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