source/libmarklin/route.cpp

   1 /* $Id$
   2
   3 This file is part of the MSP Märklin suite
   4 Copyright © 2007-2010  Mikkosoft Productions, Mikko Rasa
   5 Distributed under the GPL
   6 */
   7
   8 #include <queue>
   9 #include <msp/strings/formatter.h>
  10 #include "layout.h"
  11 #include "route.h"
  12 #include "track.h"
  13 #include "tracktype.h"
  14
  15 using namespace std;
  16 using namespace Msp;
  17
  18 namespace {
  19
  20 using namespace Marklin;
  21
  22 typedef std::pair<const Track *, unsigned> Key;
  23
  24 struct Node
  25 {
  26         const Track *track;
  27         unsigned ep;
  28         Node *prev;
  29         float dist;
  30
  31         Node():
  32                 track(0), ep(0), prev(0), dist(0)
  33         { }
  34
  35         Node(const Track &t, unsigned e):
  36                 track(&t), ep(e), prev(0), dist(0)
  37         { }
  38
  39         Node(const Track &t, unsigned e, Node &r, float d):
  40                 track(&t), ep(e), prev(&r), dist(prev->dist+d)
  41         { }
  42
  43         bool operator<(const Node &other) const
  44         { return dist>other.dist; }
  45 };
  46
  47 struct TrackMatch
  48 {
  49         const Track &track;
  50
  51         TrackMatch(const Track &t): track(t) { }
  52
  53         bool operator()(const Track &t) const { return &t==&track; }
  54 };
  55
  56 struct TrackInSet
  57 {
  58         const set<const Track *> &tracks;
  59
  60         TrackInSet(const set<const Track *> &t): tracks(t) { }
  61
  62         bool operator()(const Track &t) const { return tracks.count(&t); }
  63 };
  64
  65 template<typename Pred>
  66 list<const Track *> dijkstra(const Track &from, unsigned ep, const Pred &goal)
  67 {
  68         map<Key, Node> track_nodes;
  69         priority_queue<Node> nodes;
  70         Node *final = 0;
  71
  72         nodes.push(Node(from, ep));
  73
  74         while(!nodes.empty())
  75         {
  76                 Node lowest = nodes.top();
  77                 nodes.pop();
  78
  79                 Key key(lowest.track, lowest.ep);
  80                 if(track_nodes.count(key))
  81                         continue;
  82
  83                 Node &ref = track_nodes[key] = lowest;
  84                 if(goal(*lowest.track))
  85                 {
  86                         final = &ref;
  87                         break;
  88                 }
  89
  90                 const TrackType &type = lowest.track->get_type();
  91                 const vector<Endpoint> &eps = type.get_endpoints();
  92                 const vector<Track *> &links = lowest.track->get_links();
  93                 for(unsigned i=0; i<eps.size(); ++i)
  94                 {
  95                         if(i==lowest.ep || !links[i])
  96                                 continue;
  97
  98                         unsigned link_ep = links[i]->get_endpoint_by_link(*lowest.track);
  99                         if(track_nodes.count(Key(links[i], link_ep)))
 100                                 continue;
 101
 102                         unsigned mask = eps[i].paths&eps[lowest.ep].paths;
 103                         if(!mask)
 104                                 continue;
 105
 106                         unsigned path=0;
 107                         for(; !(mask&1); ++path, mask>>=1) ;
 108                         nodes.push(Node(*links[i], links[i]->get_endpoint_by_link(*lowest.track), ref, type.get_path_length(path)));
 109                 }
 110         }
 111
 112         if(!final)
 113                 throw InvalidParameterValue("Could not find a route");
 114
 115         list<const Track *> result;
 116         for(Node *node=final; node; node=node->prev)
 117                 result.push_front(node->track);
 118
 119         return result;
 120 }
 121
 122 template<typename Pred>
 123 Route *create_route(const Track &from, unsigned ep, const Pred &goal)
 124 {
 125         list<const Track *> tracks = dijkstra(from, ep, goal);
 126
 127         Route *route = new Route(from.get_layout());
 128         for(list<const Track *>::iterator i=tracks.begin(); i!=tracks.end(); ++i)
 129                 route->add_track(**i);
 130
 131         route->set_name("Pathfinder");
 132         route->set_temporary(true);
 133
 134         return route;
 135 }
 136
 137 }
 138
 139
 140 namespace Marklin {
 141
 142 Route::Route(Layout &l):
 143         layout(l),
 144         temporary(false)
 145 {
 146         layout.add_route(*this);
 147         layout.signal_track_removed.connect(sigc::mem_fun(this, &Route::track_removed));
 148 }
 149
 150 Route::~Route()
 151 {
 152         layout.remove_route(*this);
 153 }
 154
 155 void Route::set_name(const string &n)
 156 {
 157         name = n;
 158         signal_name_changed.emit(name);
 159 }
 160
 161 void Route::set_temporary(bool t)
 162 {
 163         temporary = t;
 164 }
 165
 166 void Route::set_turnout(unsigned addr, unsigned path)
 167 {
 168         if(!addr)
 169                 throw InvalidParameterValue("Invalid turnout address");
 170         map<unsigned, int>::iterator i = turnouts.find(addr);
 171         if(i==turnouts.end())
 172                 throw KeyError("Turnout is not in this route");
 173         if(i->second>=0 && path!=static_cast<unsigned>(i->second))
 174                 throw InvalidState("Setting conflicts with route");
 175         i->second = path;
 176 }
 177
 178 void Route::update_turnouts()
 179 {
 180         set<unsigned> found;
