210                         //if ( fabs(planes[i].dnc) < 0.3 && planes[i].dnwp < 1.0 ) {
 211                                 //cout << "Reached next waypoint!\n";
 212                                 planes[i].wpn -= 1;
 213                                 wpn = planes[i].wpn-1;
 214                                 planes[i].ahdg = planes[i].wpts[wpn][4];
 215                                 planes[i].aalt = planes[i].wpts[wpn-1][2];
 216                                 planes[i].wp_change = true;
 217
 218                                 // generate the message
 219                                 adif = angle_diff_deg( planes[i].hdg, planes[i].ahdg );
 220                                 tpars.station = name;
 221                                 tpars.callsign = "Player";
 222                                 if ( adif < 0 ) tpars.tdir = 1;
 223                                 else            tpars.tdir = 2;
 224                                 tpars.heading = planes[i].ahdg;
 225
 226                                 if ( wpn-1 != 0) {
 227                                         code.c1 = 1;
 228                                         code.c2 = 1;
 229                                         code.c3 = 0;
 230                                         if      (planes[i].alt-planes[i].aalt > 100.0)  tpars.VDir = 1;
 231                                         else if (planes[i].alt-planes[i].aalt < -100.0) tpars.VDir = 3;
 232                                         else tpars.VDir = 2;
 233                                         tpars.alt = planes[i].aalt;
 234                                         message = current_transmissionlist->gen_text(station, code, tpars, true );
 235                                         //cout << "Approach transmitting...\n";
 236                                         //cout << message << endl;
 237                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 238
 239                                 }
 240                                 else {
 241                                         code.c1 = 1;
 242                                         code.c2 = 3;
 243                                         code.c3 = 0;
 244                                         tpars.runway = active_runway;
 245                                         message = current_transmissionlist->gen_text(station, code, tpars, true);
 246                                         //cout << "Approach transmitting 2 ...\n";
 247                                         //cout << message << endl;
 248                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 249                                 }
 250                                 planes[i].lmc = code;
 251                                 planes[i].tlm = etime_node->getDoubleValue();
 252                                 planes[i].on_crs = true;
 253
 254                                 update_param( i );
 255                         }
 256
 257                         // =========================
 258                         // === come off course ? ===
 259                         // =========================
 260                         if ( fabs(planes[i].dcc) > 1.0 &&
 261                            ( !planes[i].wp_change || etime_node->getDoubleValue() - planes[i].tlm > tbm ) ) {
 262                                 //cout << "Off course!\n";
 263                                 if ( planes[i].on_crs ) {
 264                                         if ( planes[i].dcc < 0) {
 265                                                 planes[i].ahdg += 30.0;
 266                                         }
 267                                         else {
 268                                                 planes[i].ahdg -= 30.0;
 269                                         }
 270                                         if (planes[i].ahdg > 360.0) planes[i].ahdg -= 360.0;
 271                                         else if (planes[i].ahdg < 0.0) planes[i].ahdg += 360.0;
 272                                 }
 273                                 //cout << planes[i].on_crs << " "
 274                                 //     << angle_diff_deg( planes[i].hdg, planes[i].ahdg) << " "
 275                                 //     << etime_node->getDoubleValue() << " "
