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/math/polar3d.hxx>
  29 #include <simgear/misc/sg_path.hxx>
  30
  31 #ifdef FG_WEATHERCM
  32 # include <WeatherCM/FGLocalWeatherDatabase.h>
  33 #else
  34 # include <Environment/environment_mgr.hxx>
  35 # include <Environment/environment.hxx>
  36 #endif
  37
  38
  39 #include <GUI/gui.h>
  40
  41 //Constructor
  42 FGApproach::FGApproach(){
  43   comm1_node = fgGetNode("/radios/comm[0]/frequencies/selected-mhz", true);
  44   comm2_node = fgGetNode("/radios/comm[1]/frequencies/selected-mhz", true);
  45
  46   _type = APPROACH;
  47
  48   num_planes = 0;
  49   lon_node   = fgGetNode("/position/longitude-deg", true);
  50   lat_node   = fgGetNode("/position/latitude-deg", true);
  51   elev_node  = fgGetNode("/position/altitude-ft", true);
  52   hdg_node   = fgGetNode("/orientation/heading-deg", true);
  53   speed_node = fgGetNode("/velocities/airspeed-kt", true);
  54   etime_node = fgGetNode("/sim/time/elapsed-ms", true);
  55
  56   first = true;
  57   active_runway = "";
  58   int i;
  59   for ( i=0; i<max_planes; i++) {
  60     planes[i].contact   = 0;
  61     planes[i].wpn       = 0;
  62     planes[i].dnwp      = -999.;
  63     planes[i].on_crs    = true;
  64     planes[i].turn_rate = 10.0;
  65     planes[i].desc_rate = 1000.0;
  66     planes[i].clmb_rate = 500.0;
  67     planes[i].tlm       = 0.0;
  68     planes[i].lmc.c1    = 0;
  69     planes[i].lmc.c2    = 0;
  70     planes[i].lmc.c3    = -1;
  71     planes[i].wp_change = false;
  72   }
  73 }
  74
  75 //Destructor
  76 FGApproach::~FGApproach(){
  77 }
  78
  79 void FGApproach::Init() {
  80   display = false;
  81 }
  82
  83
  84
  85 // ============================================================================
  86 // the main update function
  87 // ============================================================================
  88 void FGApproach::Update(double dt) {
  89
  90         const int max_trans = 20;
  91         FGTransmission tmissions[max_trans];
  92         int    wpn;
  93         atc_type station = APPROACH;
  94         TransCode code;
  95         TransPar TPar;
  96         int    i,j;
  97         //double course, d,
  98         double adif, datp;
  99         //char   buf[10];
 100         string message;
 101         //static string atcmsg1[10];
 102         //static string atcmsg2[10];
 103         string mentry;
 104         string transm;
 105         TransPar tpars;
 106         //static bool TransDisplayed = false;
 107
 108         update_plane_dat();
 109         if ( active_runway == "" ) get_active_runway();
 110
 111         double comm1_freq = comm1_node->getDoubleValue();
 112
 113         //bool DisplayTransmissions = true;
 114
 115         for (i=0; i<num_planes; i++) {
 116                 if ( planes[i].ident == "Player") {
 117                         station = APPROACH;
 118                         tpars.station = name;
 119                         tpars.callsign = "Player";
 120                         tpars.airport = ident;
 121
 122                         //cout << "ident = " << ident << " name = " << name << '\n';
 123
 124                         int num_trans = 0;
 125                         // is the frequency of the station tuned in?
 126                         if ( freq == (int)(comm1_freq*100.0 + 0.5) ) {
 127                                 current_transmissionlist->query_station( station, tmissions, max_trans, num_trans );
 128                                 // loop over all transmissions for station
 129                                 for ( j=0; j<=num_trans-1; j++ ) {
 130                                         code = tmissions[j].get_code();
 131                                         //cout << "code is " << code.c1 << "  " << code.c2 << "  " << code.c3 << '\n';
 132                                         // select proper transmissions
 133                                         if(code.c3 != 2) {    // DCL - hack to prevent request crossing airspace being displayed since this isn't implemented yet.
 134                                             if ( ( code.c2 == -1 && planes[i].lmc.c3 == 0 ) ||
 135                                                     ( code.c1 == 0  && code.c2 == planes[i].lmc.c2 ) ) {
 136                                                     mentry = current_transmissionlist->gen_text(station, code, tpars, false);
 137                                                     transm = current_transmissionlist->gen_text(station, code, tpars, true);
 138                                                     // is the transmission already registered?