 181         for(set<const Track *>::const_iterator i=tracks.begin(); i!=tracks.end(); ++i)
 182                 if(unsigned tid = (*i)->get_turnout_id())
 183                 {
 184                         found.insert(tid);
 185
 186                         const vector<Endpoint> &endpoints = (*i)->get_type().get_endpoints();
 187                         const vector<Track *> &links = (*i)->get_links();
 188
 189                         // Build a combined path mask from linked endpoints
 190                         unsigned mask = 15;
 191                         for(unsigned j=0; j<endpoints.size(); ++j)
 192                         {
 193                                 if(!tracks.count(links[j]))
 194                                         continue;
 195
 196                                 if(unsigned tid2 = links[j]->get_turnout_id())
 197                                 {
 198                                         const Endpoint &ep = links[j]->get_type().get_endpoints()[links[j]->get_endpoint_by_link(**i)];
 199                                         int p = get_turnout(tid2);
 200                                         if(p>=0 && !(ep.paths&(1<<p)))
 201                                         {
 202                                                 // The linked track is a turnout and has a path which is incompatible with this endpoint
 203                                                 mask &= ~endpoints[j].paths;
 204                                                 continue;
 205                                         }
 206                                 }
 207                                 mask &= endpoints[j].paths;
 208                         }
 209
 210                         if(mask && !(mask&(mask-1)))
 211                         {
 212                                 // Exactly one possible choice, set the path accordingly
 213                                 unsigned path = 0;
 214                                 for(; (mask && !(mask&1)); mask>>=1, ++path) ;
 215                                 turnouts[tid] = path;
 216                         }
 217                         else if(!turnouts.count(tid))
 218                                 // More than one possible choice, and no existing entry - set as undecided
 219                                 turnouts[tid] = -1;
 220                 }
 221
 222         // Remove any turnouts that do not exist in the route
 223         for(map<unsigned, int>::iterator i=turnouts.begin(); i!=turnouts.end();)
 224         {
 225                 if(!found.count(i->first))
 226                         turnouts.erase(i++);
 227                 else
 228                         ++i;
 229         }
 230 }
 231
 232 int Route::get_turnout(unsigned id) const
 233 {
 234         map<unsigned, int>::const_iterator i = turnouts.find(id);
 235         if(i!=turnouts.end())
 236                 return i->second;
 237         return -1;
 238 }
 239
 240 void Route::add_track(const Track &trk)
 241 {
 242         if(tracks.count(&trk))
 243                 return;
 244
 245         if(!tracks.empty())
 246         {
 247                 unsigned valid = check_validity(trk);
 248                 if(!(valid&1))
 249                         throw Exception("Not linked to existing tracks");
 250                 else if(!(valid&2))
 251                         throw Exception("Branching routes not allowed");
 252                 else if(!(valid&4))
 253                         throw Exception("Route must be smooth");
 254         }
 255
 256         tracks.insert(&trk);
 257         update_turnouts();
 258 }
 259
 260 void Route::add_tracks(const set<const Track *> &trks)
 261 {
 262         set<const Track *> pending;
 263         for(set<const Track *>::const_iterator i=trks.begin(); i!=trks.end(); ++i)
 264                 if(!tracks.count(*i))
 265                         pending.insert(*i);
 266
 267         while(!pending.empty())
 268         {
 269                 bool found = false;
 270                 for(set<const Track *>::const_iterator i=pending.begin(); i!=pending.end(); ++i)
 271                         if(tracks.empty() || check_validity(**i)==7)
 272                         {
 273                                 tracks.insert(*i);
 274                                 pending.erase(*i);
 275                                 found = true;
 276                                 break;
 277                         }
 278
 279                 if(!found)
 280                         throw Exception("Could not add all tracks to route");
 281         }
 282
 283         update_turnouts();
 284 }
 285
 286 void Route::add_track_chain(const Track &start, unsigned ep, const TurnoutMap &trnts)
 287 {
 288         const Track *track = &start;
 289         while(1)
 290         {
 291                 if(track->get_type().is_dead_end())
 292                         break;
 293
 294                 if(tracks.count(track))
 295                         break;
 296
 297                 int path = 0;
 298                 if(track->get_turnout_id())
 299                 {
 300                         TurnoutMap::const_iterator i = trnts.find(track->get_turnout_id());
 301                         if(i==trnts.end())
 302                                 break;
 303
 304                         path = i->second;
 305                 }
 306
 307                 add_track(*track);
 308
 309                 unsigned out_ep = track->traverse(ep, path);
 310                 Track *next = track->get_links()[out_ep];
 311                 if(!next)
