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<3; ++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=2; k>0; --k)
 172                                         if(history[k])
 173                                                 route->add_track(*history[k]);
 174                                 j->info->routes.push_front(route);
 175                         }
 176
 177                         if(history[0])
 178                                 route->add_track(*history[0]);
 179                         for(unsigned k=2; k>0; --k)
 180                                 history[k] = history[k-1];
 181                         history[0] = j->track.track();
 182
 183                         bool waitable = j->track.endpoint().paths!=j->track->get_type().get_paths();
 184                         map<Track *, TrainRouter::SequencePoint *>::iterator k = sequenced_tracks.find(j->track.track());
 185                         if(k!=sequenced_tracks.end())
 186                         {
 187                                 if(!k->second->preceding_train)
 188                                 {
 189                                         k->second->preceding_train = j->info->train;
 190                                         k->second->sequence_in = sequence;
 191                                 }
 192                                 j->info->sequence.push_front(TrainRouter::SequencePoint(j->track->get_block(), sequence));
 193                                 if(waitable)
 194                                         k->second = &j->info->sequence.front();
 195                                 --sequence;
 196                         }
 197                         else if(waitable)
 198                         {
 199                                 j->info->sequence.push_front(TrainRouter::SequencePoint(j->track->get_block(), sequence));
 200                                 sequenced_tracks[j->track.track()] = &j->info->sequence.front();
 201                                 --sequence;
 202                         }
 203                 }
 204
 205         result = COMPLETE;
 206 }
 207
 208
 209 TrainRoutePlanner::TrainRoutingInfo::TrainRoutingInfo(Train &t):
 210         train(&t),
 211         speed(train->get_maximum_speed()),
 212         router(train->get_ai_of_type<TrainRouter>())
 213 {
 214         // If no maximum speed is specified, use a sensible default
 215         if(!speed)
 216                 speed = 20*train->get_layout().get_catalogue().get_scale();
 217 }
 218
 219
 220 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(Track &t, unsigned p, OccupiedTrack *n):
 221         track(&t),
 222         path_length(track->get_type().get_path_length(p)),
 223         next(n),
 224         n_tracks(next ? next->n_tracks+1 : 1),
 225         refcount(1)
 226 {
 227         if(next)
 228                 ++next->refcount;
 229 }
 230
 231 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(const OccupiedTrack &other):
 232         track(other.track),
 233         path_length(other.path_length),
 234         next(other.next),
 235         n_tracks(other.n_tracks),
 236         refcount(1)
 237 {
 238         if(next)
 239                 ++next->refcount;
 240 }
 241
 242 TrainRoutePlanner::OccupiedTrack::~OccupiedTrack()
 243 {
 244         if(next && !--next->refcount)
 245                 delete next;
 246 }
 247
 248
 249 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(TrainRoutingInfo &inf):
 250         info(&inf),
 251         occupied_tracks(0),
 252         state(MOVING),
 253         delay(info->router->get_departure_delay()),
 254         waypoint(info->router->get_n_waypoints() ? 0 : -1),
 255         blocked_by(-1)
 256 {
 257         const Vehicle *veh = &info->train->get_vehicle(0);
 258         // TODO margins
 259         TrackOffsetIter track_and_offs = veh->get_placement().get_position(VehiclePlacement::FRONT_BUFFER);
 260         track = track_and_offs.track_iter();
 261         offset = track_and_offs.offset();
 262         path = track->get_active_path();
 263
 264         while(Vehicle *next = veh->get_link(1))
 265                 veh = next;
 266         track_and_offs = veh->get_placement().get_position(VehiclePlacement::BACK_BUFFER);
 267         back_offset = track_and_offs.offset();
 268
 269         TrackIter iter = track_and_offs.track_iter();
 270         while(1)
 271         {
 272                 occupied_tracks = new OccupiedTrack(*iter, iter->get_active_path(), occupied_tracks);
 273                 if(iter.track()==track.track())
 274                         break;
 275                 iter = iter.next();
 276         }
 277
 278         update_estimate();
 279 }
 280
 281 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(const TrainRoutingState &other):
 282         info(other.info),
 283         track(other.track),
 284         path(other.path),
 285         occupied_tracks(other.occupied_tracks),
 286         offset(other.offset),
 287         back_offset(other.back_offset),
 288         state(other.state),
 289         delay(other.delay),
 290         waypoint(other.waypoint),
 291         distance_traveled(other.distance_traveled),
 292         remaining_estimate(other.remaining_estimate),