 139                                                     if (!current_atcdialog->trans_reg( ident, transm, APPROACH )) {
 140                                                             current_atcdialog->add_entry( ident, transm, mentry, APPROACH, 0 );
 141                                                     }
 142                                             }
 143                                         }
 144                                 }
 145                         }
 146                 }
 147         }
 148
 149         for ( i=0; i<num_planes; i++ ) {
 150                 //cout << "TPar.airport = " << TPar.airport << " TPar.station = " << TPar.station << " TPar.callsign = " << TPar.callsign << '\n';
 151                 //if ( planes[i].ident == TPar.callsign && name == TPar.airport && TPar.station == "approach" ) {
 152                         //if ( TPar.request && TPar.intention == "landing" && ident == TPar.intid) {
 153                         if(planes[i].ident == "Player" && fgGetBool("/sim/atc/opt0")) {
 154                                 //cout << "Landing requested\n";
 155                                 fgSetBool("/sim/atc/opt0", false);
 156                                 planes[i].wpn = 0;
 157                                 // ===========================
 158                                 // === calculate waypoints ===
 159                                 // ===========================
 160                                 calc_wp( i );
 161                                 update_param( i );
 162                                 wpn = planes[i].wpn-1;
 163                                 planes[i].aalt = planes[i].wpts[wpn-1][2];
 164                                 planes[i].ahdg = planes[i].wpts[wpn][4];
 165
 166                                 // generate the message
 167                                 code.c1 = 1;
 168                                 code.c2 = 1;
 169                                 code.c3 = 0;
 170                                 adif = angle_diff_deg( planes[i].hdg, planes[i].ahdg );
 171                                 tpars.station = name;
 172                                 tpars.callsign = "Player";
 173                                 if ( adif < 0 ) tpars.tdir = 1;
 174                                 else            tpars.tdir = 2;
 175                                 tpars.heading = planes[i].ahdg;
 176                                 if      (planes[i].alt-planes[i].aalt > 100.0)  tpars.VDir = 1;
 177                                 else if (planes[i].alt-planes[i].aalt < -100.0) tpars.VDir = 3;
 178                                 else tpars.VDir = 2;
 179                                 tpars.alt = planes[i].aalt;
 180                                 message = current_transmissionlist->gen_text(station, code, tpars, true );
 181                                 //cout << message << '\n';
 182                                 globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 183                                 planes[i].lmc = code;
 184                                 planes[i].tlm = etime_node->getDoubleValue();
 185                                 planes[i].on_crs = true;
 186                                 planes[i].contact = 1;
 187                         }
 188                 //}
 189
 190                 //if(1) {
 191                 if ( planes[i].contact == 1 ) {
 192                         // =========================
 193                         // === update parameters ===
 194                         // =========================
 195                         update_param( i );
 196                         //cout << planes[i].brg << " " << planes[i].dist << " " << planes[i].wpts[wpn+1][0]
 197                         //<< " " << planes[i].wpts[wpn+1][1] << " " << planes[i].wpts[wpn+1][4]
 198                         //cout << wpn << " distance to current course = " << planes[i].dcc << endl;
 199                         //cout << etime_node->getDoubleValue() << endl;
 200
 201                         // =========================
 202                         // === reached waypoint? ===
 203                         // =========================
 204                         wpn = planes[i].wpn-2;
 205                         adif = angle_diff_deg( planes[i].hdg, planes[i].wpts[wpn][4] )
 206                         * SGD_DEGREES_TO_RADIANS;
 207                         datp = 2*sin(fabs(adif)/2.0)*sin(fabs(adif)/2.0) *
 208                                planes[i].spd/3600. * planes[i].turn_rate +
 209                                planes[i].spd/3600. * 3.0;
 210                         //cout << adif/SGD_DEGREES_TO_RADIANS << " "