 312                         break;
 313
 314                 ep = next->get_endpoint_by_link(*track);
 315                 track = next;
 316         }
 317 }
 318
 319 void Route::save(list<DataFile::Statement> &st) const
 320 {
 321         st.push_back((DataFile::Statement("name"), name));
 322         for(map<unsigned, int>::const_iterator i=turnouts.begin(); i!=turnouts.end(); ++i)
 323                 st.push_back((DataFile::Statement("turnout"), i->first, i->second));
 324 }
 325
 326 unsigned Route::check_validity(const Track &trk) const
 327 {
 328         unsigned result = 4;
 329         for(set<const Track *>::const_iterator i=tracks.begin(); i!=tracks.end(); ++i)
 330         {
 331                 int epi=(*i)->get_endpoint_by_link(trk);
 332                 if(epi>=0)
 333                 {
 334                         // Linked to an existing track - good
 335                         result |= 1;
 336                         const vector<Endpoint> &endpoints = (*i)->get_type().get_endpoints();
 337                         if(unsigned tid=(*i)->get_turnout_id())
 338                         {
 339                                 int r = get_turnout(tid);
 340                                 if(r>=0)
 341                                 {
 342                                         // Linking to a turnout with path set is only good if we're continuing that path
 343                                         if(endpoints[epi].paths&(1<<r))
 344                                                 result |= 2;
 345                                 }
 346                                 else
 347                                 {
 348                                         // Linked to a turnout with no path set - find out other linked tracks
 349                                         unsigned count = 0;
 350                                         const vector<Track *> &links = (*i)->get_links();
 351                                         int epj = -1;
 352                                         for(unsigned k=0; k<endpoints.size(); ++k)
 353                                                 if(tracks.count(links[k]))
 354                                                 {
 355                                                         ++count;
 356                                                         epj = k;
 357                                                 }
 358
 359                                         // Only good if at most one other track is linked to the turnout
 360                                         if(count<=1)
 361                                         {
 362                                                 result |= 2;
 363                                                 if(epj>=0 && !(endpoints[epi].paths&endpoints[epj].paths))
 364                                                         // Impossible path through the turnout - not good
 365                                                         result &= 3;
 366                                         }
 367                                 }
 368                         }
 369                         else
 370                                 // Linked to something linear - good
 371                                 result |= 2;
 372                 }
 373         }
 374
 375         return result;
 376 }
 377
 378 void Route::track_removed(Track &t)
 379 {
 380         tracks.erase(&t);
 381 }
 382
 383 Route *Route::find(const Track &from, unsigned ep, const Track &to)
 384 {
 385         return create_route(from, ep, TrackMatch(to));
 386 }
 387
 388 Route *Route::find(const Track &from, unsigned ep, const Route &to)
 389 {
 390         return create_route(from, ep, TrackInSet(to.get_tracks()));
 391 }
 392
 393 Route *Route::find(const Track &from, unsigned ep, const set<const Track *> &to)
 394 {
 395         return create_route(from, ep, TrackInSet(to));
 396 }
 397
 398
 399 Route::Loader::Loader(Route &r):
 400         DataFile::BasicLoader<Route>(r)
 401 {
 402         add("name",    &Route::name);
 403         add("turnout", &Loader::turnout);
 404 }
 405
 406 void Route::Loader::finish()
 407 {
 408         const set<Track *> &ltracks = obj.layout.get_tracks();
 409         for(set<Track *>::const_iterator i=ltracks.begin(); i!=ltracks.end(); ++i)
 410         {
 411                 unsigned tid = (*i)->get_turnout_id();
 412                 if(!tid)
 413                         continue;
 414
 415                 TurnoutMap::iterator j = turnouts.find(tid);
 416                 if(j==turnouts.end())
 417                         continue;
 418
 419                 unsigned path_mask = 1<<j->second;
 420                 const vector<Endpoint> &eps = (*i)->get_type().get_endpoints();
 421                 for(unsigned k=0; k<eps.size(); ++k)
 422                         if(eps[k].paths&path_mask)
 423                         {
 424                                 Track *link = (*i)->get_link(k);
 425                                 if(!obj.tracks.count(link))
 426                                         obj.add_track_chain(*link, link->get_endpoint_by_link(**i), turnouts);
 427                                 if(!obj.tracks.count(*i))
 428                                         obj.add_track_chain(**i, k, turnouts);
 429                                 break;
 430                         }
 431         }
 432 }
 433
 434 void Route::Loader::turnout(unsigned id, unsigned path)
 435 {
 436         turnouts[id] = path;
 437 }
 438
 439 } // namespace Marklin