 276                                 //     << planes[i].tlm << endl;
 277                                 // generate the message
 278                                 if ( planes[i].on_crs ||
 279                                    ( fabs(angle_diff_deg( planes[i].hdg, planes[i].ahdg )) >  30.0  &&
 280                                     etime_node->getDoubleValue() - planes[i].tlm > tbm) ) {
 281                                         // generate the message
 282                                         code.c1 = 1;
 283                                         code.c2 = 4;
 284                                         code.c3 = 0;
 285                                         adif = angle_diff_deg( planes[i].hdg, planes[i].ahdg );
 286                                         tpars.station = name;
 287                                         tpars.callsign = "Player";
 288                                         tpars.miles   = fabs(planes[i].dcc);
 289                                         if ( adif < 0 ) tpars.tdir = 1;
 290                                         else            tpars.tdir = 2;
 291                                         tpars.heading = planes[i].ahdg;
 292                                         message = current_transmissionlist->gen_text(station, code, tpars, true);
 293                                         //cout << "Approach transmitting 3 ...\n";
 294                                         //cout << message << '\n';
 295                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 296                                         planes[i].lmc = code;
 297                                         planes[i].tlm = etime_node->getDoubleValue();
 298                                 }
 299
 300                                 planes[i].on_crs = false;
 301                         }
 302                         else if ( !planes[i].on_crs ) {
 303                                 //cout << "Off course 2!\n";
 304                                 wpn = planes[i].wpn-1;
 305                                 adif = angle_diff_deg( planes[i].hdg, planes[i].wpts[wpn][4] )
 306                                        * SGD_DEGREES_TO_RADIANS;
 307                                 datp = 2*sin(fabs(adif)/2.0)*sin(fabs(adif)/2.0) *
 308                                 planes[i].spd/3600. * planes[i].turn_rate +
 309                                 planes[i].spd/3600. * 3.0;
 310                                 if ( fabs(planes[i].dcc) < datp ) {
 311                                         planes[i].ahdg = fabs(planes[i].wpts[wpn][4]);
 312
 313                                         // generate the message
 314                                         code.c1 = 1;
 315                                         code.c2 = 2;
 316                                         code.c3 = 0;
 317                                         tpars.station = name;
 318                                         tpars.callsign = "Player";
 319                                         if ( adif < 0 ) tpars.tdir = 1;
 320                                         else            tpars.tdir = 2;
 321                                         tpars.heading = planes[i].ahdg;
 322                                         message = current_transmissionlist->gen_text(station, code, tpars, true);
 323                                         //cout << "Approach transmitting 4 ...\n";
 324                                         //cout << message << '\n';
 325                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 326                                         planes[i].lmc = code;
 327                                         planes[i].tlm = etime_node->getDoubleValue();
 328
 329                                         planes[i].on_crs = true;
 330                                 }
 331                         }
 332                         else if ( planes[i].wp_change  ) {
 333                                 planes[i].wp_change = false;
 334                         }
 335
 336                         // ===================================================================
 337                         // === Less than two minutes away from touchdown? -> Contact Tower ===