 211                         //     << datp << " " << planes[i].dnc << " " << planes[i].dcc <<endl;
 212                         if ( fabs(planes[i].dnc) < datp ) {
 213                         //if ( fabs(planes[i].dnc) < 0.3 && planes[i].dnwp < 1.0 ) {
 214                                 //cout << "Reached next waypoint!\n";
 215                                 planes[i].wpn -= 1;
 216                                 wpn = planes[i].wpn-1;
 217                                 planes[i].ahdg = planes[i].wpts[wpn][4];
 218                                 planes[i].aalt = planes[i].wpts[wpn-1][2];
 219                                 planes[i].wp_change = true;
 220
 221                                 // generate the message
 222                                 adif = angle_diff_deg( planes[i].hdg, planes[i].ahdg );
 223                                 tpars.station = name;
 224                                 tpars.callsign = "Player";
 225                                 if ( adif < 0 ) tpars.tdir = 1;
 226                                 else            tpars.tdir = 2;
 227                                 tpars.heading = planes[i].ahdg;
 228
 229                                 if ( wpn-1 != 0) {
 230                                         code.c1 = 1;
 231                                         code.c2 = 1;
 232                                         code.c3 = 0;
 233                                         if      (planes[i].alt-planes[i].aalt > 100.0)  tpars.VDir = 1;
 234                                         else if (planes[i].alt-planes[i].aalt < -100.0) tpars.VDir = 3;
 235                                         else tpars.VDir = 2;
 236                                         tpars.alt = planes[i].aalt;
 237                                         message = current_transmissionlist->gen_text(station, code, tpars, true );
 238                                         //cout << "Approach transmitting...\n";
 239                                         //cout << message << endl;
 240                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 241
 242                                 }
 243                                 else {
 244                                         code.c1 = 1;
 245                                         code.c2 = 3;
 246                                         code.c3 = 0;
 247                                         tpars.runway = active_runway;
 248                                         message = current_transmissionlist->gen_text(station, code, tpars, true);
 249                                         //cout << "Approach transmitting 2 ...\n";
 250                                         //cout << message << endl;
 251                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 252                                 }
 253                                 planes[i].lmc = code;
 254                                 planes[i].tlm = etime_node->getDoubleValue();
 255                                 planes[i].on_crs = true;
 256
 257                                 update_param( i );
 258                         }
 259
 260                         // =========================
 261                         // === come off course ? ===
 262                         // =========================
 263                         if ( fabs(planes[i].dcc) > 1.0 &&
 264                            ( !planes[i].wp_change || etime_node->getDoubleValue() - planes[i].tlm > tbm ) ) {
 265                                 //cout << "Off course!\n";
 266                                 if ( planes[i].on_crs ) {
 267                                         if ( planes[i].dcc < 0) {
 268                                                 planes[i].ahdg += 30.0;
 269                                         }
 270                                         else {
 271                                                 planes[i].ahdg -= 30.0;
 272                                         }
 273                                         if (planes[i].ahdg > 360.0) planes[i].ahdg -= 360.0;
 274                                         else if (planes[i].ahdg < 0.0) planes[i].ahdg += 360.0;
 275                                 }
 276                                 //cout << planes[i].on_crs << " "
 277                                 //     << angle_diff_deg( planes[i].hdg, planes[i].ahdg) << " "
 278                                 //     << etime_node->getDoubleValue() << " "
 279                                 //     << planes[i].tlm << endl;
 280                                 // generate the message
 281                                 if ( planes[i].on_crs ||
 282                                    ( fabs(angle_diff_deg( planes[i].hdg, planes[i].ahdg )) >  30.0  &&
