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_temporary(bool t)
 144 {
 145         temporary = t;
 146 }
 147
 148 void Route::update_turnouts()
 149 {
 150         set<unsigned> found;
 151         for(set<Track *>::const_iterator i=tracks.begin(); i!=tracks.end(); ++i)
 152                 if((*i)->get_type().is_turnout())
 153                 {
 154                         found.insert((*i)->get_turnout_address());
 155                         update_turnout(**i);
 156                 }
 157
 158         // Remove any turnouts that do not exist in the route
 159         for(map<unsigned, int>::iterator i=turnouts.begin(); i!=turnouts.end();)
 160         {
 161                 if(!found.count(i->first))
 162                         turnouts.erase(i++);
 163                 else
 164                         ++i;
 165         }
 166 }
 167
 168 void Route::update_turnout(Track &track)
 169 {
 170         if(!track.get_type().is_turnout())
 171                 return;
 172
 173         // Build a combined path mask from linked endpoints
 174         unsigned nls = track.get_n_link_slots();
 175         unsigned mask = track.get_type().get_paths();
 176         for(unsigned i=0; i<nls; ++i)
 177         {
 178                 Track *link = track.get_link(i);
 179                 if(!tracks.count(link))
 180                         continue;
 181
 182                 unsigned ep_mask = track.get_type().get_endpoint(i).paths;
 183                 if(link->get_type().is_turnout())
 184                 {
 185                         const TrackType::Endpoint &link_ep = link->get_type().get_endpoint(link->get_link_slot(track));
 186                         int p = get_turnout(link->get_turnout_address());
 187                         if(p>=0 && !link_ep.has_path(p))
 188                                 // The linked track is a turnout and has a path which is incompatible with this endpoint
 189                                 ep_mask = ~ep_mask;
 190                 }
 191
 192                 mask &= ep_mask;
 193         }
 194
 195         unsigned taddr = track.get_turnout_address();
 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[taddr] = path;
 202         }
 203         else if(!turnouts.count(taddr))
 204                 // More than one possible choice, and no existing entry - set as undecided
 205                 turnouts[taddr] = -1;
 206 }
 207
 208 int Route::get_turnout(unsigned id) const
 209 {
 210         map<unsigned, int>::const_iterator i = turnouts.find(id);
 211         if(i!=turnouts.end())
 212                 return i->second;
 213         return -1;
 214 }
 215
 216 unsigned Route::get_path(Track &trk) const
 217 {
 218         if(trk.get_type().is_turnout())
 219         {
 220                 map<unsigned, int>::const_iterator i = turnouts.find(trk.get_turnout_address());
 221                 if(i!=turnouts.end())
 222                         return i->second;
 223         }
 224         return trk.get_active_path();
 225 }
 226
 227 void Route::add_turnout(Track &track, unsigned path)
 228 {
 229         TrackSet tracks_to_add;
 230         tracks_to_add.insert(&track);
 231         unsigned nls = track.get_n_link_slots();
 232         for(unsigned i=0; i<nls; ++i)
 233                 if(track.get_type().get_endpoint(i).has_path(path))
 234                 {
 235                         TrackIter iter = TrackIter(&track, i).flip();
 236                         for(; (iter && !iter->get_type().is_turnout()); iter=iter.next())
 237                                 tracks_to_add.insert(&*iter);
 238                 }
 239
 240         add_tracks(tracks_to_add);
 241 }
 242
 243 void Route::on_track_added(Track &track)
 244 {
 245         update_turnout(track);
 246         unsigned nls = track.get_n_link_slots();
 247         for(unsigned i=0; i<nls; ++i)
 248                 if(Track *link = track.get_link(i))
 249                         if(tracks.count(link))
 250                                 update_turnout(*link);
 251 }
 252
 253 void Route::save(list<DataFile::Statement> &st) const
 254 {
 255         st.push_back((DataFile::Statement("name"), name));
 256         for(map<unsigned, int>::const_iterator i=turnouts.begin(); i!=turnouts.end(); ++i)
 257                 st.push_back((DataFile::Statement("turnout"), i->first, i->second));
 258 }
 259
 260 DataFile::Statement Route::save_reference() const
 261 {
 262         return (DataFile::Statement("route"), name);
 263 }
 264
 265 Route *Route::find(const TrackIter &from, Track &to)
 266 {
 267         return create_route(from, TrackMatch(to));
 268 }
 269
 270 Route *Route::find(const TrackIter &from, const Route &to)
 271 {
 272         return create_route(from, TrackInSet(to.get_tracks()));
 273 }
 274
 275 Route *Route::find(const TrackIter &from, const Zone &to)
 276 {
 277         return create_route(from, TrackInSet(to.get_tracks()));
 278 }
 279
 280 Route *Route::find(const TrackIter &from, const set<Track *> &to)
 281 {
 282         return create_route(from, TrackInSet(to));
 283 }
 284
 285
 286 Route::Loader::Loader(Route &r):
 287         DataFile::ObjectLoader<Route>(r)
 288 {
 289         add("name",    &Loader::name);
 290         add("turnout", &Loader::turnout);
 291 }
 292
 293 void Route::Loader::finish()
 294 {
 295         const set<Track *> &ltracks = obj.layout.get_all<Track>();
 296         map<Track *, unsigned> turnout_tracks;
 297         for(set<Track *>::const_iterator i=ltracks.begin(); i!=ltracks.end(); ++i)
 298                 if((*i)->get_type().is_turnout())
 299                 {
 300                         TurnoutMap::iterator j = turnouts.find((*i)->get_turnout_address());
 301                         if(j!=turnouts.end())
 302                                 turnout_tracks[*i] = j->second;
 303                 }
 304
 305         for(map<Track *, unsigned>::iterator i=turnout_tracks.begin(); i!=turnout_tracks.end(); )
 306         {
 307                 if(obj.check_validity(*i->first)==VALID)
 308                 {
 309                         obj.add_turnout(*i->first, i->second);
 310                         turnout_tracks.erase(i);
 311                         i = turnout_tracks.begin();
 312                 }
 313                 else
 314                         ++i;
 315         }
 316 }
 317
 318 void Route::Loader::name(const string &n)
 319 {
 320         obj.name = n;
 321 }
 322
 323 void Route::Loader::turnout(unsigned id, unsigned path)
 324 {
 325         turnouts[id] = path;
 326 }
 327
 328 } // namespace R2C2