 338                         // ===================================================================
 339                         if ( planes[i].wpn == 2 && planes[i].dnwp < planes[i].spd/60.*2.0 ) {
 340
 341                                 double freq = 121.95;   // Hardwired - FIXME
 342                                 // generate message
 343                                 code.c1 = 1;
 344                                 code.c2 = 5;
 345                                 code.c3 = 0;
 346                                 tpars.station = name;
 347                                 tpars.callsign = "Player";
 348                                 tpars.freq    = freq;
 349                                 message = current_transmissionlist->gen_text(station, code, tpars, true);
 350                                 //cout << "Approach transmitting 5 ...\n";
 351                                 //cout << message << '\n';
 352                                 globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 353                                 planes[i].lmc = code;
 354                                 planes[i].tlm = etime_node->getDoubleValue();
 355
 356                                 planes[i].contact = 2;
 357                         }
 358                 }
 359         }
 360 }
 361
 362
 363 // ============================================================================
 364 // update course parameters
 365 // ============================================================================
 366 void FGApproach::update_param( const int &i ) {
 367
 368   double course, d;
 369
 370   int wpn = planes[i].wpn-1;            // this is the current waypoint
 371
 372   planes[i].dcc  = calc_psl_dist(planes[i].brg, planes[i].dist,
 373                                  planes[i].wpts[wpn][0], planes[i].wpts[wpn][1],
 374                                  planes[i].wpts[wpn][4]);
 375   planes[i].dnc  = calc_psl_dist(planes[i].brg, planes[i].dist,
 376                                  planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 377                                  planes[i].wpts[wpn-1][4]);
 378   calc_hd_course_dist(planes[i].brg, planes[i].dist,
 379                       planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 380                       &course, &d);
 381   planes[i].dnwp = d;
 382
 383 }
 384
 385 // ============================================================================
 386 // smallest difference between two angles in degree
 387 // difference is negative if a1 > a2 and positive if a2 > a1
 388 // ===========================================================================
 389 double FGApproach::angle_diff_deg( const double &a1, const double &a2) {
 390
 391   double a3 = a2 - a1;
 392   if (a3 < 180.0) a3 += 360.0;
 393   if (a3 > 180.0) a3 -= 360.0;
 394
 395   return a3;
 396 }
 397
 398 // ============================================================================
 399 // calculate waypoints
 400 // ============================================================================
 401 void FGApproach::calc_wp( const int &i ) {
 402
 403         int j;
 404         double course, d, cd, a1;
 405
 406         int wpn = planes[i].wpn;
 407         // waypoint 0: Threshold of active runway
 408         calc_gc_course_dist(Point3D(lon*SGD_DEGREES_TO_RADIANS, lat*SGD_DEGREES_TO_RADIANS, 0.0),
 409                             Point3D(active_rw_lon*SGD_DEGREES_TO_RADIANS,active_rw_lat*SGD_DEGREES_TO_RADIANS, 0.0 ),
 410                             &course, &d);
 411         double d1 = active_rw_hdg+180.0;
 412         if ( d1 > 360.0 ) d1 -=360.0;
 413         calc_cd_head_dist(360.0-course*SGD_RADIANS_TO_DEGREES, d/SG_NM_TO_METER,
 414                           d1, active_rw_len/SG_NM_TO_METER/2.0,
 415                           &planes[i].wpts[wpn][0], &planes[i].wpts[wpn][1]);
 416         planes[i].wpts[wpn][2] = elev;
 417         planes[i].wpts[wpn][4] = 0.0;
 418         planes[i].wpts[wpn][5] = 0.0;
 419         wpn += 1;
 420
 421         // ======================
 422         // horizontal navigation
 423         // ======================
 424         // waypoint 1: point for turning onto final
 425         calc_cd_head_dist(planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1], d1, lfl,