 283                                     etime_node->getDoubleValue() - planes[i].tlm > tbm) ) {
 284                                         // generate the message
 285                                         code.c1 = 1;
 286                                         code.c2 = 4;
 287                                         code.c3 = 0;
 288                                         adif = angle_diff_deg( planes[i].hdg, planes[i].ahdg );
 289                                         tpars.station = name;
 290                                         tpars.callsign = "Player";
 291                                         tpars.miles   = fabs(planes[i].dcc);
 292                                         if ( adif < 0 ) tpars.tdir = 1;
 293                                         else            tpars.tdir = 2;
 294                                         tpars.heading = planes[i].ahdg;
 295                                         message = current_transmissionlist->gen_text(station, code, tpars, true);
 296                                         //cout << "Approach transmitting 3 ...\n";
 297                                         //cout << message << '\n';
 298                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 299                                         planes[i].lmc = code;
 300                                         planes[i].tlm = etime_node->getDoubleValue();
 301                                 }
 302
 303                                 planes[i].on_crs = false;
 304                         }
 305                         else if ( !planes[i].on_crs ) {
 306                                 //cout << "Off course 2!\n";
 307                                 wpn = planes[i].wpn-1;
 308                                 adif = angle_diff_deg( planes[i].hdg, planes[i].wpts[wpn][4] )
 309                                        * SGD_DEGREES_TO_RADIANS;
 310                                 datp = 2*sin(fabs(adif)/2.0)*sin(fabs(adif)/2.0) *
 311                                 planes[i].spd/3600. * planes[i].turn_rate +
 312                                 planes[i].spd/3600. * 3.0;
 313                                 if ( fabs(planes[i].dcc) < datp ) {
 314                                         planes[i].ahdg = fabs(planes[i].wpts[wpn][4]);
 315
 316                                         // generate the message
 317                                         code.c1 = 1;
 318                                         code.c2 = 2;
 319                                         code.c3 = 0;
 320                                         tpars.station = name;
 321                                         tpars.callsign = "Player";
 322                                         if ( adif < 0 ) tpars.tdir = 1;
 323                                         else            tpars.tdir = 2;
 324                                         tpars.heading = planes[i].ahdg;
 325                                         message = current_transmissionlist->gen_text(station, code, tpars, true);
 326                                         //cout << "Approach transmitting 4 ...\n";
 327                                         //cout << message << '\n';
 328                                         globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 329                                         planes[i].lmc = code;
 330                                         planes[i].tlm = etime_node->getDoubleValue();
 331
 332                                         planes[i].on_crs = true;
 333                                 }
 334                         }
 335                         else if ( planes[i].wp_change  ) {
 336                                 planes[i].wp_change = false;
 337                         }
 338
 339                         // ===================================================================
 340                         // === Less than two minutes away from touchdown? -> Contact Tower ===
 341                         // ===================================================================
 342                         if ( planes[i].wpn == 2 && planes[i].dnwp < planes[i].spd/60.*2.0 ) {
 343
 344                                 double freq = 121.95;   // Hardwired - FIXME
 345                                 // generate message
 346                                 code.c1 = 1;
 347                                 code.c2 = 5;
 348                                 code.c3 = 0;
 349                                 tpars.station = name;
 350                                 tpars.callsign = "Player";
 351                                 tpars.freq    = freq;
 352                                 message = current_transmissionlist->gen_text(station, code, tpars, true);
