source/libr2c2/trainrouteplanner.cpp

   1 #include "catalogue.h"
   2 #include "layout.h"
   3 #include "route.h"
   4 #include "train.h"
   5 #include "trainroutemetric.h"
   6 #include "trainrouteplanner.h"
   7 #include "trainrouter.h"
   8 #include "vehicle.h"
   9
  10 using namespace std;
  11 using namespace Msp;
  12
  13 namespace R2C2 {
  14
  15 TrainRoutePlanner::TrainRoutePlanner(Layout &layout)
  16 {
  17         const map<unsigned, Train *> &trains = layout.get_trains();
  18         for(map<unsigned, Train *>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
  19         {
  20                 TrainRoutingInfo info(*i->second);
  21                 if(info.router && info.router->get_destination())
  22                         routed_trains.push_back(info);
  23         }
  24
  25         queue.push_back(RoutingStep());
  26         RoutingStep &start = queue.back();
  27         for(vector<TrainRoutingInfo>::iterator i=routed_trains.begin(); i!=routed_trains.end(); ++i)
  28                 start.trains.push_back(TrainRoutingState(*i));
  29         start.update_estimate();
  30 }
  31
  32 void TrainRoutePlanner::plan()
  33 {
  34         const RoutingStep *goal = 0;
  35         while(!queue.empty())
  36         {
  37                 const RoutingStep &step = get_step();
  38                 if(step.is_goal())
  39                 {
  40                         goal = &step;
  41                         break;
  42                 }
  43
  44                 add_steps(step);
  45         }
  46
  47         if(goal)
  48                 create_routes(*goal);
  49 }
  50
  51 const TrainRoutePlanner::RoutingStep &TrainRoutePlanner::get_step()
  52 {
  53         steps.splice(steps.end(), queue, queue.begin());
  54         return steps.back();
  55 }
  56
  57 void TrainRoutePlanner::add_steps(const RoutingStep &step)
  58 {
  59         list<RoutingStep> new_steps;
  60         step.create_successors(new_steps);
  61         new_steps.sort();
  62         queue.merge(new_steps);
  63 }
  64
  65 void TrainRoutePlanner::create_routes(const RoutingStep &goal)
  66 {
  67         for(vector<TrainRoutingInfo>::iterator i=routed_trains.begin(); i!=routed_trains.end(); ++i)
  68         {
  69                 Route *route = new Route(i->train->get_layout());
  70                 route->set_name("Router");
  71                 route->set_temporary(true);
  72                 i->routes.push_front(route);
  73
  74                 for(unsigned j=0; j<3; ++j)
  75                         i->track_history[j] = 0;
  76         }
  77
  78         map<Track *, SequencingInfo *> sequenced_tracks;
  79         unsigned sequence = steps.size();
  80         for(const RoutingStep *i=&goal; i; i=i->prev)
  81                 for(vector<TrainRoutingState>::const_iterator j=i->trains.begin(); j!=i->trains.end(); ++j)
  82                 {
  83                         Track **history = j->info->track_history;
  84                         if(j->track.track()==history[0])
  85                                 continue;
  86
  87                         Route *route = j->info->routes.front();
  88                         bool start_new_route = route->has_track(*j->track);
  89                         if(!start_new_route)
  90                         {
  91                                 unsigned nls = j->track->get_n_link_slots();
  92                                 for(unsigned k=0; (!start_new_route && k<nls); ++k)
  93                                 {
  94                                         Track *link = j->track->get_link(k);
  95                                         start_new_route = (link && link!=history[0] && route->has_track(*link));
  96                                 }
  97                         }
  98
  99                         if(start_new_route)
 100                         {
 101                                 route = new Route(j->info->train->get_layout());
 102                                 route->set_name("Router");
 103                                 route->set_temporary(true);
 104                                 for(unsigned k=2; k>0; --k)
 105                                         route->add_track(*history[k]);
 106                                 j->info->routes.push_front(route);
 107                         }
 108
 109                         if(history[0])
 110                                 route->add_track(*history[0]);
 111                         for(unsigned k=2; k>0; --k)
 112                                 history[k] = history[k-1];
 113                         history[0] = j->track.track();
 114
 115                         bool waitable = j->track.endpoint().paths!=j->track->get_type().get_paths();
 116                         map<Track *, SequencingInfo *>::iterator k = sequenced_tracks.find(j->track.track());
 117                         if(k!=sequenced_tracks.end())
 118                         {
 119                                 if(!k->second->preceding)
 120                                 {
 121                                         k->second->preceding = j->info;