 426                           &planes[i].wpts[wpn][0], &planes[i].wpts[wpn][1]);
 427         calc_hd_course_dist(planes[i].wpts[wpn][0],   planes[i].wpts[wpn][1],
 428                             planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 429                             &course, &d);
 430         planes[i].wpts[wpn][4] = course;
 431         planes[i].wpts[wpn][5] = d;
 432         wpn += 1;
 433
 434         // calculate course and distance from plane position to waypoint 1
 435         calc_hd_course_dist(planes[i].brg, planes[i].dist, planes[i].wpts[1][0],
 436                             planes[i].wpts[1][1], &course, &d);
 437         // check if airport is not between plane and waypoint 1 and
 438         // DCA to airport on course to waypoint 1 is larger than 10 miles
 439         double zero = 0.0;
 440         if ( fabs(angle_diff_deg( planes[i].wpts[1][0], planes[i].brg  )) < 90.0 ||
 441                 calc_psl_dist( zero, zero, planes[i].brg, planes[i].dist, course ) > 10.0 ) {
 442                 // check if turning angle at waypoint 1 would be > max_ta
 443                 if ( fabs(angle_diff_deg( planes[i].wpts[1][4], course )) > max_ta ) {
 444                         cd = calc_psl_dist(planes[i].brg, planes[i].dist,
 445                              planes[i].wpts[1][0], planes[i].wpts[1][1],
 446                              planes[i].wpts[1][4]);
 447                         a1 = atan2(cd,planes[i].wpts[1][1]);
 448                         planes[i].wpts[wpn][0] = planes[i].wpts[1][0] - a1/SGD_DEGREES_TO_RADIANS;
 449                         if ( planes[i].wpts[wpn][0] < 0.0)   planes[i].wpts[wpn][0] += 360.0;
 450                         if ( planes[i].wpts[wpn][0] > 360.0) planes[i].wpts[wpn][0] -= 360.0;
 451                         planes[i].wpts[wpn][1] = fabs(cd) / sin(fabs(a1));
 452                         calc_hd_course_dist(planes[i].wpts[wpn][0],   planes[i].wpts[wpn][1],
 453                                             planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 454                                             &course, &d);
 455                         planes[i].wpts[wpn][4] = course;
 456                         planes[i].wpts[wpn][5] = d;
 457                         wpn += 1;
 458
 459                         calc_hd_course_dist(planes[i].brg, planes[i].dist, planes[i].wpts[wpn-1][0],
 460                                             planes[i].wpts[wpn-1][1], &course, &d);
 461                 }
 462         } else {
 463                 double leg = 10.0;
 464                 a1 = atan2(planes[i].wpts[1][1], leg );
 465
 466                 if ( angle_diff_deg(planes[i].brg,planes[i].wpts[1][0]) < 0 )
 467                         planes[i].wpts[wpn][0] = planes[i].wpts[1][0] + a1/SGD_DEGREES_TO_RADIANS;
 468                 else planes[i].wpts[wpn][0] = planes[i].wpts[1][0] - a1/SGD_DEGREES_TO_RADIANS;
 469
 470                 planes[i].wpts[wpn][1] = sqrt( planes[i].wpts[1][1]*planes[i].wpts[1][1] + leg*leg );
 471                 calc_hd_course_dist(planes[i].wpts[wpn][0],   planes[i].wpts[wpn][1],
 472                                     planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 473                                     &course, &d);
 474                 planes[i].wpts[wpn][4] = course;
 475                 planes[i].wpts[wpn][5] = d;
 476                 wpn += 1;
 477
 478                 calc_hd_course_dist(planes[i].brg, planes[i].dist,
 479                                     planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 480                                     &course, &d);
 481         }
 482
 483         planes[i].wpts[wpn][0] = planes[i].brg;
 484         planes[i].wpts[wpn][1] = planes[i].dist;
 485         planes[i].wpts[wpn][2] = planes[i].alt;
 486         planes[i].wpts[wpn][4] = course;
 487         planes[i].wpts[wpn][5] = d;
 488         wpn += 1;
 489
 490         planes[i].wpn = wpn;
 491
 492         // Now check if legs are too short or if legs can be shortend
 493         // legs must be at least 2 flight minutes long
 494         double mdist = planes[i].spd / 60.0 * 2.0;
 495         for ( j=2; j<wpn-1; ++j ) {
 496                 if ( planes[i].wpts[j][1] < mdist) {
