source/libr2c2/trainrouteplanner.cpp

   1 #include "catalogue.h"
   2 #include "layout.h"
   3 #include "route.h"
   4 #include "train.h"
   5 #include "trainrouteplanner.h"
   6 #include "trainrouter.h"
   7 #include "vehicle.h"
   8
   9 using namespace std;
  10 using namespace Msp;
  11
  12 namespace R2C2 {
  13
  14 TrainRoutePlanner::TrainRoutePlanner(Layout &layout)
  15 {
  16         const map<unsigned, Train *> &trains = layout.get_trains();
  17         for(map<unsigned, Train *>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
  18         {
  19                 TrainRoutingInfo info(*i->second);
  20                 if(info.router && info.router->get_destination())
  21                         routed_trains.push_back(info);
  22         }
  23
  24         steps.push_back(RoutingStep());
  25         RoutingStep &start = steps.back();
  26         for(vector<TrainRoutingInfo>::iterator i=routed_trains.begin(); i!=routed_trains.end(); ++i)
  27                 start.trains.push_back(TrainRoutingState(*i));
  28 }
  29
  30 void TrainRoutePlanner::plan()
  31 {
  32         const RoutingStep *goal = 0;
  33         for(list<RoutingStep>::iterator i=steps.begin(); i!=steps.end(); ++i)
  34         {
  35                 if(i->is_goal())
  36                 {
  37                         goal = &*i;
  38                         break;
  39                 }
  40
  41                 add_steps(*i);
  42         }
  43
  44         if(goal)
  45                 create_routes(*goal);
  46 }
  47
  48 void TrainRoutePlanner::add_steps(const RoutingStep &step)
  49 {
  50         list<RoutingStep> new_steps;
  51         step.create_successors(new_steps);
  52         new_steps.sort();
  53         steps.merge(new_steps);
  54 }
  55
  56 void TrainRoutePlanner::create_routes(const RoutingStep &goal)
  57 {
  58         for(vector<TrainRoutingInfo>::iterator i=routed_trains.begin(); i!=routed_trains.end(); ++i)
  59         {
  60                 i->route = new Route(i->train->get_layout());
  61                 i->route->set_name("Router");
  62                 i->route->set_temporary(true);
  63         }
  64
  65         for(const RoutingStep *i=&goal; i; i=i->prev)
  66         {
  67                 for(vector<TrainRoutingState>::const_iterator j=i->trains.begin(); j!=i->trains.end(); ++j)
  68                 {
  69                         if(j->state==WAITING || j->state==BLOCKED)
  70                                 j->info->waits.push_front(&*j);
  71                         j->info->route->add_track(*j->track);
  72                 }
  73         }
  74
  75         for(vector<TrainRoutingInfo>::iterator i=routed_trains.begin(); i!=routed_trains.end(); ++i)
  76         {
  77                 i->router->set_route(i->route);
  78                 const TrainRoutingState *current_wait = 0;
  79                 for(list<const TrainRoutingState *>::const_iterator j=i->waits.begin(); j!=i->waits.end(); ++j)
  80                         if(!current_wait || (*j)->track.track()!=current_wait->track.track())
  81                         {
  82                                 Block &block = (*j)->track.next()->get_block();
  83                                 i->router->add_wait(block, 0);
  84                                 current_wait = *j;
  85                         }
  86         }
  87 }
  88
  89
  90 TrainRoutePlanner::TrainRoutingInfo::TrainRoutingInfo(Train &t):
  91         train(&t),
  92         speed(train->get_maximum_speed()),
  93         router(train->get_ai_of_type<TrainRouter>()),
  94         route(0)
  95 {
  96         // If no maximum speed is specified, use a sensible default
  97         if(!speed)
  98                 speed = 20*train->get_layout().get_catalogue().get_scale();
  99 }
 100
 101
 102 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(Track &t, unsigned p, OccupiedTrack *n):
 103         track(&t),
 104         path_length(track->get_type().get_path_length(p)),
 105         next(n),
 106         n_tracks(next ? next->n_tracks+1 : 1),
 107         refcount(1)
 108 {
 109         if(next)
 110                 ++next->refcount;