 122                                         k->second->sequence_in = sequence;
 123                                 }
 124                                 j->info->sequence.push_front(SequencingInfo(j->track.track(), sequence));
 125                                 if(waitable)
 126                                         k->second = &j->info->sequence.front();
 127                                 --sequence;
 128                         }
 129                         else if(waitable)
 130                         {
 131                                 j->info->sequence.push_front(SequencingInfo(j->track.track(), sequence));
 132                                 sequenced_tracks[j->track.track()] = &j->info->sequence.front();
 133                                 --sequence;
 134                         }
 135                 }
 136
 137         for(vector<TrainRoutingInfo>::iterator i=routed_trains.begin(); i!=routed_trains.end(); ++i)
 138         {
 139                 for(list<Route *>::iterator j=i->routes.begin(); j!=i->routes.end(); ++j)
 140                 {
 141                         if(j==i->routes.begin())
 142                                 i->router->set_route(*j);
 143                         else
 144                                 i->router->add_route(**j);
 145                 }
 146
 147                 for(list<SequencingInfo>::iterator j=i->sequence.begin(); j!=i->sequence.end(); ++j)
 148                 {
 149                         if(j->preceding && j->preceding!=&*i)
 150                                 i->router->add_sequence_point(j->track->get_block(), *j->preceding->train, j->sequence_in, j->sequence_out);
 151                         else
 152                                 i->router->add_sequence_point(j->track->get_block(), j->sequence_out);
 153                 }
 154         }
 155 }
 156
 157
 158 TrainRoutePlanner::SequencingInfo::SequencingInfo(Track *t, unsigned o):
 159         track(t),
 160         preceding(0),
 161         sequence_in(0),
 162         sequence_out(o)
 163 { }
 164
 165
 166 TrainRoutePlanner::TrainRoutingInfo::TrainRoutingInfo(Train &t):
 167         train(&t),
 168         speed(train->get_maximum_speed()),
 169         router(train->get_ai_of_type<TrainRouter>())
 170 {
 171         // If no maximum speed is specified, use a sensible default
 172         if(!speed)
 173                 speed = 20*train->get_layout().get_catalogue().get_scale();
 174 }
 175
 176
 177 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(Track &t, unsigned p, OccupiedTrack *n):
 178         track(&t),
 179         path_length(track->get_type().get_path_length(p)),
 180         next(n),
 181         n_tracks(next ? next->n_tracks+1 : 1),
 182         refcount(1)
 183 {
 184         if(next)
 185                 ++next->refcount;
 186 }
 187
 188 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(const OccupiedTrack &other):
 189         track(other.track),
 190         path_length(other.path_length),
 191         next(other.next),
 192         n_tracks(other.n_tracks),
 193         refcount(1)
 194 {
 195         if(next)
 196                 ++next->refcount;
 197 }
 198
 199 TrainRoutePlanner::OccupiedTrack::~OccupiedTrack()
 200 {
 201         if(next && !--next->refcount)
 202                 delete next;
 203 }
 204
 205
 206 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(TrainRoutingInfo &inf):
 207         info(&inf),
 208         occupied_tracks(0),
 209         state(MOVING),
 210         delay(info->router->get_departure_delay()),
 211         waypoint(info->router->get_n_waypoints() ? 0 : -1),
 212         blocked_by(-1)
 213 {
 214         const Vehicle *veh = &info->train->get_vehicle(0);
 215         // TODO margins
 216         TrackOffsetIter track_and_offs = veh->get_placement().get_position(VehiclePlacement::FRONT_BUFFER);
 217         track = track_and_offs.track_iter();
 218         offset = track_and_offs.offset();
 219         path = track->get_active_path();
 220
 221         while(Vehicle *next = veh->get_link(1))
 222                 veh = next;
 223         track_and_offs = veh->get_placement().get_position(VehiclePlacement::BACK_BUFFER);
 224         back_offset = track_and_offs.offset();
 225
 226         TrackIter iter = track_and_offs.track_iter();
 227         while(1)
 228         {
 229                 occupied_tracks = new OccupiedTrack(*iter, iter->get_active_path(), occupied_tracks);
 230                 if(iter.track()==track.track())
 231                         break;
 232                 iter = iter.next();
 233         }
 234
 235         update_estimate();
 236 }
 237
 238 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(const TrainRoutingState &other):
 239         info(other.info),
 240         track(other.track),
 241         path(other.path),
 242         occupied_tracks(other.occupied_tracks),
 243         offset(other.offset),
 244         back_offset(other.back_offset),
 245         state(other.state),
 246         delay(other.delay),
 247         waypoint(other.waypoint),
 248         distance_traveled(other.distance_traveled),