 497                 }
 498         }
 499
 500         // ====================
 501         // vertical navigation
 502         // ====================
 503         double alt = elev+3000.0;
 504         planes[i].wpts[1][2] = round_alt( true, alt );
 505         for ( j=2; j<wpn-1; ++j ) {
 506                 double dalt = planes[i].alt - planes[i].wpts[j-1][2];
 507                 if ( dalt > 0 ) {
 508                         alt = planes[i].wpts[j-1][2] +
 509                               (planes[i].wpts[j][5] / planes[i].spd) * 60.0 * planes[i].desc_rate;
 510                         planes[i].wpts[j][2] = round_alt( false, alt );
 511                         if ( planes[i].wpts[j][2] > planes[i].alt )
 512                                 planes[i].wpts[j][2] = round_alt( false, planes[i].alt );
 513                 }
 514                 else {
 515                         planes[i].wpts[j][2] = planes[i].wpts[1][2];
 516                 }
 517         }
 518
 519         cout << "Plane position: " << planes[i].brg << " " << planes[i].dist << endl;
 520         for ( j=0; j<wpn; ++j ) {
 521                 cout << "Waypoint " << j << endl;
 522                 cout << "------------------" << endl;
 523                 cout << planes[i].wpts[j][0] << "   " << planes[i].wpts[j][1]
 524                      << "   " << planes[i].wpts[j][2] << "   " << planes[i].wpts[j][5];
 525                 cout << endl << endl;
 526         }
 527
 528 }
 529
 530
 531 // ============================================================================
 532 // round altitude value to next highest/lowest 500 feet
 533 // ============================================================================
 534 double FGApproach::round_alt( const bool hl, double alt ) {
 535
 536   alt = alt/1000.0;
 537   if ( hl ) {
 538     if ( alt > (int)(alt)+0.5 ) alt = ((int)(alt)+1)*1000.0;
 539     else alt = ((int)(alt)+0.5)*1000.0;
 540   }
 541   else {
 542     if ( alt > (int)(alt)+0.5 ) alt = ((int)(alt)+0.5)*1000.0;
 543     else alt = ((int)(alt))*1000.0;
 544   }
 545
 546   return alt;
 547 }
 548
 549
 550 // ============================================================================
 551 // get active runway
 552 // ============================================================================
 553 void FGApproach::get_active_runway() {
 554         //cout << "Entering FGApproach::get_active_runway()\n";
 555
 556 #ifdef FG_WEATHERCM
 557   sgVec3 position = { lat, lon, elev };
 558   FGPhysicalProperty stationweather = WeatherDatabase->get(position);
 559 #else
 560   FGEnvironment stationweather =
 561       ((FGEnvironmentMgr *)globals->get_subsystem("environment"))
 562         ->getEnvironment(lat, lon, elev);
 563 #endif
 564
 565 #ifdef FG_WEATHERCM
 566   //Set the heading to into the wind
 567   double wind_x = stationweather.Wind[0];
 568   double wind_y = stationweather.Wind[1];
 569
 570   double speed = sqrt( wind_x*wind_x + wind_y*wind_y ) * SG_METER_TO_NM / (60.0*60.0);
 571   double hdg;
 572
 573   //If no wind use 270degrees
 574   if(speed == 0) {
 575     hdg = 270;
 576   } else {
 577     // //normalize the wind to get the direction
 578     //wind_x /= speed; wind_y /= speed;
 579
 580     hdg = - atan2 ( wind_x, wind_y ) * SG_RADIANS_TO_DEGREES ;
 581     if (hdg < 0.0)
 582       hdg += 360.0;
 583   }
 584 #else
 585   double hdg = stationweather.get_wind_from_heading_deg();
 586 #endif
 587
 588   FGRunway runway;
 589   if ( globals->get_runways()->search( ident, int(hdg), &runway) ) {
 590     active_runway = runway.rwy_no;
 591     active_rw_hdg = runway.heading;
 592     active_rw_lon = runway.lon;
 593     active_rw_lat = runway.lat;
 594     active_rw_len = runway.length;
 595     //cout << "Active runway is: " << active_runway << "  heading = "
 596     // << active_rw_hdg
 597     // << " lon = " << active_rw_lon
 598     // << " lat = " << active_rw_lat <<endl;
 599   }
 600   else cout << "FGRunways search failed\n";
 601
 602 }
 603
 604 // ========================================================================
 605 // update infos about plane
 606 // ========================================================================
 607 void FGApproach::update_plane_dat() {
