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         first_noncritical(train->get_first_noncritical_block().block()),
 218         router(train->get_ai_of_type<TrainRouter>()),
 219         destination(0),
 220         has_duration(false)
 221 {
 222         if(router)
 223         {
 224                 destination = router->get_destination();
 225                 if(destination)
 226                 {
 227                         waypoints.resize(router->get_n_waypoints());
 228                         metrics.resize(waypoints.size()+1);
 229                         metrics[0] = &router->get_metric(-1);
 230                         for(unsigned i=0; i<waypoints.size(); ++i)
 231                         {
 232                                 waypoints[i] = &router->get_waypoint(i);
 233                                 metrics[i+1] = &router->get_metric(i);
 234                         }
 235                         has_duration = router->get_trip_duration();
 236                 }
 237         }
 238
 239         // If no maximum speed is specified, use a sensible default
 240         if(!speed)
 241                 speed = 20*train->get_layout().get_catalogue().get_scale();
 242 }
 243
 244
 245 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(Track &t, unsigned p, OccupiedTrack *n):
 246         track(&t),
 247         path_length(track->get_type().get_path_length(p)),
 248         next(n),
 249         n_tracks(next ? next->n_tracks+1 : 1),
 250         refcount(1)
 251 {
 252         if(next)
 253                 ++next->refcount;
 254 }
 255
 256 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(const OccupiedTrack &other):
 257         track(other.track),
 258         path_length(other.path_length),
 259         next(other.next),
 260         n_tracks(other.n_tracks),
 261         refcount(1)
 262 {
 263         if(next)
 264                 ++next->refcount;
 265 }
 266
 267 TrainRoutePlanner::OccupiedTrack::~OccupiedTrack()
 268 {
 269         if(next && !--next->refcount)
 270                 delete next;
 271 }
 272
 273
 274 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(TrainRoutingInfo &inf):
 275         info(&inf),
 276         critical(true),
 277         occupied_tracks(0),
 278         state(MOVING),
 279         delay(info->router->get_departure_delay()),
 280         duration(info->router->get_trip_duration()),
 281         waypoint(info->waypoints.empty() ? -1 : 0),
 282         blocked_by(-1)
 283 {
 284         const Vehicle *veh = &info->train->get_vehicle(0);
 285         // TODO margins
 286         TrackOffsetIter track_and_offs = veh->get_placement().get_position(VehiclePlacement::FRONT_BUFFER);
 287         track = track_and_offs.track_iter();
 288         offset = track_and_offs.offset();
 289         path = track->get_active_path();
 290
 291         while(Vehicle *next = veh->get_link(1))
 292                 veh = next;
 293         track_and_offs = veh->get_placement().get_position(VehiclePlacement::BACK_BUFFER);
 294         back_offset = track_and_offs.offset();
 295
 296         TrackIter iter = track_and_offs.track_iter();
 297         while(1)
 298         {
 299                 occupied_tracks = new OccupiedTrack(*iter, iter->get_active_path(), occupied_tracks);
 300                 if(iter.track()==track.track())
 301                         break;
 302                 iter = iter.next();
 303         }
 304
 305         update_estimate();
 306 }
 307
 308 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(const TrainRoutingState &other):
 309         info(other.info),
 310         track(other.track),
 311         path(other.path),
 312         critical(other.critical),
 313         occupied_tracks(other.occupied_tracks),
 314         offset(other.offset),
 315         back_offset(other.back_offset),
 316         state(other.state),
 317         delay(other.delay),
 318         duration(other.duration),
 319         waypoint(other.waypoint),
 320         distance_traveled(other.distance_traveled),
 321         remaining_estimate(other.remaining_estimate),
 322         wait_time(other.wait_time),
 323         blocked_by(other.blocked_by)
 324 {
 325         ++occupied_tracks->refcount;
 326 }
 327
 328 TrainRoutePlanner::TrainRoutingState::~TrainRoutingState()
 329 {
 330         if(occupied_tracks && !--occupied_tracks->refcount)
 331                 delete occupied_tracks;
 332 }
 333
 334 Time::TimeDelta TrainRoutePlanner::TrainRoutingState::get_time_to_next_track() const
 335 {
 336         return ((track->get_type().get_path_length(path)-offset)/info->speed)*Time::sec+delay;
 337 }
 338
 339 bool TrainRoutePlanner::TrainRoutingState::is_occupying(Track &trk) const
 340 {
 341         if(state==ARRIVED && !duration && info->has_duration)
 342                 return false;
 343
 344         OccupiedTrack *occ = occupied_tracks;
 345         for(unsigned n=occ->n_tracks; n>0; --n, occ=occ->next)
 346                 if(occ->track==&trk)
 347                         return true;
 348         return false;
 349 }
 350
 351 bool TrainRoutePlanner::TrainRoutingState::check_arrival()
 352 {
 353         TrackIter next_track = track.next(path);
 354
 355         if(waypoint<0 && info->destination->has_track(*track) && !info->destination->has_track(*next_track))
 356         {
 357                 state = ARRIVED;
 358                 return true;
 359         }
 360         else if(waypoint>=0 && info->waypoints[waypoint]->has_track(*track) && !info->waypoints[waypoint]->has_track(*next_track))
 361         {
 362                 ++waypoint;
 363                 if(waypoint>=static_cast<int>(info->waypoints.size()))
 364                         waypoint = -1;
 365         }
 366
 367         if(info->first_noncritical->has_track(*track))
 368                 critical = false;
 369
 370         return false;
 371 }
 372
 373 void TrainRoutePlanner::TrainRoutingState::advance(float distance)
 374 {
 375         offset += distance;
 376         back_offset += distance;
 377
 378         OccupiedTrack *last_occ = occupied_tracks;
 379         for(unsigned n=occupied_tracks->n_tracks; n>1; --n)
 380                 last_occ = last_occ->next;
 381
 382         // XXX What if there's multiple tracks to remove?