 249         remaining_estimate(other.remaining_estimate),
 250         wait_time(other.wait_time),
 251         blocked_by(other.blocked_by)
 252 {
 253         ++occupied_tracks->refcount;
 254 }
 255
 256 TrainRoutePlanner::TrainRoutingState::~TrainRoutingState()
 257 {
 258         if(occupied_tracks && !--occupied_tracks->refcount)
 259                 delete occupied_tracks;
 260 }
 261
 262 Time::TimeDelta TrainRoutePlanner::TrainRoutingState::get_time_to_next_track() const
 263 {
 264         return ((track->get_type().get_path_length(path)-offset)/info->speed)*Time::sec+delay;
 265 }
 266
 267 bool TrainRoutePlanner::TrainRoutingState::is_occupying(Track &trk) const
 268 {
 269         OccupiedTrack *occ = occupied_tracks;
 270         for(unsigned n=occ->n_tracks; n>0; --n, occ=occ->next)
 271                 if(occ->track==&trk)
 272                         return true;
 273         return false;
 274 }
 275
 276 bool TrainRoutePlanner::TrainRoutingState::check_arrival()
 277 {
 278         TrainRouter &router = *info->router;
 279         TrackIter next_track = track.next(path);
 280
 281         if(waypoint<0 && router.is_destination(*track) && !router.is_destination(*next_track))
 282         {
 283                 state = ARRIVED;
 284                 return true;
 285         }
 286         else if(waypoint>=0 && router.is_waypoint(waypoint, *track) && !router.is_waypoint(waypoint, *next_track))
 287         {
 288                 ++waypoint;
 289                 if(waypoint>=static_cast<int>(router.get_n_waypoints()))
 290                         waypoint = -1;
 291         }
 292
 293         return false;
 294 }
 295
 296 void TrainRoutePlanner::TrainRoutingState::advance(float distance)
 297 {
 298         offset += distance;
 299         back_offset += distance;
 300
 301         OccupiedTrack *last_occ = occupied_tracks;
 302         for(unsigned n=occupied_tracks->n_tracks; n>1; --n)
 303                 last_occ = last_occ->next;
 304
 305         // XXX What if there's multiple tracks to remove?
 306         if(back_offset>last_occ->path_length)
 307         {
 308                 back_offset -= last_occ->path_length;
 309                 if(occupied_tracks->refcount>1)
 310                 {
 311                         --occupied_tracks->refcount;
 312                         occupied_tracks = new OccupiedTrack(*occupied_tracks);
 313                 }
 314                 --occupied_tracks->n_tracks;
 315         }
 316
 317         distance_traveled += distance;
 318         remaining_estimate -= distance;
 319 }
 320
 321 void TrainRoutePlanner::TrainRoutingState::advance(const Time::TimeDelta &dt)
 322 {
 323         if(delay>=dt)
 324         {
 325                 delay -= dt;
 326                 return;
 327         }
 328
 329         float secs = dt/Time::sec;
 330         if(delay)
 331         {
 332                 secs -= delay/Time::sec;
 333                 delay = Time::zero;
 334         }
 335
 336         if(state==MOVING)
 337                 advance(info->speed*secs);
 338         else if(state!=ARRIVED)
 339                 wait_time += secs*Time::sec;
 340 }
 341
 342 void TrainRoutePlanner::TrainRoutingState::advance_track(unsigned next_path)
 343 {
 344         float distance = occupied_tracks->path_length-offset;
 345         track = track.next(path);
 346         path = next_path;
 347         occupied_tracks = new OccupiedTrack(*track, path, occupied_tracks);
 348         advance(distance);
 349         offset = 0;
 350 }
 351
 352 void TrainRoutePlanner::TrainRoutingState::update_estimate()
 353 {
 354         TrackIter iter = track.reverse(path);
 355         float distance = info->router->get_metric(waypoint).get_distance_from(*iter.track(), iter.entry());
 356         distance += track->get_type().get_path_length(path)-offset;
 357         remaining_estimate = distance;
 358 }
 359
 360
 361 TrainRoutePlanner::RoutingStep::RoutingStep():
 362         prev(0)
 363 { }
 364
 365 TrainRoutePlanner::RoutingStep::RoutingStep(const RoutingStep *p):
 366         time(p->time),
 367         cost_estimate(p->cost_estimate),
 368         trains(p->trains),
 369         prev(p)
 370 { }
 371
 372 void TrainRoutePlanner::RoutingStep::create_successors(list<RoutingStep> &new_steps) const
 373 {
 374         RoutingStep next(this);
 375         if(next.update_states())
 376         {
 377                 if(next.check_deadlocks())
 378                         return;
 379
 380                 new_steps.push_back(next);
 381                 return;
 382         }
 383
 384         int train_index = find_next_train();
 385         if(train_index<0)
 386                 return;
 387
 388         TrainRoutingState &train = next.trains[train_index];
 389
 390         Time::TimeDelta dt = train.get_time_to_next_track();
 391         next.advance(dt);
 392
 393         if(train.check_arrival())
 394         {
 395                 new_steps.push_back(next);
 396                 return;
 397         }
 398
 399         TrackIter next_track = train.track.next(train.path);