 608
 609   //cout << "Update Approach " << ident << "   " << num_planes << " registered" << endl;
 610   // update plane positions
 611   int i;
 612   for (i=0; i<num_planes; i++) {
 613     planes[i].lon = lon_node->getDoubleValue();
 614     planes[i].lat = lat_node->getDoubleValue();
 615     planes[i].alt = elev_node->getDoubleValue();
 616     planes[i].hdg = hdg_node->getDoubleValue();
 617     planes[i].spd = speed_node->getDoubleValue();
 618
 619     /*Point3D aircraft = sgGeodToCart( Point3D(planes[i].lon*SGD_DEGREES_TO_RADIANS,
 620                                              planes[i].lat*SGD_DEGREES_TO_RADIANS,
 621                                              planes[i].alt*SG_FEET_TO_METER) );*/
 622     double course, distance;
 623     calc_gc_course_dist(Point3D(lon*SGD_DEGREES_TO_RADIANS, lat*SGD_DEGREES_TO_RADIANS, 0.0),
 624                         Point3D(planes[i].lon*SGD_DEGREES_TO_RADIANS,planes[i].lat*SGD_DEGREES_TO_RADIANS, 0.0 ),
 625                         &course, &distance);
 626     planes[i].dist = distance/SG_NM_TO_METER;
 627     planes[i].brg  = 360.0-course*SGD_RADIANS_TO_DEGREES;
 628
 629     //cout << "Plane Id: " << planes[i].ident << "  Distance to " << ident
 630     // << " is " << planes[i].dist << " miles   " << "Bearing " << planes[i].brg << endl;
 631
 632   }
 633 }
 634
 635 // =======================================================================
 636 // Add plane to Approach list
 637 // =======================================================================
 638 void FGApproach::AddPlane(string pid) {
 639
 640   int i;
 641   for ( i=0; i<num_planes; i++) {
 642     if ( planes[i].ident == pid) {
 643       //cout << "Plane already registered: " << planes[i].ident << ' ' << ident << ' ' << num_planes << endl;
 644       return;
 645     }
 646   }
 647   planes[num_planes].ident = pid;
 648   ++num_planes;
 649   //cout << "Plane added to list: " << ident << " " << num_planes << endl;
 650   return;
 651 }
 652
 653 // ================================================================================
 654 // closest distance between a point (h1,d1) and a straigt line (h2,d2,h3) in 2 dim.
 655 // ================================================================================
 656 double FGApproach::calc_psl_dist(const double &h1, const double &d1,
 657                                  const double &h2, const double &d2,
 658                                  const double &h3)
 659 {
 660   double a1 = h1 * SGD_DEGREES_TO_RADIANS;
 661   double a2 = h2 * SGD_DEGREES_TO_RADIANS;
 662   double a3 = h3 * SGD_DEGREES_TO_RADIANS;
 663   double x1 = cos(a1) * d1;
 664   double y1 = sin(a1) * d1;
 665   double x2 = cos(a2) * d2;
 666   double y2 = sin(a2) * d2;
 667   double x3 = cos(a3);
 668   double y3 = sin(a3);
 669
 670   // formula: dis = sqrt( (v1-v2)**2 - ((v1-v2)*v3)**2 ); vi = (xi,yi)
 671   double val1   = (x1-x2)*(x1-x2) + (y1-y2)*(y1-y2);
 672   double val2   = ((x1-x2)*x3 + (y1-y2)*y3) * ((x1-x2)*x3 + (y1-y2)*y3);
 673   double dis    = val1 - val2;
 674   // now get sign for offset
 675   //cout << x1 << " " << x2 << " " << y1 << " " << y2 << " "
 676   //     << x3 << " " << y3 << " "
 677   //     << val1 << " " << val2 << " " << dis << endl;
 678   x3 *= sqrt(val2);
 679   y3 *= sqrt(val2);
 680   double da = fabs(atan2(y3,x3) - atan2(y1-y2,x1-x2));
 681   if ( da > SGD_PI ) da -= 2*SGD_PI;
 682   if ( fabs(da) > SGD_PI/2.) {
 683     //if ( x3*(x1-x2) < 0.0 && y3*(y1-y2) < 0.0) {
 684     x3 *= -1.0;
 685     y3 *= -1.0;
 686   }
 687   //cout << x3 << " " << y3 << endl;
 688   double dis1   = x1-x2-x3;
 689   double dis2   = y1-y2-y3;
 690   dis = sqrt(dis);
 691   da = atan2(dis2,dis1);
 692   if ( da < 0.0 ) da  += 2*SGD_PI;
 693   if ( da < a3 )  dis *= -1.0;
 694   //cout << dis1 << " " << dis2 << " " << da*SGD_RADIANS_TO_DEGREES << " " << h3
 695   //     << " " << sqrt(dis1*dis1 + dis2*dis2) << " " << dis << endl;
 696   //cout << atan2(dis2,dis1)*SGD_RADIANS_TO_DEGREES << " " << dis << endl;
 697
 698   return dis;
 699 }
 700
 701
 702 // ========================================================================
 703 // Calculate new bear/dist given starting bear/dis, and offset radial,
 704 // and distance.
