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