 293         wait_time(other.wait_time),
 294         blocked_by(other.blocked_by)
 295 {
 296         ++occupied_tracks->refcount;
 297 }
 298
 299 TrainRoutePlanner::TrainRoutingState::~TrainRoutingState()
 300 {
 301         if(occupied_tracks && !--occupied_tracks->refcount)
 302                 delete occupied_tracks;
 303 }
 304
 305 Time::TimeDelta TrainRoutePlanner::TrainRoutingState::get_time_to_next_track() const
 306 {
 307         return ((track->get_type().get_path_length(path)-offset)/info->speed)*Time::sec+delay;
 308 }
 309
 310 bool TrainRoutePlanner::TrainRoutingState::is_occupying(Track &trk) const
 311 {
 312         OccupiedTrack *occ = occupied_tracks;
 313         for(unsigned n=occ->n_tracks; n>0; --n, occ=occ->next)
 314                 if(occ->track==&trk)
 315                         return true;
 316         return false;
 317 }
 318
 319 bool TrainRoutePlanner::TrainRoutingState::check_arrival()
 320 {
 321         TrainRouter &router = *info->router;
 322         TrackIter next_track = track.next(path);
 323
 324         if(waypoint<0 && router.is_destination(*track) && !router.is_destination(*next_track))
 325         {
 326                 state = ARRIVED;
 327                 return true;
 328         }
 329         else if(waypoint>=0 && router.is_waypoint(waypoint, *track) && !router.is_waypoint(waypoint, *next_track))
 330         {
 331                 ++waypoint;
 332                 if(waypoint>=static_cast<int>(router.get_n_waypoints()))
 333                         waypoint = -1;
 334         }
 335
 336         return false;
 337 }
 338
 339 void TrainRoutePlanner::TrainRoutingState::advance(float distance)
 340 {
 341         offset += distance;
 342         back_offset += distance;
 343
 344         OccupiedTrack *last_occ = occupied_tracks;
 345         for(unsigned n=occupied_tracks->n_tracks; n>1; --n)
 346                 last_occ = last_occ->next;
 347
 348         // XXX What if there's multiple tracks to remove?
 349         if(back_offset>last_occ->path_length)
 350         {
 351                 back_offset -= last_occ->path_length;
 352                 if(occupied_tracks->refcount>1)
 353                 {
 354                         --occupied_tracks->refcount;
 355                         occupied_tracks = new OccupiedTrack(*occupied_tracks);
 356                 }
 357                 --occupied_tracks->n_tracks;
 358         }
 359
 360         distance_traveled += distance;
 361         remaining_estimate -= distance;
 362 }
 363
 364 void TrainRoutePlanner::TrainRoutingState::advance(const Time::TimeDelta &dt)
 365 {
 366         if(delay>=dt)
 367         {
 368                 delay -= dt;
 369                 return;
 370         }
 371
 372         float secs = dt/Time::sec;
 373         if(delay)
 374         {
 375                 secs -= delay/Time::sec;
 376                 delay = Time::zero;
 377         }
 378
 379         if(state==MOVING)
 380                 advance(info->speed*secs);
 381         else if(state!=ARRIVED)
 382                 wait_time += secs*Time::sec;
 383 }
 384
 385 void TrainRoutePlanner::TrainRoutingState::advance_track(unsigned next_path)
 386 {
 387         float distance = occupied_tracks->path_length-offset;
 388         track = track.next(path);
 389         path = next_path;
 390         occupied_tracks = new OccupiedTrack(*track, path, occupied_tracks);
 391         advance(distance);
 392         offset = 0;
 393 }
 394
 395 void TrainRoutePlanner::TrainRoutingState::update_estimate()
 396 {
 397         TrackIter iter = track.reverse(path);
 398         float distance = info->router->get_metric(waypoint).get_distance_from(*iter.track(), iter.entry());
 399         distance += track->get_type().get_path_length(path)-offset;
 400         remaining_estimate = distance;
 401 }
 402
 403
 404 TrainRoutePlanner::RoutingStep::RoutingStep():
 405         prev(0)
 406 { }
 407
 408 TrainRoutePlanner::RoutingStep::RoutingStep(const RoutingStep *p):
 409         time(p->time),
 410         cost_estimate(p->cost_estimate),
 411         trains(p->trains),
 412         prev(p)
 413 { }
 414
 415 void TrainRoutePlanner::RoutingStep::create_successors(list<RoutingStep> &new_steps) const
 416 {
 417         RoutingStep next(this);
 418         if(next.update_states())
 419         {
 420                 if(next.check_deadlocks())
 421                         return;
 422
 423                 new_steps.push_back(next);
 424                 return;
 425         }
 426
 427         int train_index = find_next_train();
 428         if(train_index<0)
 429                 return;
 430
 431         TrainRoutingState &train = next.trains[train_index];
 432
 433         Time::TimeDelta dt = train.get_time_to_next_track();
 434         next.advance(dt);
 435
 436         if(train.check_arrival())
 437         {
 438                 new_steps.push_back(next);
 439                 return;
 440         }
 441
 442         TrackIter next_track = train.track.next(train.path);
 443         train.advance_track(0);
 444
 445         const TrackType::Endpoint &next_entry_ep = next_track.endpoint();
 446         for(unsigned i=0; next_entry_ep.paths>>i; ++i)
