source/libr2c2/trainrouteplanner.cpp

   1 #include <msp/core/maputils.h>
   2 #include "catalogue.h"
   3 #include "layout.h"
   4 #include "route.h"
   5 #include "train.h"
   6 #include "trainroutemetric.h"
   7 #include "trainrouteplanner.h"
   8 #include "trainrouter.h"
   9 #include "vehicle.h"
  10
  11 using namespace std;
  12 using namespace Msp;
  13
  14 namespace R2C2 {
  15
  16 TrainRoutePlanner::TrainRoutePlanner(Layout &layout):
  17         goal(0),
  18         result(PENDING),
  19         thread(0)
  20 {
  21         const map<unsigned, Train *> &trains = layout.get_trains();
  22         for(map<unsigned, Train *>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
  23         {
  24                 TrainRoutingInfo info(*i->second);
  25                 if(info.destination)
  26                         routed_trains.push_back(info);
  27         }
  28 }
  29
  30 TrainRoutePlanner::~TrainRoutePlanner()
  31 {
  32         if(thread)
  33         {
  34                 thread->join();
  35                 delete thread;
  36         }
  37 }
  38
  39 TrainRoutePlanner::Result TrainRoutePlanner::plan()
  40 {
  41         prepare_plan();
  42         create_plan();
  43         if(result==PENDING)
  44                 finalize_plan();
  45
  46         return result;
  47 }
  48
  49 void TrainRoutePlanner::plan_async()
  50 {
  51         if(thread)
  52                 throw logic_error("already planning");
  53
  54         prepare_plan();
  55         thread = new PlanningThread(*this);
  56 }
  57
  58 TrainRoutePlanner::Result TrainRoutePlanner::check()
  59 {
  60         if(result==PENDING && goal)
  61         {
  62                 if(thread)
  63                 {
  64                         thread->join();
  65                         delete thread;
  66                         thread = 0;
  67                 }
  68                 finalize_plan();
  69         }
  70
  71         return result;
  72 }
  73
  74 const list<Route *> &TrainRoutePlanner::get_routes_for(const Train &train) const
  75 {
  76         return get_train_info(train).routes;
  77 }
  78
  79 const list<TrainRouter::SequencePoint> &TrainRoutePlanner::get_sequence_for(const Train &train) const
  80 {
  81         return get_train_info(train).sequence;
  82 }
  83
  84 const TrainRoutePlanner::TrainRoutingInfo &TrainRoutePlanner::get_train_info(const Train &train) const
  85 {
  86         for(vector<TrainRoutingInfo>::const_iterator i=routed_trains.begin(); i!=routed_trains.end(); ++i)
  87                 if(i->train==&train)
  88                         return *i;
  89
  90         throw key_error(train.get_name());
  91 }
  92
  93 const TrainRoutePlanner::RoutingStep &TrainRoutePlanner::get_step()
  94 {
  95         steps.splice(steps.end(), queue, queue.begin());
  96         return steps.back();
  97 }
  98
  99 void TrainRoutePlanner::prepare_plan()
 100 {
 101         steps.clear();
 102         queue.clear();
 103         goal = 0;
 104         result = PENDING;
 105
 106         queue.push_back(RoutingStep());
 107         RoutingStep &start = queue.back();
 108         for(vector<TrainRoutingInfo>::iterator i=routed_trains.begin(); i!=routed_trains.end(); ++i)
 109                 start.trains.push_back(TrainRoutingState(*i));
 110         start.update_estimate();
 111 }
 112
 113 void TrainRoutePlanner::create_plan()
 114 {
 115         while(!queue.empty())
 116         {
 117                 const RoutingStep &step = get_step();
 118                 if(step.is_goal())
 119                 {
 120                         goal = &step;
 121                         return;
 122                 }
 123
 124                 add_steps(step);
 125         }
 126
 127         result = FAILED;
 128 }
 129
 130 void TrainRoutePlanner::add_steps(const RoutingStep &step)
 131 {
 132         list<RoutingStep> new_steps;
 133         step.create_successors(new_steps);
 134         new_steps.sort();
 135         queue.merge(new_steps);
 136 }
 137
 138 void TrainRoutePlanner::finalize_plan()
 139 {
 140         for(vector<TrainRoutingInfo>::iterator i=routed_trains.begin(); i!=routed_trains.end(); ++i)
 141         {
 142                 i->routes.clear();
 143                 i->sequence.clear();
 144                 for(unsigned j=0; j<2; ++j)
 145                         i->track_history[j] = 0;
 146         }
 147
 148         map<Track *, TrainRouter::SequencePoint *> sequenced_tracks;
 149         unsigned sequence = steps.size();
 150         for(const RoutingStep *i=goal; i; i=i->prev)
 151                 for(vector<TrainRoutingState>::const_iterator j=i->trains.begin(); j!=i->trains.end(); ++j)
 152                 {