 111 }
 112
 113 TrainRoutePlanner::OccupiedTrack::OccupiedTrack(const OccupiedTrack &other):
 114         track(other.track),
 115         path_length(other.path_length),
 116         next(other.next),
 117         n_tracks(other.n_tracks),
 118         refcount(1)
 119 {
 120         if(next)
 121                 ++next->refcount;
 122 }
 123
 124 TrainRoutePlanner::OccupiedTrack::~OccupiedTrack()
 125 {
 126         if(next && !--next->refcount)
 127                 delete next;
 128 }
 129
 130
 131 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(TrainRoutingInfo &inf):
 132         info(&inf),
 133         occupied_tracks(0),
 134         state(MOVING),
 135         delay(info->router->get_departure_delay()),
 136         waypoint(info->router->get_n_waypoints() ? 0 : -1),
 137         blocked_by(-1)
 138 {
 139         const Vehicle *veh = &info->train->get_vehicle(0);
 140         // TODO margins
 141         TrackOffsetIter track_and_offs = veh->get_placement().get_position(VehiclePlacement::FRONT_BUFFER);
 142         track = track_and_offs.track_iter();
 143         offset = track_and_offs.offset();
 144         path = track->get_active_path();
 145
 146         while(Vehicle *next = veh->get_link(1))
 147                 veh = next;
 148         track_and_offs = veh->get_placement().get_position(VehiclePlacement::BACK_BUFFER);
 149         back_offset = track_and_offs.offset();
 150
 151         TrackIter iter = track_and_offs.track_iter();
 152         while(1)
 153         {
 154                 occupied_tracks = new OccupiedTrack(*iter, iter->get_active_path(), occupied_tracks);
 155                 if(iter.track()==track.track())
 156                         break;
 157                 iter = iter.next();
 158         }
 159 }
 160
 161 TrainRoutePlanner::TrainRoutingState::TrainRoutingState(const TrainRoutingState &other):
 162         info(other.info),
 163         track(other.track),
 164         path(other.path),
 165         occupied_tracks(other.occupied_tracks),
 166         offset(other.offset),
 167         back_offset(other.back_offset),
 168         state(other.state),
 169         delay(other.delay),
 170         waypoint(other.waypoint),
 171         blocked_by(other.blocked_by)
 172 {
 173         ++occupied_tracks->refcount;
 174 }
 175
 176 TrainRoutePlanner::TrainRoutingState::~TrainRoutingState()
 177 {
 178         if(!--occupied_tracks->refcount)
 179                 delete occupied_tracks;
 180 }
 181
 182 Time::TimeDelta TrainRoutePlanner::TrainRoutingState::get_time_to_next_track() const
 183 {
 184         return ((track->get_type().get_path_length(path)-offset)/info->speed)*Time::sec+delay;
 185 }
 186
 187 bool TrainRoutePlanner::TrainRoutingState::is_occupied(Track &trk) const
 188 {
 189         OccupiedTrack *occ = occupied_tracks;
 190         for(unsigned n=occ->n_tracks; n>0; --n, occ=occ->next)
 191                 if(occ->track==&trk)
 192                         return true;
 193         return false;
 194 }
 195
 196 bool TrainRoutePlanner::TrainRoutingState::check_arrival()
 197 {
 198         TrainRouter &router = *info->router;
 199         TrackIter next_track = track.next(path);
 200
 201         if(waypoint<0 && router.is_destination(*track) && !router.is_destination(*next_track))
 202         {
 203                 state = ARRIVED;
 204                 return true;
 205         }
 206         else if(waypoint>=0 && router.is_waypoint(waypoint, *track) && !router.is_waypoint(waypoint, *next_track))
 207         {
 208                 ++waypoint;
 209                 if(waypoint>=static_cast<int>(router.get_n_waypoints()))
 210                         waypoint = -1;
 211         }
 212
 213         return false;
 214 }
 215
 216 void TrainRoutePlanner::TrainRoutingState::advance(float distance)
 217 {
 218         offset += distance;
 219         back_offset += distance;
 220
 221         OccupiedTrack *last_occ = occupied_tracks;
 222         for(unsigned n=occupied_tracks->n_tracks; n>1; --n)
 223                 last_occ = last_occ->next;
 224
 225         // XXX What if there's multiple tracks to remove?