 447                 if(next_entry_ep.has_path(i))
 448                 {
 449                         train.path = i;
 450                         train.update_estimate();
 451                         next.update_estimate();
 452                         if(next.is_viable())
 453                                 new_steps.push_back(next);
 454                 }
 455
 456         if(next_entry_ep.paths!=next_track->get_type().get_paths())
 457         {
 458                 RoutingStep wait(this);
 459                 wait.advance(dt);
 460                 wait.trains[train_index].state = WAITING;
 461                 if(wait.is_viable())
 462                         new_steps.push_back(wait);
 463         }
 464 }
 465
 466 bool TrainRoutePlanner::RoutingStep::update_states()
 467 {
 468         bool changes = false;
 469         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 470         {
 471                 if(i->state==ARRIVED)
 472                         continue;
 473
 474                 TrainState old_state = i->state;
 475
 476                 TrackIter next_track = i->track.next(i->path);
 477                 if(next_track)
 478                 {
 479                         i->blocked_by = get_occupant(*next_track);
 480                         if(i->blocked_by>=0)
 481                                 i->state = BLOCKED;
 482                         else if(i->state==BLOCKED)
 483                                 i->state = MOVING;
 484                 }
 485                 else
 486                         i->state = BLOCKED;
 487
 488                 if(i->state!=old_state)
 489                         changes = true;
 490         }
 491
 492         return changes;
 493 }
 494
 495 bool TrainRoutePlanner::RoutingStep::check_deadlocks() const
 496 {
 497         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 498         {
 499                 if(i->state!=BLOCKED)
 500                         continue;
 501
 502                 if(i->blocked_by<0)
 503                         return true;
 504
 505                 int slow = i->blocked_by;
 506                 int fast = trains[slow].blocked_by;
 507                 while(fast>=0 && trains[fast].blocked_by>=0)
 508                 {
 509                         if(fast==slow)
 510                                 return true;
 511
 512                         slow = trains[slow].blocked_by;
 513                         fast = trains[trains[fast].blocked_by].blocked_by;
 514                 }
 515         }
 516
 517         return false;
 518 }
 519
 520 int TrainRoutePlanner::RoutingStep::get_occupant(Track &track) const
 521 {
 522         for(unsigned i=0; i<trains.size(); ++i)
 523                 if(trains[i].is_occupying(track))
 524                         return i;
 525
 526         return -1;
 527 }
 528
 529 int TrainRoutePlanner::RoutingStep::find_next_train() const
 530 {
 531         Time::TimeDelta min_dt;
 532         int next_train = -1;
 533         for(unsigned i=0; i<trains.size(); ++i)
 534                 if(trains[i].state==MOVING)
 535                 {
 536                         Time::TimeDelta dt = trains[i].get_time_to_next_track();
 537                         if(dt<min_dt || next_train<0)
 538                         {
 539                                 min_dt = dt;
 540                                 next_train = i;
 541                         }
 542                 }
 543
 544         return next_train;
 545 }
 546
 547 void TrainRoutePlanner::RoutingStep::advance(const Time::TimeDelta &dt)
 548 {
 549         time += dt;
 550         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 551                 i->advance(dt);
 552 }
 553
 554 void TrainRoutePlanner::RoutingStep::update_estimate()
 555 {
 556         cost_estimate = Time::zero;
 557         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 558                 if(i->remaining_estimate>=0)
 559                         cost_estimate += i->wait_time+((i->distance_traveled+i->remaining_estimate)/i->info->speed)*Time::sec;
 560 }
 561
 562 bool TrainRoutePlanner::RoutingStep::is_viable() const
 563 {
 564         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 565                 if(i->remaining_estimate<0)
 566                         return false;
 567
 568         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 569                 if(i->state==MOVING)
 570                         return true;
 571
 572         return false;
 573 }
 574
 575 bool TrainRoutePlanner::RoutingStep::is_goal() const
 576 {
 577         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 578                 if(i->state!=ARRIVED)
 579                         return false;
 580         return true;
 581 }
 582
 583 bool TrainRoutePlanner::RoutingStep::operator<(const RoutingStep &other) const
 584 {
 585         return cost_estimate<other.cost_estimate;
 586 }
 587
 588
 589 TrainRoutePlanner::PlanningThread::PlanningThread(TrainRoutePlanner &p):
 590         planner(p)
 591 {
 592         launch();
 593 }
 594
 595 void TrainRoutePlanner::PlanningThread::main()
 596 {
 597         planner.create_plan();
 598 }
 599
 600 } // namespace R2C2