 383         if(back_offset>last_occ->path_length)
 384         {
 385                 back_offset -= last_occ->path_length;
 386                 if(occupied_tracks->refcount>1)
 387                 {
 388                         --occupied_tracks->refcount;
 389                         occupied_tracks = new OccupiedTrack(*occupied_tracks);
 390                 }
 391                 --occupied_tracks->n_tracks;
 392         }
 393
 394         distance_traveled += distance;
 395         remaining_estimate -= distance;
 396 }
 397
 398 void TrainRoutePlanner::TrainRoutingState::advance(const Time::TimeDelta &dt)
 399 {
 400         if(delay>=dt)
 401         {
 402                 delay -= dt;
 403                 return;
 404         }
 405
 406         float secs = dt/Time::sec;
 407         if(delay)
 408         {
 409                 secs -= delay/Time::sec;
 410                 delay = Time::zero;
 411         }
 412
 413         if(duration)
 414                 duration = max(duration-secs*Time::sec, Time::zero);
 415
 416         if(state==MOVING)
 417                 advance(info->speed*secs);
 418         else if(state!=ARRIVED)
 419                 wait_time += secs*Time::sec;
 420 }
 421
 422 void TrainRoutePlanner::TrainRoutingState::advance_track(unsigned next_path)
 423 {
 424         float distance = occupied_tracks->path_length-offset;
 425         track = track.next(path);
 426         path = next_path;
 427         occupied_tracks = new OccupiedTrack(*track, path, occupied_tracks);
 428         advance(distance);
 429         offset = 0;
 430 }
 431
 432 void TrainRoutePlanner::TrainRoutingState::update_estimate()
 433 {
 434         TrackIter iter = track.reverse(path);
 435         float distance = info->metrics[waypoint+1]->get_distance_from(*iter.track(), iter.entry());
 436         distance += track->get_type().get_path_length(path)-offset;
 437         remaining_estimate = distance;
 438 }
 439
 440
 441 TrainRoutePlanner::RoutingStep::RoutingStep():
 442         prev(0)
 443 { }
 444
 445 TrainRoutePlanner::RoutingStep::RoutingStep(const RoutingStep *p):
 446         time(p->time),
 447         penalty(p->penalty),
 448         cost_estimate(p->cost_estimate),
 449         trains(p->trains),
 450         prev(p)
 451 { }
 452
 453 void TrainRoutePlanner::RoutingStep::create_successors(list<RoutingStep> &new_steps) const
 454 {
 455         RoutingStep next(this);
 456         if(next.update_states())
 457         {
 458                 if(next.check_deadlocks())
 459                         return;
 460
 461                 new_steps.push_back(next);
 462                 return;
 463         }
 464
 465         int train_index = find_next_train();
 466         if(train_index<0)
 467                 return;
 468
 469         TrainRoutingState &train = next.trains[train_index];
 470
 471         Time::TimeDelta dt = train.get_time_to_next_track();
 472         next.advance(dt);
 473
 474         if(train.check_arrival())
 475         {
 476                 new_steps.push_back(next);
 477                 return;
 478         }
 479
 480         TrackIter next_track = train.track.next(train.path);
 481         train.advance_track(0);
 482
 483         const TrackType::Endpoint &next_entry_ep = next_track.endpoint();
 484         if(train.critical)
 485         {
 486                 train.path = train.track->get_type().coerce_path(train.track.entry(), train.track->get_active_path());
 487                 train.update_estimate();
 488                 next.update_estimate();
 489                 if(next.is_viable())
 490                         new_steps.push_back(next);
 491         }
 492         else
 493         {
 494                 for(unsigned i=0; next_entry_ep.paths>>i; ++i)
 495                         if(next_entry_ep.has_path(i))
 496                         {
 497                                 train.path = i;
 498                                 train.update_estimate();
 499                                 next.update_estimate();
 500                                 if(next.is_viable())
 501                                         new_steps.push_back(next);
 502                         }
 503         }
 504
 505         new_steps.sort();
 506         for(list<RoutingStep>::iterator i=new_steps.begin(); ++i!=new_steps.end(); )
 507         {
 508                 i->penalty += 5*Time::sec;
 509                 i->update_estimate();
 510         }
 511
 512         if(next_entry_ep.paths!=next_track->get_type().get_paths() && !train.critical)
 513         {
 514                 RoutingStep wait(this);
 515                 wait.advance(dt);
 516                 wait.trains[train_index].state = WAITING;