 153                         Track **history = j->info->track_history;
 154                         if(j->track.track()==history[0])
 155                                 continue;
 156
 157                         Route *route = 0;
 158                         bool start_new_route = true;
 159                         if(!j->info->routes.empty())
 160                         {
 161                                 route = j->info->routes.front();
 162                                 start_new_route = route->has_track(*j->track);
 163                                 if(!start_new_route)
 164                                 {
 165                                         unsigned nls = j->track->get_n_link_slots();
 166                                         for(unsigned k=0; (!start_new_route && k<nls); ++k)
 167                                         {
 168                                                 Track *link = j->track->get_link(k);
 169                                                 start_new_route = (link && link!=history[0] && route->has_track(*link));
 170                                         }
 171                                 }
 172                         }
 173
 174                         if(start_new_route)
 175                         {
 176                                 route = new Route(j->info->train->get_layout());
 177                                 route->set_name("Router");
 178                                 route->set_temporary(true);
 179                                 for(unsigned k=0; (k<2 && history[k]); ++k)
 180                                         route->add_track(*history[k]);
 181                                 j->info->routes.push_front(route);
 182                         }
 183
 184                         route->add_track(*j->track.track());
 185                         history[1] = history[0];
 186                         history[0] = j->track.track();
 187
 188                         bool waitable = j->track.endpoint().paths!=j->track->get_type().get_paths();
 189                         map<Track *, TrainRouter::SequencePoint *>::iterator k = sequenced_tracks.find(j->track.track());
 190                         if(k!=sequenced_tracks.end())
 191                         {
 192                                 if(!k->second->preceding_train)
 193                                 {
 194                                         k->second->preceding_train = j->info->train;
 195                                         k->second->sequence_in = sequence;
 196                                 }
 197                                 j->info->sequence.push_front(TrainRouter::SequencePoint(j->track->get_block(), sequence));
 198                                 if(waitable)
 199                                         k->second = &j->info->sequence.front();
 200                                 --sequence;
 201                         }
 202                         else if(waitable)
 203                         {
 204                                 j->info->sequence.push_front(TrainRouter::SequencePoint(j->track->get_block(), sequence));
 205                                 sequenced_tracks[j->track.track()] = &j->info->sequence.front();
 206                                 --sequence;
 207                         }
 208                 }
 209
 210         result = COMPLETE;
 211 }
 212
 213
 214 TrainRoutePlanner::TrainRoutingInfo::TrainRoutingInfo(Train &t):
 215         train(&t),
 216         speed(train->get_maximum_speed()),
 217         router(train->get_ai_of_type<TrainRouter>()),
 218         destination(0),
 219         has_duration(false)
 220 {
 221         if(router)
 222         {
 223                 destination = router->get_destination();
 224                 if(destination)
 225                 {
 226                         waypoints.resize(router->get_n_waypoints());
 227                         metrics.resize(waypoints.size()+1);
 228                         metrics[0] = &router->get_metric(-1);
 229                         for(unsigned i=0; i<waypoints.size(); ++i)
 230                         {
 231                                 waypoints[i] = &router->get_waypoint(i);
 232                                 metrics[i+1] = &router->get_metric(i);
 233                         }
 234                         has_duration = router->get_trip_duration();
 235                 }
 236         }
 237
 238         // If no maximum speed is specified, use a sensible default
 239         if(!speed)
 240                 speed = 20*train->get_layout().get_catalogue().get_scale();
 241 }
 242
 243
 244 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(Track &t, unsigned p, OccupiedTrack *n):
 245         track(&t),