 705 // ========================================================================
 706 void FGApproach::calc_cd_head_dist(const double &h1, const double &d1,
 707                                    const double &course, const double &dist,
 708                                    double *h2, double *d2)
 709 {
 710   double a1 = h1 * SGD_DEGREES_TO_RADIANS;
 711   double a2 = course * SGD_DEGREES_TO_RADIANS;
 712   double x1 = cos(a1) * d1;
 713   double y1 = sin(a1) * d1;
 714   double x2 = cos(a2) * dist;
 715   double y2 = sin(a2) * dist;
 716
 717   *d2 = sqrt((x1+x2)*(x1+x2) + (y1+y2)*(y1+y2));
 718   *h2 = atan2( (y1+y2), (x1+x2) ) * SGD_RADIANS_TO_DEGREES;
 719   if ( *h2 < 0 ) *h2 = *h2+360;
 720 }
 721
 722
 723
 724 // ========================================================================
 725 // get heading and distance between two points; point1 ---> point2
 726 // ========================================================================
 727 void FGApproach::calc_hd_course_dist(const double &h1, const double &d1,
 728                                      const double &h2, const double &d2,
 729                                      double *course, double *dist)
 730 {
 731   double a1 = h1 * SGD_DEGREES_TO_RADIANS;
 732   double a2 = h2 * SGD_DEGREES_TO_RADIANS;
 733   double x1 = cos(a1) * d1;
 734   double y1 = sin(a1) * d1;
 735   double x2 = cos(a2) * d2;
 736   double y2 = sin(a2) * d2;
 737
 738   *dist   = sqrt( (y2-y1)*(y2-y1) + (x2-x1)*(x2-x1) );
 739   *course = atan2( (y2-y1), (x2-x1) ) * SGD_RADIANS_TO_DEGREES;
 740   if ( *course < 0 ) *course = *course+360;
 741   //cout << x1 << " " << y1 << " " << x2 << " " << y2 << " " << *dist << " " << *course << endl;
 742 }
 743
 744
 745
 746 int FGApproach::RemovePlane() {
 747
 748   // first check if anything has to be done
 749   bool rmplane = false;
 750   int i;
 751
 752   for (i=0; i<num_planes; i++) {
 753     if (planes[i].dist > range*SG_NM_TO_METER) {
 754       rmplane = true;
 755       break;
 756     }
 757   }
 758   if (!rmplane) return num_planes;
 759
 760   // now make a copy of the plane list
 761   PlaneApp tmp[max_planes];
 762   for (i=0; i<num_planes; i++) {
 763     tmp[i] = planes[i];
 764   }
 765
 766   int np = 0;
 767   // now check which planes are still in range
 768   for (i=0; i<num_planes; i++) {
 769     if (tmp[i].dist <= range*SG_NM_TO_METER) {
 770       planes[np] = tmp[i];
 771       np += 1;
 772     }
 773   }
 774   num_planes = np;
 775
 776   return num_planes;
 777 }