source/libr2c2/route.cpp

   1 #include <queue>
   2 #include <msp/core/maputils.h>
   3 #include <msp/strings/format.h>
   4 #include <msp/strings/utils.h>
   5 #include "layout.h"
   6 #include "route.h"
   7 #include "track.h"
   8 #include "trackiter.h"
   9 #include "tracktype.h"
  10 #include "zone.h"
  11
  12 using namespace std;
  13 using namespace Msp;
  14
  15 namespace {
  16
  17 using namespace R2C2;
  18
  19 typedef std::pair<Track *, unsigned> Key;
  20
  21 struct Node
  22 {
  23         TrackIter track;
  24         Node *prev;
  25         float dist;
  26
  27         Node():
  28                 prev(0), dist(0)
  29         { }
  30
  31         Node(const TrackIter &t):
  32                 track(t), prev(0), dist(0)
  33         { }
  34
  35         Node(const TrackIter &t, Node &r, float d):
  36                 track(t), prev(&r), dist(prev->dist+d)
  37         { }
  38
  39         bool operator<(const Node &other) const
  40         { return dist>other.dist; }
  41 };
  42
  43 struct TrackMatch
  44 {
  45         Track &track;
  46
  47         TrackMatch(Track &t): track(t) { }
  48
  49         bool operator()(Track &t) const { return &t==&track; }
  50 };
  51
  52 struct TrackInSet
  53 {
  54         const set<Track *> &tracks;
  55
  56         TrackInSet(const set<Track *> &t): tracks(t) { }
  57
  58         bool operator()(Track &t) const { return tracks.count(&t); }
  59 };
  60
  61 template<typename Pred>
  62 list<Track *> dijkstra(const TrackIter &from, const Pred &goal)
  63 {
  64         map<Key, Node> track_nodes;
  65         priority_queue<Node> nodes;
  66         Node *final = 0;
  67
  68         nodes.push(from);
  69
  70         while(!nodes.empty())
  71         {
  72                 Node lowest = nodes.top();
  73                 nodes.pop();
  74
  75                 Key key(lowest.track.track(), lowest.track.entry());
  76                 if(track_nodes.count(key))
  77                         continue;
  78
  79                 Node &ref = track_nodes[key] = lowest;
  80                 if(goal(*lowest.track))
  81                 {
  82                         final = &ref;
  83                         break;
  84                 }
  85
  86                 const TrackType::Endpoint &ep = lowest.track.endpoint();
  87                 for(unsigned i=0; ep.paths>>i; ++i)
  88                         if(ep.has_path(i))
  89                         {
  90                                 TrackIter next = lowest.track.next(i);
  91                                 if(!next)
  92                                         continue;
  93
  94                                 if(track_nodes.count(Key(next.track(), next.entry())))
  95                                         continue;
  96
  97                                 nodes.push(Node(next, ref, lowest.track->get_type().get_path_length(i)));
  98                         }
  99         }
 100
 101         list<Track *> result;
 102         for(Node *node=final; node; node=node->prev)
 103                 result.push_front(&*node->track);
 104
 105         return result;
 106 }
 107
 108 template<typename Pred>
 109 Route *create_route(const TrackIter &from, const Pred &goal)
 110 {
 111         list<Track *> tracks = dijkstra(from, goal);
 112
 113         if(tracks.empty())
 114                 return 0;
 115
 116         Route *route = new Route(from->get_layout());
 117         for(list<Track *>::iterator i=tracks.begin(); i!=tracks.end(); ++i)
 118                 route->add_track(**i);
 119
 120         route->set_name("Pathfinder");
 121         route->set_temporary(true);
 122
 123         return route;
 124 }
 125
 126 }
 127
 128
 129 namespace R2C2 {
 130
 131 Route::Route(Layout &l):
 132         TrackChain(l),
 133         temporary(false)
 134 {
 135         layout.add(*this);
 136 }
 137
 138 Route::~Route()
 139 {
 140         layout.remove(*this);
 141 }
 142
 143 void Route::set_name(const string &n)
 144 {
 145         name = n;
 146         signal_name_changed.emit(name);
 147 }
 148
 149 void Route::set_temporary(bool t)
 150 {
 151         temporary = t;
 152 }
 153
 154 void Route::set_turnout(unsigned addr, unsigned path)
 155 {
 156         if(!addr)
 157                 throw invalid_argument("Route::set_turnout");
 158         int &state = get_item(turnouts, addr);
 159         if(state>=0 && path!=static_cast<unsigned>(state))
 160                 throw logic_error("route conflict");
 161         state = path;
 162 }
 163
 164 void Route::update_turnouts()
 165 {
 166         set<unsigned> found;
 167         for(set<Track *>::const_iterator i=tracks.begin(); i!=tracks.end(); ++i)
 168                 if(unsigned tid = (*i)->get_turnout_id())
 169                 {
 170                         found.insert(tid);
 171
 172                         const vector<TrackType::Endpoint> &endpoints = (*i)->get_type().get_endpoints();
 173                         const vector<Track *> &links = (*i)->get_links();
 174
 175                         // Build a combined path mask from linked endpoints
 176                         unsigned mask = (*i)->get_type().get_paths();
 177                         for(unsigned j=0; j<endpoints.size(); ++j)
 178                         {
 179                                 if(!tracks.count(links[j]))
 180                                         continue;
 181
 182                                 if(unsigned tid2 = links[j]->get_turnout_id())
 183                                 {
 184                                         const TrackType::Endpoint &ep = links[j]->get_type().get_endpoint(links[j]->get_link_slot(**i));
 185                                         int p = get_turnout(tid2);