 353                                 //cout << "Approach transmitting 5 ...\n";
 354                                 //cout << message << '\n';
 355                                 globals->get_ATC_display()->RegisterSingleMessage( message, 0 );
 356                                 planes[i].lmc = code;
 357                                 planes[i].tlm = etime_node->getDoubleValue();
 358
 359                                 planes[i].contact = 2;
 360                         }
 361                 }
 362         }
 363 }
 364
 365
 366 // ============================================================================
 367 // update course parameters
 368 // ============================================================================
 369 void FGApproach::update_param( const int &i ) {
 370
 371   double course, d;
 372
 373   int wpn = planes[i].wpn-1;            // this is the current waypoint
 374
 375   planes[i].dcc  = calc_psl_dist(planes[i].brg, planes[i].dist,
 376                                  planes[i].wpts[wpn][0], planes[i].wpts[wpn][1],
 377                                  planes[i].wpts[wpn][4]);
 378   planes[i].dnc  = calc_psl_dist(planes[i].brg, planes[i].dist,
 379                                  planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 380                                  planes[i].wpts[wpn-1][4]);
 381   calc_hd_course_dist(planes[i].brg, planes[i].dist,
 382                       planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 383                       &course, &d);
 384   planes[i].dnwp = d;
 385
 386 }
 387
 388 // ============================================================================
 389 // smallest difference between two angles in degree
 390 // difference is negative if a1 > a2 and positive if a2 > a1
 391 // ===========================================================================
 392 double FGApproach::angle_diff_deg( const double &a1, const double &a2) {
 393
 394   double a3 = a2 - a1;
 395   if (a3 < 180.0) a3 += 360.0;
 396   if (a3 > 180.0) a3 -= 360.0;
 397
 398   return a3;
 399 }
 400
 401 // ============================================================================
 402 // calculate waypoints
 403 // ============================================================================
 404 void FGApproach::calc_wp( const int &i ) {
 405
 406         int j;
 407         double course, d, cd, a1;
 408
 409         int wpn = planes[i].wpn;
 410         // waypoint 0: Threshold of active runway
 411         calc_gc_course_dist(Point3D(lon*SGD_DEGREES_TO_RADIANS, lat*SGD_DEGREES_TO_RADIANS, 0.0),
 412                             Point3D(active_rw_lon*SGD_DEGREES_TO_RADIANS,active_rw_lat*SGD_DEGREES_TO_RADIANS, 0.0 ),
 413                             &course, &d);
 414         double d1 = active_rw_hdg+180.0;
 415         if ( d1 > 360.0 ) d1 -=360.0;
 416         calc_cd_head_dist(360.0-course*SGD_RADIANS_TO_DEGREES, d/SG_NM_TO_METER,
 417                           d1, active_rw_len/SG_NM_TO_METER/2.0,
 418                           &planes[i].wpts[wpn][0], &planes[i].wpts[wpn][1]);
 419         planes[i].wpts[wpn][2] = elev;
 420         planes[i].wpts[wpn][4] = 0.0;
 421         planes[i].wpts[wpn][5] = 0.0;
 422         wpn += 1;
 423
 424         // ======================
 425         // horizontal navigation
 426         // ======================
 427         // waypoint 1: point for turning onto final
 428         calc_cd_head_dist(planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1], d1, lfl,
 429                           &planes[i].wpts[wpn][0], &planes[i].wpts[wpn][1]);
 430         calc_hd_course_dist(planes[i].wpts[wpn][0],   planes[i].wpts[wpn][1],
 431                             planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 432                             &course, &d);
 433         planes[i].wpts[wpn][4] = course;
 434         planes[i].wpts[wpn][5] = d;
 435         wpn += 1;
 436
 437         // calculate course and distance from plane position to waypoint 1
 438         calc_hd_course_dist(planes[i].brg, planes[i].dist, planes[i].wpts[1][0],
 439                             planes[i].wpts[1][1], &course, &d);
 440         // check if airport is not between plane and waypoint 1 and
 441         // DCA to airport on course to waypoint 1 is larger than 10 miles
 442         double zero = 0.0;
 443         if ( fabs(angle_diff_deg( planes[i].wpts[1][0], planes[i].brg  )) < 90.0 ||
 444                 calc_psl_dist( zero, zero, planes[i].brg, planes[i].dist, course ) > 10.0 ) {
 445                 // check if turning angle at waypoint 1 would be > max_ta
 446                 if ( fabs(angle_diff_deg( planes[i].wpts[1][4], course )) > max_ta ) {