 246         path_length(track->get_type().get_path_length(p)),
 247         next(n),
 248         n_tracks(next ? next->n_tracks+1 : 1),
 249         refcount(1)
 250 {
 251         if(next)
 252                 ++next->refcount;
 253 }
 254
 255 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(const OccupiedTrack &other):
 256         track(other.track),
 257         path_length(other.path_length),
 258         next(other.next),
 259         n_tracks(other.n_tracks),
 260         refcount(1)
 261 {
 262         if(next)
 263                 ++next->refcount;
 264 }
 265
 266 TrainRoutePlanner::OccupiedTrack::~OccupiedTrack()
 267 {
 268         if(next && !--next->refcount)
 269                 delete next;
 270 }
 271
 272
 273 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(TrainRoutingInfo &inf):
 274         info(&inf),
 275         occupied_tracks(0),
 276         state(MOVING),
 277         delay(info->router->get_departure_delay()),
 278         duration(info->router->get_trip_duration()),
 279         waypoint(info->waypoints.empty() ? -1 : 0),
 280         blocked_by(-1)
 281 {
 282         const Vehicle *veh = &info->train->get_vehicle(0);
 283         // TODO margins
 284         TrackOffsetIter track_and_offs = veh->get_placement().get_position(VehiclePlacement::FRONT_BUFFER);
 285         track = track_and_offs.track_iter();
 286         offset = track_and_offs.offset();
 287         path = track->get_active_path();
 288
 289         while(Vehicle *next = veh->get_link(1))
 290                 veh = next;
 291         track_and_offs = veh->get_placement().get_position(VehiclePlacement::BACK_BUFFER);
 292         back_offset = track_and_offs.offset();
 293
 294         TrackIter iter = track_and_offs.track_iter();
 295         while(1)
 296         {
 297                 occupied_tracks = new OccupiedTrack(*iter, iter->get_active_path(), occupied_tracks);
 298                 if(iter.track()==track.track())
 299                         break;
 300                 iter = iter.next();
 301         }
 302
 303         update_estimate();
 304 }
 305
 306 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(const TrainRoutingState &other):
 307         info(other.info),
 308         track(other.track),
 309         path(other.path),
 310         occupied_tracks(other.occupied_tracks),
 311         offset(other.offset),
 312         back_offset(other.back_offset),
 313         state(other.state),
 314         delay(other.delay),
 315         duration(other.duration),
 316         waypoint(other.waypoint),
 317         distance_traveled(other.distance_traveled),
 318         remaining_estimate(other.remaining_estimate),
 319         wait_time(other.wait_time),
 320         blocked_by(other.blocked_by)
 321 {
 322         ++occupied_tracks->refcount;
 323 }
 324
 325 TrainRoutePlanner::TrainRoutingState::~TrainRoutingState()
 326 {
 327         if(occupied_tracks && !--occupied_tracks->refcount)
 328                 delete occupied_tracks;
 329 }
 330
 331 Time::TimeDelta TrainRoutePlanner::TrainRoutingState::get_time_to_next_track() const
 332 {
 333         return ((track->get_type().get_path_length(path)-offset)/info->speed)*Time::sec+delay;
 334 }
 335
 336 bool TrainRoutePlanner::TrainRoutingState::is_occupying(Track &trk) const
 337 {
 338         if(state==ARRIVED && !duration && info->has_duration)
 339                 return false;
 340
 341         OccupiedTrack *occ = occupied_tracks;
 342         for(unsigned n=occ->n_tracks; n>0; --n, occ=occ->next)
 343                 if(occ->track==&trk)
 344                         return true;
 345         return false;
 346 }
 347
 348 bool TrainRoutePlanner::TrainRoutingState::check_arrival()
 349 {
 350         TrackIter next_track = track.next(path);
 351
 352         if(waypoint<0 && info->destination->has_track(*track) && !info->destination->has_track(*next_track))
 353         {
 354                 state = ARRIVED;
 355                 return true;
 356         }
 357         else if(waypoint>=0 && info->waypoints[waypoint]->has_track(*track) && !info->waypoints[waypoint]->has_track(*next_track))
 358         {
 359                 ++waypoint;
 360                 if(waypoint>=static_cast<int>(info->waypoints.size()))
 361                         waypoint = -1;
 362         }
 363
 364         return false;
 365 }
 366
 367 void TrainRoutePlanner::TrainRoutingState::advance(float distance)
 368 {
 369         offset += distance;
 370         back_offset += distance;
 371
 372         OccupiedTrack *last_occ = occupied_tracks;
 373         for(unsigned n=occupied_tracks->n_tracks; n>1; --n)
 374                 last_occ = last_occ->next;
 375
 376         // XXX What if there's multiple tracks to remove?