 226         if(back_offset>last_occ->path_length)
 227         {
 228                 back_offset -= last_occ->path_length;
 229                 if(occupied_tracks->refcount>1)
 230                 {
 231                         --occupied_tracks->refcount;
 232                         occupied_tracks = new OccupiedTrack(*occupied_tracks);
 233                 }
 234                 --occupied_tracks->n_tracks;
 235         }
 236 }
 237
 238 void TrainRoutePlanner::TrainRoutingState::advance_track(unsigned next_path)
 239 {
 240         float distance = occupied_tracks->path_length-offset;
 241         track = track.next(path);
 242         path = next_path;
 243         occupied_tracks = new OccupiedTrack(*track, path, occupied_tracks);
 244         advance(distance);
 245         offset = 0;
 246 }
 247
 248
 249 TrainRoutePlanner::RoutingStep::RoutingStep():
 250         prev(0)
 251 { }
 252
 253 TrainRoutePlanner::RoutingStep::RoutingStep(const RoutingStep *p):
 254         time(p->time),
 255         trains(p->trains),
 256         prev(p)
 257 { }
 258
 259 void TrainRoutePlanner::RoutingStep::create_successors(list<RoutingStep> &new_steps) const
 260 {
 261         RoutingStep next(this);
 262         if(next.update_states())
 263         {
 264                 if(next.check_deadlocks())
 265                         return;
 266
 267                 new_steps.push_back(next);
 268                 return;
 269         }
 270
 271         int train_index = find_next_train();
 272         if(train_index<0)
 273                 return;
 274
 275         TrainRoutingState &train = next.trains[train_index];
 276
 277         Time::TimeDelta dt = train.get_time_to_next_track();
 278         next.advance(dt);
 279
 280         if(train.check_arrival())
 281         {
 282                 new_steps.push_back(next);
 283                 return;
 284         }
 285
 286         TrackIter next_track = train.track.next(train.path);
 287         train.advance_track(0);
 288
 289         const TrackType::Endpoint &next_entry_ep = next_track.endpoint();
 290         for(unsigned i=0; next_entry_ep.paths>>i; ++i)
 291                 if(next_entry_ep.has_path(i))
 292                 {
 293                         train.path = i;
 294                         if(next.is_viable())
 295                                 new_steps.push_back(next);
 296                 }
 297
 298         if(next_entry_ep.paths!=next_track->get_type().get_paths())
 299         {
 300                 RoutingStep wait(this);
 301                 wait.advance(dt);
 302                 wait.trains[train_index].state = WAITING;
 303                 if(wait.is_viable())
 304                         new_steps.push_back(wait);
 305         }
 306 }
 307
 308 bool TrainRoutePlanner::RoutingStep::update_states()
 309 {
 310         bool changes = false;
 311         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 312         {
 313                 if(i->state==ARRIVED)
 314                         continue;
 315
 316                 TrainState old_state = i->state;
 317
 318                 TrackIter next_track = i->track.next(i->path);
 319                 if(next_track)
 320                 {
 321                         i->blocked_by = get_occupant(*next_track);
 322                         if(i->blocked_by>=0)
 323                                 i->state = BLOCKED;
 324                         else if(i->state==BLOCKED)
 325                                 i->state = MOVING;
 326                 }
 327                 else
 328                         i->state = BLOCKED;
 329
 330                 if(i->state!=old_state)
 331                         changes = true;
 332         }
 333
 334         return changes;
 335 }
 336
 337 bool TrainRoutePlanner::RoutingStep::check_deadlocks() const
 338 {
 339         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 340         {
 341                 if(i->state!=BLOCKED)
 342                         continue;
 343
 344                 if(i->blocked_by<0)
 345                         return true;
 346
 347                 int slow = i->blocked_by;
 348                 int fast = trains[slow].blocked_by;
 349                 while(fast>=0 && trains[fast].blocked_by>=0)
 350                 {
 351                         if(fast==slow)
 352                                 return true;
 353
 354                         slow = trains[slow].blocked_by;
 355                         fast = trains[trains[fast].blocked_by].blocked_by;
 356                 }
 357         }
 358
 359         return false;
 360 }
 361
 362 int TrainRoutePlanner::RoutingStep::get_occupant(Track &track) const
 363 {
 364         for(unsigned i=0; i<trains.size(); ++i)
 365                 if(trains[i].is_occupied(track))
 366                         return i;
 367
 368         return -1;
 369 }
 370
 371 int TrainRoutePlanner::RoutingStep::find_next_train() const
 372 {
 373         Time::TimeDelta min_dt;
 374         int next_train = -1;
 375         for(unsigned i=0; i<trains.size(); ++i)
 376                 if(trains[i].state==MOVING)
 377                 {
 378                         Time::TimeDelta dt = trains[i].get_time_to_next_track();
 379                         if(dt<min_dt || next_train<0)
 380                         {
 381                                 min_dt = dt;
 382                                 next_train = i;
 383                         }
 384                 }
 385
 386         return next_train;
 387 }
 388
 389 void TrainRoutePlanner::RoutingStep::advance(const Time::TimeDelta &dt)
 390 {
 391         time += dt;
 392         for(vector<TrainRoutingState>::iterator i=trains.begin(); i!=trains.end(); ++i)
 393         {
 394                 if(i->delay)
 395                 {
 396                         i->delay -= dt;
 397                         if(i->delay>Time::zero)
 398                                 continue;
 399                         i->delay = Time::zero;
 400                 }
 401                 else if(i->state==MOVING)
 402                         i->advance(i->info->speed*(dt/Time::sec));
 403         }
 404 }
 405
 406 bool TrainRoutePlanner::RoutingStep::is_viable() const
 407 {
 408         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 409                 if(i->state==MOVING)
 410                         return true;
 411
 412         return false;
 413 }
 414
 415 bool TrainRoutePlanner::RoutingStep::is_goal() const
 416 {
 417         for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
 418                 if(i->state!=ARRIVED)
 419                         return false;
 420         return true;
 421 }
 422
 423 bool TrainRoutePlanner::RoutingStep::operator<(const RoutingStep &other) const
 424 {
 425         return time<other.time;
 426 }
 427
 428 } // namespace R2C2