 447                         cd = calc_psl_dist(planes[i].brg, planes[i].dist,
 448                              planes[i].wpts[1][0], planes[i].wpts[1][1],
 449                              planes[i].wpts[1][4]);
 450                         a1 = atan2(cd,planes[i].wpts[1][1]);
 451                         planes[i].wpts[wpn][0] = planes[i].wpts[1][0] - a1/SGD_DEGREES_TO_RADIANS;
 452                         if ( planes[i].wpts[wpn][0] < 0.0)   planes[i].wpts[wpn][0] += 360.0;
 453                         if ( planes[i].wpts[wpn][0] > 360.0) planes[i].wpts[wpn][0] -= 360.0;
 454                         planes[i].wpts[wpn][1] = fabs(cd) / sin(fabs(a1));
 455                         calc_hd_course_dist(planes[i].wpts[wpn][0],   planes[i].wpts[wpn][1],
 456                                             planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 457                                             &course, &d);
 458                         planes[i].wpts[wpn][4] = course;
 459                         planes[i].wpts[wpn][5] = d;
 460                         wpn += 1;
 461
 462                         calc_hd_course_dist(planes[i].brg, planes[i].dist, planes[i].wpts[wpn-1][0],
 463                                             planes[i].wpts[wpn-1][1], &course, &d);
 464                 }
 465         } else {
 466                 double leg = 10.0;
 467                 a1 = atan2(planes[i].wpts[1][1], leg );
 468
 469                 if ( angle_diff_deg(planes[i].brg,planes[i].wpts[1][0]) < 0 )
 470                         planes[i].wpts[wpn][0] = planes[i].wpts[1][0] + a1/SGD_DEGREES_TO_RADIANS;
 471                 else planes[i].wpts[wpn][0] = planes[i].wpts[1][0] - a1/SGD_DEGREES_TO_RADIANS;
 472
 473                 planes[i].wpts[wpn][1] = sqrt( planes[i].wpts[1][1]*planes[i].wpts[1][1] + leg*leg );
 474                 calc_hd_course_dist(planes[i].wpts[wpn][0],   planes[i].wpts[wpn][1],
 475                                     planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 476                                     &course, &d);
 477                 planes[i].wpts[wpn][4] = course;
 478                 planes[i].wpts[wpn][5] = d;
 479                 wpn += 1;
 480
 481                 calc_hd_course_dist(planes[i].brg, planes[i].dist,
 482                                     planes[i].wpts[wpn-1][0], planes[i].wpts[wpn-1][1],
 483                                     &course, &d);
 484         }
 485
 486         planes[i].wpts[wpn][0] = planes[i].brg;
 487         planes[i].wpts[wpn][1] = planes[i].dist;
 488         planes[i].wpts[wpn][2] = planes[i].alt;
 489         planes[i].wpts[wpn][4] = course;
 490         planes[i].wpts[wpn][5] = d;
 491         wpn += 1;
 492
 493         planes[i].wpn = wpn;
 494
 495         // Now check if legs are too short or if legs can be shortend
 496         // legs must be at least 2 flight minutes long
 497         double mdist = planes[i].spd / 60.0 * 2.0;
 498         for ( j=2; j<wpn-1; ++j ) {
 499                 if ( planes[i].wpts[j][1] < mdist) {
 500                 }
 501         }
 502
 503         // ====================
 504         // vertical navigation
 505         // ====================
 506         double alt = elev+3000.0;
 507         planes[i].wpts[1][2] = round_alt( true, alt );
 508         for ( j=2; j<wpn-1; ++j ) {
 509                 double dalt = planes[i].alt - planes[i].wpts[j-1][2];
 510                 if ( dalt > 0 ) {
 511                         alt = planes[i].wpts[j-1][2] +
 512                               (planes[i].wpts[j][5] / planes[i].spd) * 60.0 * planes[i].desc_rate;
 513                         planes[i].wpts[j][2] = round_alt( false, alt );
 514                         if ( planes[i].wpts[j][2] > planes[i].alt )
 515                                 planes[i].wpts[j][2] = round_alt( false, planes[i].alt );
 516                 }
 517                 else {
 518                         planes[i].wpts[j][2] = planes[i].wpts[1][2];
 519                 }
 520         }
 521
 522         cout << "Plane position: " << planes[i].brg << " " << planes[i].dist << endl;
 523         for ( j=0; j<wpn; ++j ) {
 524                 cout << "Waypoint " << j << endl;
 525                 cout << "------------------" << endl;
 526                 cout << planes[i].wpts[j][0] << "   " << planes[i].wpts[j][1]
 527                      << "   " << planes[i].wpts[j][2] << "   " << planes[i].wpts[j][5];
 528                 cout << endl << endl;
 529         }
 530
 531 }
 532
 533
 534 // ============================================================================
 535 // round altitude value to next highest/lowest 500 feet
 536 // ============================================================================