 377         if(back_offset>last_occ->path_length)
 378         {
 379                 back_offset -= last_occ->path_length;
 380                 if(occupied_tracks->refcount>1)
 381                 {
 382                         --occupied_tracks->refcount;
 383                         occupied_tracks = new OccupiedTrack(*occupied_tracks);
 384                 }
 385                 --occupied_tracks->n_tracks;
 386         }
 387
 388         distance_traveled += distance;
 389         remaining_estimate -= distance;
 390 }
 391
 392 void TrainRoutePlanner::TrainRoutingState::advance(const Time::TimeDelta &dt)
 393 {
 394         if(delay>=dt)
 395         {
 396                 delay -= dt;
 397                 return;
 398         }
 399
 400         float secs = dt/Time::sec;
 401         if(delay)
 402         {
 403                 secs -= delay/Time::sec;
 404                 delay = Time::zero;
 405         }
 406
 407         if(duration)
 408                 duration = max(duration-secs*Time::sec, Time::zero);
 409
 410         if(state==MOVING)
 411                 advance(info->speed*secs);
 412         else if(state!=ARRIVED)
 413                 wait_time += secs*Time::sec;
 414 }
 415
 416 void TrainRoutePlanner::TrainRoutingState::advance_track(unsigned next_path)
 417 {
 418         float distance = occupied_tracks->path_length-offset;
 419         track = track.next(path);
 420         path = next_path;
 421         occupied_tracks = new OccupiedTrack(*track, path, occupied_tracks);
 422         advance(distance);
 423         offset = 0;
 424 }
 425
 426 void TrainRoutePlanner::TrainRoutingState::update_estimate()
 427 {
 428         TrackIter iter = track.reverse(path);
 429         float distance = info->metrics[waypoint+1]->get_distance_from(*iter.track(), iter.entry());
 430         distance += track->get_type().get_path_length(path)-offset;
 431         remaining_estimate = distance;
 432 }
 433
 434
 435 TrainRoutePlanner::RoutingStep::RoutingStep():
 436         prev(0)
 437 { }
 438
 439 TrainRoutePlanner::RoutingStep::RoutingStep(const RoutingStep *p):
 440         time(p->time),
 441         penalty(p->penalty),
 442         cost_estimate(p->cost_estimate),
 443         trains(p->trains),
 444         prev(p)
 445 { }
 446
 447 void TrainRoutePlanner::RoutingStep::create_successors(list<RoutingStep> &new_steps) const
 448 {
 449         RoutingStep next(this);
 450         if(next.update_states())
 451         {
 452                 if(next.check_deadlocks())
 453                         return;
 454
 455                 new_steps.push_back(next);
 456                 return;
 457         }
 458
 459         int train_index = find_next_train();
 460         if(train_index<0)
 461                 return;
 462
 463         TrainRoutingState &train = next.trains[train_index];
 464
 465         Time::TimeDelta dt = train.get_time_to_next_track();
 466         next.advance(dt);
 467
 468         if(train.check_arrival())
 469         {
 470                 new_steps.push_back(next);
 471                 return;
 472         }
 473
 474         TrackIter next_track = train.track.next(train.path);
 475         train.advance_track(0);
 476
 477         const TrackType::Endpoint &next_entry_ep = next_track.endpoint();
 478         for(unsigned i=0; next_entry_ep.paths>>i; ++i)
 479                 if(next_entry_ep.has_path(i))
 480                 {
 481                         train.path = i;
 482                         train.update_estimate();
 483                         next.update_estimate();
 484                         if(next.is_viable())
 485                                 new_steps.push_back(next);
 486                 }
 487
 488         new_steps.sort();
 489         for(list<RoutingStep>::iterator i=new_steps.begin(); ++i!=new_steps.end(); )
 490         {
 491                 i->penalty += 5*Time::sec;
 492                 i->update_estimate();
 493         }
 494
 495         if(next_entry_ep.paths!=next_track->get_type().get_paths())
 496         {
 497                 RoutingStep wait(this);
 498                 wait.advance(dt);
 499                 wait.trains[train_index].state = WAITING;
 500                 wait.penalty += 15*Time::sec;
 501                 wait.update_estimate();
 502                 if(wait.is_viable())
 503                         new_steps.push_back(wait);
 504         }
 505 }
 506