 400         train.advance_track(0);
 401
 402         const TrackType::Endpoint &next_entry_ep = next_track.endpoint();
 403         for(unsigned i=0; next_entry_ep.paths>>i; ++i)
 404                 if(next_entry_ep.has_path(i))
 405                 {
 406                         train.path = i;
 407                         train.update_estimate();
 408                         next.update_estimate();
 409                         if(next.is_viable())
 410                                 new_steps.push_back(next);
 411                 }
 412
 413         if(next_entry_ep.paths!=next_track->get_type().get_paths())
 414         {
 415                 RoutingStep wait(this);
 416                 wait.advance(dt);
 417                 wait.trains[train_index].state = WAITING;
 418                 if(wait.is_viable())
 419                         new_steps.push_back(wait);
 420         }
 421 }
 422
 423 bool TrainRoutePlanner::RoutingStep::update_states()
 424 {
 425         bool changes = false;
 426         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 427         {
 428                 if(i->state==ARRIVED)
 429                         continue;
 430
 431                 TrainState old_state = i->state;
 432
 433                 TrackIter next_track = i->track.next(i->path);
 434                 if(next_track)
 435                 {
 436                         i->blocked_by = get_occupant(*next_track);
 437                         if(i->blocked_by>=0)
 438                                 i->state = BLOCKED;
 439                         else if(i->state==BLOCKED)
 440                                 i->state = MOVING;
 441                 }
 442                 else
 443                         i->state = BLOCKED;
 444
 445                 if(i->state!=old_state)
 446                         changes = true;
 447         }
 448
 449         return changes;
 450 }
 451
 452 bool TrainRoutePlanner::RoutingStep::check_deadlocks() const
 453 {
 454         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 455         {
 456                 if(i->state!=BLOCKED)
 457                         continue;
 458
 459                 if(i->blocked_by<0)
 460                         return true;
 461
 462                 int slow = i->blocked_by;
 463                 int fast = trains[slow].blocked_by;
 464                 while(fast>=0 && trains[fast].blocked_by>=0)
 465                 {
 466                         if(fast==slow)
 467                                 return true;
 468
 469                         slow = trains[slow].blocked_by;
 470                         fast = trains[trains[fast].blocked_by].blocked_by;
 471                 }
 472         }
 473
 474         return false;
 475 }
 476
 477 int TrainRoutePlanner::RoutingStep::get_occupant(Track &track) const
 478 {
 479         for(unsigned i=0; i<trains.size(); ++i)
 480                 if(trains[i].is_occupying(track))
 481                         return i;
 482
 483         return -1;
 484 }
 485
 486 int TrainRoutePlanner::RoutingStep::find_next_train() const
 487 {
 488         Time::TimeDelta min_dt;
 489         int next_train = -1;
 490         for(unsigned i=0; i<trains.size(); ++i)
 491                 if(trains[i].state==MOVING)
 492                 {
 493                         Time::TimeDelta dt = trains[i].get_time_to_next_track();
 494                         if(dt<min_dt || next_train<0)
 495                         {
 496                                 min_dt = dt;
 497                                 next_train = i;
 498                         }
 499                 }
 500
 501         return next_train;
 502 }
 503
 504 void TrainRoutePlanner::RoutingStep::advance(const Time::TimeDelta &dt)
 505 {
 506         time += dt;
 507         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 508                 i->advance(dt);
 509 }
 510
 511 void TrainRoutePlanner::RoutingStep::update_estimate()
 512 {
 513         cost_estimate = Time::zero;
 514         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 515                 if(i->remaining_estimate>=0)
 516                         cost_estimate += i->wait_time+((i->distance_traveled+i->remaining_estimate)/i->info->speed)*Time::sec;
 517 }
 518
 519 bool TrainRoutePlanner::RoutingStep::is_viable() const
 520 {
 521         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 522                 if(i->remaining_estimate<0)
 523                         return false;
 524
 525         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 526                 if(i->state==MOVING)
 527                         return true;
 528
 529         return false;
 530 }
 531
 532 bool TrainRoutePlanner::RoutingStep::is_goal() const
 533 {
 534         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 535                 if(i->state!=ARRIVED)
 536                         return false;
 537         return true;
 538 }
 539
 540 bool TrainRoutePlanner::RoutingStep::operator<(const RoutingStep &other) const
 541 {
 542         return cost_estimate<other.cost_estimate;
 543 }
 544
 545 } // namespace R2C2