 537 double FGApproach::round_alt( const bool hl, double alt ) {
 538
 539   alt = alt/1000.0;
 540   if ( hl ) {
 541     if ( alt > (int)(alt)+0.5 ) alt = ((int)(alt)+1)*1000.0;
 542     else alt = ((int)(alt)+0.5)*1000.0;
 543   }
 544   else {
 545     if ( alt > (int)(alt)+0.5 ) alt = ((int)(alt)+0.5)*1000.0;
 546     else alt = ((int)(alt))*1000.0;
 547   }
 548
 549   return alt;
 550 }
 551
 552
 553 // ============================================================================
 554 // get active runway
 555 // ============================================================================
 556 void FGApproach::get_active_runway() {
 557         //cout << "Entering FGApproach::get_active_runway()\n";
 558
 559 #ifdef FG_WEATHERCM
 560   sgVec3 position = { lat, lon, elev };
 561   FGPhysicalProperty stationweather = WeatherDatabase->get(position);
 562 #else
 563   FGEnvironment stationweather =
 564       ((FGEnvironmentMgr *)globals->get_subsystem("environment"))
 565         ->getEnvironment(lat, lon, elev);
 566 #endif
 567
 568 #ifdef FG_WEATHERCM
 569   //Set the heading to into the wind
 570   double wind_x = stationweather.Wind[0];
 571   double wind_y = stationweather.Wind[1];
 572
 573   double speed = sqrt( wind_x*wind_x + wind_y*wind_y ) * SG_METER_TO_NM / (60.0*60.0);
 574   double hdg;
 575
 576   //If no wind use 270degrees
 577   if(speed == 0) {
 578     hdg = 270;
 579   } else {
 580     // //normalize the wind to get the direction
 581     //wind_x /= speed; wind_y /= speed;
 582
 583     hdg = - atan2 ( wind_x, wind_y ) * SG_RADIANS_TO_DEGREES ;
 584     if (hdg < 0.0)
 585       hdg += 360.0;
 586   }
 587 #else
 588   double hdg = stationweather.get_wind_from_heading_deg();
 589 #endif
 590
 591   FGRunway runway;
 592   if ( globals->get_runways()->search( ident, int(hdg), &runway) ) {
 593     active_runway = runway.rwy_no;
 594     active_rw_hdg = runway.heading;
 595     active_rw_lon = runway.lon;
 596     active_rw_lat = runway.lat;
 597     active_rw_len = runway.length;
 598     //cout << "Active runway is: " << active_runway << "  heading = "
 599     // << active_rw_hdg
 600     // << " lon = " << active_rw_lon
 601     // << " lat = " << active_rw_lat <<endl;
 602   }
 603   else cout << "FGRunways search failed\n";
 604
 605 }
 606
 607 // ========================================================================
 608 // update infos about plane
 609 // ========================================================================
 610 void FGApproach::update_plane_dat() {
 611
 612   //cout << "Update Approach " << ident << "   " << num_planes << " registered" << endl;
 613   // update plane positions
 614   int i;
 615   for (i=0; i<num_planes; i++) {
 616     planes[i].lon = lon_node->getDoubleValue();
 617     planes[i].lat = lat_node->getDoubleValue();
 618     planes[i].alt = elev_node->getDoubleValue();
 619     planes[i].hdg = hdg_node->getDoubleValue();
 620     planes[i].spd = speed_node->getDoubleValue();
 621
 622     /*Point3D aircraft = sgGeodToCart( Point3D(planes[i].lon*SGD_DEGREES_TO_RADIANS,
 623                                              planes[i].lat*SGD_DEGREES_TO_RADIANS,
 624                                              planes[i].alt*SG_FEET_TO_METER) );*/
 625     double course, distance;
 626     calc_gc_course_dist(Point3D(lon*SGD_DEGREES_TO_RADIANS, lat*SGD_DEGREES_TO_RADIANS, 0.0),
 627                         Point3D(planes[i].lon*SGD_DEGREES_TO_RADIANS,planes[i].lat*SGD_DEGREES_TO_RADIANS, 0.0 ),
 628                         &course, &distance);
 629     planes[i].dist = distance/SG_NM_TO_METER;
 630     planes[i].brg  = 360.0-course*SGD_RADIANS_TO_DEGREES;
 631
 632     //cout << "Plane Id: " << planes[i].ident << "  Distance to " << ident
 633     // << " is " << planes[i].dist << " miles   " << "Bearing " << planes[i].brg << endl;
 634
 635   }
 636 }
 637
 638 // =======================================================================
 639 // Add plane to Approach list
 640 // =======================================================================
 641 void FGApproach::AddPlane(string pid) {
 642
 643   int i;
 644   for ( i=0; i<num_planes; i++) {
 645     if ( planes[i].ident == pid) {
 646       //cout << "Plane already registered: " << planes[i].ident << ' ' << ident << ' ' << num_planes << endl;
 647       return;
 648     }
 649   }
 650   planes[num_planes].ident = pid;
 651   ++num_planes;
 652   //cout << "Plane added to list: " << ident << " " << num_planes << endl;
 653   return;
 654 }
 655
 656 // ================================================================================
 657 // closest distance between a point (h1,d1) and a straigt line (h2,d2,h3) in 2 dim.