 517                 wait.penalty += 15*Time::sec;
 518                 wait.update_estimate();
 519                 if(wait.is_viable())
 520                         new_steps.push_back(wait);
 521         }
 522 }
 523
 524 bool TrainRoutePlanner::RoutingStep::update_states()
 525 {
 526         bool changes = false;
 527         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 528         {
 529                 if(i->state==ARRIVED)
 530                         continue;
 531
 532                 TrainState old_state = i->state;
 533
 534                 TrackIter next_track = i->track.next(i->path);
 535                 if(next_track)
 536                 {
 537                         i->blocked_by = get_occupant(*next_track);
 538                         if(i->blocked_by>=0)
 539                                 i->state = BLOCKED;
 540                         else if(i->state==BLOCKED)
 541                                 i->state = MOVING;
 542                 }
 543                 else
 544                         i->state = BLOCKED;
 545
 546                 if(i->state!=old_state)
 547                         changes = true;
 548         }
 549
 550         return changes;
 551 }
 552
 553 bool TrainRoutePlanner::RoutingStep::check_deadlocks() const
 554 {
 555         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 556         {
 557                 if(i->state!=BLOCKED)
 558                         continue;
 559
 560                 if(i->blocked_by<0)
 561                         return true;
 562
 563                 int slow = i->blocked_by;
 564                 int fast = trains[slow].blocked_by;
 565                 while(fast>=0 && trains[fast].blocked_by>=0)
 566                 {
 567                         if(fast==slow)
 568                                 return true;
 569
 570                         slow = trains[slow].blocked_by;
 571                         fast = trains[trains[fast].blocked_by].blocked_by;
 572                 }
 573         }
 574
 575         return false;
 576 }
 577
 578 int TrainRoutePlanner::RoutingStep::get_occupant(Track &track) const
 579 {
 580         for(unsigned i=0; i<trains.size(); ++i)
 581                 if(trains[i].is_occupying(track))
 582                         return i;
 583
 584         return -1;
 585 }
 586
 587 int TrainRoutePlanner::RoutingStep::find_next_train() const
 588 {
 589         Time::TimeDelta min_dt;
 590         int next_train = -1;
 591         for(unsigned i=0; i<trains.size(); ++i)
 592                 if(trains[i].state==MOVING)
 593                 {
 594                         Time::TimeDelta dt = trains[i].get_time_to_next_track();
 595                         if(dt<min_dt || next_train<0)
 596                         {
 597                                 min_dt = dt;
 598                                 next_train = i;
 599                         }
 600                 }
 601
 602         return next_train;
 603 }
 604
 605 void TrainRoutePlanner::RoutingStep::advance(const Time::TimeDelta &dt)
 606 {
 607         time += dt;
 608         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 609                 i->advance(dt);
 610 }
 611
 612 void TrainRoutePlanner::RoutingStep::update_estimate()
 613 {
 614         cost_estimate = penalty;
 615         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 616                 if(i->remaining_estimate>=0)
 617                         cost_estimate += i->wait_time+((i->distance_traveled+i->remaining_estimate)/i->info->speed)*Time::sec;
 618 }
 619
 620 bool TrainRoutePlanner::RoutingStep::is_viable() const
 621 {
 622         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 623                 if(i->remaining_estimate<0)
 624                         return false;
 625
 626         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 627                 if(i->state==MOVING)
 628                         return true;
 629
 630         return false;
 631 }
 632
 633 bool TrainRoutePlanner::RoutingStep::is_goal() const
 634 {
 635         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 636                 if(i->state!=ARRIVED)
 637                         return false;
 638         return true;
 639 }
 640
 641 bool TrainRoutePlanner::RoutingStep::operator<(const RoutingStep &other) const
 642 {
 643         return cost_estimate<other.cost_estimate;
 644 }
 645
 646
 647 TrainRoutePlanner::PlanningThread::PlanningThread(TrainRoutePlanner &p):
 648         planner(p)
 649 {
 650         launch();
 651 }
 652
 653 void TrainRoutePlanner::PlanningThread::main()
 654 {
 655         planner.create_plan();
 656 }
 657
 658 } // namespace R2C2