 186                                         if(p>=0 && !ep.has_path(p))
 187                                         {
 188                                                 // The linked track is a turnout and has a path which is incompatible with this endpoint
 189                                                 mask &= ~endpoints[j].paths;
 190                                                 continue;
 191                                         }
 192                                 }
 193                                 mask &= endpoints[j].paths;
 194                         }
 195
 196                         if(mask && !(mask&(mask-1)))
 197                         {
 198                                 // Exactly one possible choice, set the path accordingly
 199                                 unsigned path = 0;
 200                                 for(; (mask && !(mask&1)); mask>>=1, ++path) ;
 201                                 turnouts[tid] = path;
 202                         }
 203                         else if(!turnouts.count(tid))
 204                                 // More than one possible choice, and no existing entry - set as undecided
 205                                 turnouts[tid] = -1;
 206                 }
 207
 208         // Remove any turnouts that do not exist in the route
 209         for(map<unsigned, int>::iterator i=turnouts.begin(); i!=turnouts.end();)
 210         {
 211                 if(!found.count(i->first))
 212                         turnouts.erase(i++);
 213                 else
 214                         ++i;
 215         }
 216 }
 217
 218 int Route::get_turnout(unsigned id) const
 219 {
 220         map<unsigned, int>::const_iterator i = turnouts.find(id);
 221         if(i!=turnouts.end())
 222                 return i->second;
 223         return -1;
 224 }
 225
 226 unsigned Route::get_path(Track &trk) const
 227 {
 228         if(unsigned tid = trk.get_turnout_id())
 229         {
 230                 map<unsigned, int>::const_iterator i = turnouts.find(tid);
 231                 if(i!=turnouts.end())
 232                         return i->second;
 233         }
 234         return trk.get_active_path();
 235 }
 236
 237 void Route::add_track_chain(const TrackIter &start, const TurnoutMap &trnts)
 238 {
 239         if(!start)
 240                 throw invalid_argument("Route::add_track_chain");
 241
 242         TrackIter iter = start;
 243         while(iter)
 244         {
 245                 if(iter->get_type().is_dead_end())
 246                         break;
 247
 248                 if(has_track(*iter))
 249                         break;
 250
 251                 int path = 0;
 252                 if(iter->get_turnout_id())
 253                 {
 254                         TurnoutMap::const_iterator i = trnts.find(iter->get_turnout_id());
 255                         if(i==trnts.end())
 256                                 break;
 257
 258                         path = i->second;
 259                 }
 260
 261                 add_track(*iter);
 262
 263                 iter = iter.next(path);
 264         }
 265 }
 266
 267 void Route::on_track_added(Track &)
 268 {
 269         update_turnouts();
 270 }
 271
 272 void Route::save(list<DataFile::Statement> &st) const
 273 {
 274         st.push_back((DataFile::Statement("name"), name));
 275         for(map<unsigned, int>::const_iterator i=turnouts.begin(); i!=turnouts.end(); ++i)
 276                 st.push_back((DataFile::Statement("turnout"), i->first, i->second));
 277 }
 278
 279 Route *Route::find(const TrackIter &from, Track &to)
 280 {
 281         return create_route(from, TrackMatch(to));
 282 }
 283
 284 Route *Route::find(const TrackIter &from, const Route &to)
 285 {
 286         return create_route(from, TrackInSet(to.get_tracks()));
 287 }
 288
 289 Route *Route::find(const TrackIter &from, const Zone &to)
 290 {
 291         return create_route(from, TrackInSet(to.get_tracks()));
 292 }
 293
 294 Route *Route::find(const TrackIter &from, const set<Track *> &to)
 295 {
 296         return create_route(from, TrackInSet(to));
 297 }
 298
 299
 300 Route::Loader::Loader(Route &r):
 301         DataFile::ObjectLoader<Route>(r)
 302 {
 303         add("name",    &Route::name);
 304         add("turnout", &Loader::turnout);
 305 }
 306
 307 void Route::Loader::finish()
 308 {
 309         const set<Track *> &ltracks = obj.layout.get_all<Track>();
 310         for(set<Track *>::const_iterator i=ltracks.begin(); i!=ltracks.end(); ++i)
 311         {
 312                 unsigned tid = (*i)->get_turnout_id();
 313                 if(!tid)
 314                         continue;
 315
 316                 TurnoutMap::iterator j = turnouts.find(tid);
 317                 if(j==turnouts.end())
 318                         continue;
 319
 320                 const vector<TrackType::Endpoint> &eps = (*i)->get_type().get_endpoints();
 321                 for(unsigned k=0; k<eps.size(); ++k)
 322                         if(eps[k].has_path(j->second))
 323                         {
 324                                 Track *link = (*i)->get_link(k);
 325                                 if(!obj.tracks.count(link))
 326                                         obj.add_track_chain(TrackIter(link, link->get_link_slot(**i)), turnouts);
 327                                 if(!obj.tracks.count(*i))
 328                                         obj.add_track_chain(TrackIter(*i, k), turnouts);
 329                                 break;
 330                         }
 331
 332                 break;
 333         }
 334 }
 335
 336 void Route::Loader::turnout(unsigned id, unsigned path)
 337 {
 338         turnouts[id] = path;
 339 }
 340
 341 } // namespace R2C2