 658 // ================================================================================
 659 double FGApproach::calc_psl_dist(const double &h1, const double &d1,
 660                                  const double &h2, const double &d2,
 661                                  const double &h3)
 662 {
 663   double a1 = h1 * SGD_DEGREES_TO_RADIANS;
 664   double a2 = h2 * SGD_DEGREES_TO_RADIANS;
 665   double a3 = h3 * SGD_DEGREES_TO_RADIANS;
 666   double x1 = cos(a1) * d1;
 667   double y1 = sin(a1) * d1;
 668   double x2 = cos(a2) * d2;
 669   double y2 = sin(a2) * d2;
 670   double x3 = cos(a3);
 671   double y3 = sin(a3);
 672
 673   // formula: dis = sqrt( (v1-v2)**2 - ((v1-v2)*v3)**2 ); vi = (xi,yi)
 674   double val1   = (x1-x2)*(x1-x2) + (y1-y2)*(y1-y2);
 675   double val2   = ((x1-x2)*x3 + (y1-y2)*y3) * ((x1-x2)*x3 + (y1-y2)*y3);
 676   double dis    = val1 - val2;
 677   // now get sign for offset
 678   //cout << x1 << " " << x2 << " " << y1 << " " << y2 << " "
 679   //     << x3 << " " << y3 << " "
 680   //     << val1 << " " << val2 << " " << dis << endl;
 681   x3 *= sqrt(val2);
 682   y3 *= sqrt(val2);
 683   double da = fabs(atan2(y3,x3) - atan2(y1-y2,x1-x2));
 684   if ( da > SGD_PI ) da -= 2*SGD_PI;
 685   if ( fabs(da) > SGD_PI/2.) {
 686     //if ( x3*(x1-x2) < 0.0 && y3*(y1-y2) < 0.0) {
 687     x3 *= -1.0;
 688     y3 *= -1.0;
 689   }
 690   //cout << x3 << " " << y3 << endl;
 691   double dis1   = x1-x2-x3;
 692   double dis2   = y1-y2-y3;
 693   dis = sqrt(dis);
 694   da = atan2(dis2,dis1);
 695   if ( da < 0.0 ) da  += 2*SGD_PI;
 696   if ( da < a3 )  dis *= -1.0;
 697   //cout << dis1 << " " << dis2 << " " << da*SGD_RADIANS_TO_DEGREES << " " << h3
 698   //     << " " << sqrt(dis1*dis1 + dis2*dis2) << " " << dis << endl;
 699   //cout << atan2(dis2,dis1)*SGD_RADIANS_TO_DEGREES << " " << dis << endl;
 700
 701   return dis;
 702 }
 703
 704
 705 // ========================================================================
 706 // Calculate new bear/dist given starting bear/dis, and offset radial,
 707 // and distance.
 708 // ========================================================================
 709 void FGApproach::calc_cd_head_dist(const double &h1, const double &d1,
 710                                    const double &course, const double &dist,
 711                                    double *h2, double *d2)
 712 {
 713   double a1 = h1 * SGD_DEGREES_TO_RADIANS;
 714   double a2 = course * SGD_DEGREES_TO_RADIANS;
 715   double x1 = cos(a1) * d1;
 716   double y1 = sin(a1) * d1;
 717   double x2 = cos(a2) * dist;
 718   double y2 = sin(a2) * dist;
 719
 720   *d2 = sqrt((x1+x2)*(x1+x2) + (y1+y2)*(y1+y2));
 721   *h2 = atan2( (y1+y2), (x1+x2) ) * SGD_RADIANS_TO_DEGREES;
 722   if ( *h2 < 0 ) *h2 = *h2+360;
 723 }
 724
 725
 726
 727 // ========================================================================
 728 // get heading and distance between two points; point1 ---> point2
 729 // ========================================================================
 730 void FGApproach::calc_hd_course_dist(const double &h1, const double &d1,
 731                                      const double &h2, const double &d2,
 732                                      double *course, double *dist)
 733 {
 734   double a1 = h1 * SGD_DEGREES_TO_RADIANS;
 735   double a2 = h2 * SGD_DEGREES_TO_RADIANS;
 736   double x1 = cos(a1) * d1;
 737   double y1 = sin(a1) * d1;
 738   double x2 = cos(a2) * d2;
 739   double y2 = sin(a2) * d2;
 740
 741   *dist   = sqrt( (y2-y1)*(y2-y1) + (x2-x1)*(x2-x1) );
 742   *course = atan2( (y2-y1), (x2-x1) ) * SGD_RADIANS_TO_DEGREES;
 743   if ( *course < 0 ) *course = *course+360;
 744   //cout << x1 << " " << y1 << " " << x2 << " " << y2 << " " << *dist << " " << *course << endl;
 745 }
 746
 747
 748
 749 int FGApproach::RemovePlane() {
 750
 751   // first check if anything has to be done
 752   bool rmplane = false;
 753   int i;
 754
 755   for (i=0; i<num_planes; i++) {
 756     if (planes[i].dist > range*SG_NM_TO_METER) {
 757       rmplane = true;
 758       break;
 759     }
 760   }
 761   if (!rmplane) return num_planes;
 762
 763   // now make a copy of the plane list
 764   PlaneApp tmp[max_planes];
 765   for (i=0; i<num_planes; i++) {
 766     tmp[i] = planes[i];
 767   }
 768
 769   int np = 0;
 770   // now check which planes are still in range
 771   for (i=0; i<num_planes; i++) {
 772     if (tmp[i].dist <= range*SG_NM_TO_METER) {
 773       planes[np] = tmp[i];
 774       np += 1;
 775     }
 776   }
 777   num_planes = np;
 778
 779   return num_planes;
 780 }