 507 bool TrainRoutePlanner::RoutingStep::update_states()
 508 {
 509         bool changes = false;
 510         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 511         {
 512                 if(i->state==ARRIVED)
 513                         continue;
 514
 515                 TrainState old_state = i->state;
 516
 517                 TrackIter next_track = i->track.next(i->path);
 518                 if(next_track)
 519                 {
 520                         i->blocked_by = get_occupant(*next_track);
 521                         if(i->blocked_by>=0)
 522                                 i->state = BLOCKED;
 523                         else if(i->state==BLOCKED)
 524                                 i->state = MOVING;
 525                 }
 526                 else
 527                         i->state = BLOCKED;
 528
 529                 if(i->state!=old_state)
 530                         changes = true;
 531         }
 532
 533         return changes;
 534 }
 535
 536 bool TrainRoutePlanner::RoutingStep::check_deadlocks() const
 537 {
 538         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 539         {
 540                 if(i->state!=BLOCKED)
 541                         continue;
 542
 543                 if(i->blocked_by<0)
 544                         return true;
 545
 546                 int slow = i->blocked_by;
 547                 int fast = trains[slow].blocked_by;
 548                 while(fast>=0 && trains[fast].blocked_by>=0)
 549                 {
 550                         if(fast==slow)
 551                                 return true;
 552
 553                         slow = trains[slow].blocked_by;
 554                         fast = trains[trains[fast].blocked_by].blocked_by;
 555                 }
 556         }
 557
 558         return false;
 559 }
 560
 561 int TrainRoutePlanner::RoutingStep::get_occupant(Track &track) const
 562 {
 563         for(unsigned i=0; i<trains.size(); ++i)
 564                 if(trains[i].is_occupying(track))
 565                         return i;
 566
 567         return -1;
 568 }
 569
 570 int TrainRoutePlanner::RoutingStep::find_next_train() const
 571 {
 572         Time::TimeDelta min_dt;
 573         int next_train = -1;
 574         for(unsigned i=0; i<trains.size(); ++i)
 575                 if(trains[i].state==MOVING)
 576                 {
 577                         Time::TimeDelta dt = trains[i].get_time_to_next_track();
 578                         if(dt<min_dt || next_train<0)
 579                         {
 580                                 min_dt = dt;
 581                                 next_train = i;
 582                         }
 583                 }
 584
 585         return next_train;
 586 }
 587
 588 void TrainRoutePlanner::RoutingStep::advance(const Time::TimeDelta &dt)
 589 {
 590         time += dt;
 591         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 592                 i->advance(dt);
 593 }
 594
 595 void TrainRoutePlanner::RoutingStep::update_estimate()
 596 {
 597         cost_estimate = penalty;
 598         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 599                 if(i->remaining_estimate>=0)
 600                         cost_estimate += i->wait_time+((i->distance_traveled+i->remaining_estimate)/i->info->speed)*Time::sec;
 601 }
 602
 603 bool TrainRoutePlanner::RoutingStep::is_viable() const
 604 {
 605         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 606                 if(i->remaining_estimate<0)
 607                         return false;
 608
 609         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 610                 if(i->state==MOVING)
 611                         return true;
 612
 613         return false;
 614 }
 615
 616 bool TrainRoutePlanner::RoutingStep::is_goal() const
 617 {
 618         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 619                 if(i->state!=ARRIVED)
 620                         return false;
 621         return true;
 622 }
 623
 624 bool TrainRoutePlanner::RoutingStep::operator<(const RoutingStep &other) const
 625 {
 626         return cost_estimate<other.cost_estimate;
 627 }
 628
 629
 630 TrainRoutePlanner::PlanningThread::PlanningThread(TrainRoutePlanner &p):
 631         planner(p)
 632 {
 633         launch();
 634 }
 635
 636 void TrainRoutePlanner::PlanningThread::main()
 637 {
 638         planner.create_plan();
 639 }
 640
 641 } // namespace R2C2