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 "trackiter.h"
  14 #include "tracktype.h"
  15
  16 using namespace std;
  17 using namespace Msp;
  18
  19 namespace {
  20
  21 using namespace Marklin;
  22
  23 typedef std::pair<Track *, unsigned> Key;
  24
  25 struct Node
  26 {
  27         Track *track;
  28         unsigned ep;
  29         Node *prev;
  30         float dist;
  31
  32         Node():
  33                 track(0), ep(0), prev(0), dist(0)
  34         { }
  35
  36         Node(Track &t, unsigned e):
  37                 track(&t), ep(e), prev(0), dist(0)
  38         { }
  39
  40         Node(Track &t, unsigned e, Node &r, float d):
  41                 track(&t), ep(e), prev(&r), dist(prev->dist+d)
  42         { }
  43
  44         bool operator<(const Node &other) const
  45         { return dist>other.dist; }
  46 };
  47
  48 struct TrackMatch
  49 {
  50         Track &track;
  51
  52         TrackMatch(Track &t): track(t) { }
  53
  54         bool operator()(Track &t) const { return &t==&track; }
  55 };
  56
  57 struct TrackInSet
  58 {
  59         const set<Track *> &tracks;
  60
  61         TrackInSet(const set<Track *> &t): tracks(t) { }
  62
  63         bool operator()(Track &t) const { return tracks.count(&t); }
  64 };
  65
  66 template<typename Pred>
  67 list<Track *> dijkstra(Track &from, unsigned ep, const Pred &goal)
  68 {
  69         map<Key, Node> track_nodes;
  70         priority_queue<Node> nodes;
  71         Node *final = 0;
  72
  73         nodes.push(Node(from, ep));
  74
  75         while(!nodes.empty())
  76         {
  77                 Node lowest = nodes.top();
  78                 nodes.pop();
  79
  80                 Key key(lowest.track, lowest.ep);
  81                 if(track_nodes.count(key))
  82                         continue;
  83
  84                 Node &ref = track_nodes[key] = lowest;
  85                 if(goal(*lowest.track))
  86                 {
  87                         final = &ref;
  88                         break;
  89                 }
  90
  91                 const TrackType &type = lowest.track->get_type();
  92                 const vector<TrackType::Endpoint> &eps = type.get_endpoints();
  93                 const vector<Track *> &links = lowest.track->get_links();
  94                 for(unsigned i=0; i<eps.size(); ++i)
  95                 {
  96                         if(i==lowest.ep || !links[i])
  97                                 continue;
  98
  99                         unsigned link_ep = links[i]->get_endpoint_by_link(*lowest.track);
 100                         if(track_nodes.count(Key(links[i], link_ep)))
 101                                 continue;
 102
 103                         unsigned mask = eps[i].paths&eps[lowest.ep].paths;
 104                         if(!mask)
 105                                 continue;
 106
 107                         unsigned path=0;
 108                         for(; !(mask&1); ++path, mask>>=1) ;
 109                         nodes.push(Node(*links[i], links[i]->get_endpoint_by_link(*lowest.track), ref, type.get_path_length(path)));
 110                 }
 111         }
 112
 113         if(!final)
 114                 throw InvalidParameterValue("Could not find a route");
 115
 116         list<Track *> result;
 117         for(Node *node=final; node; node=node->prev)
 118                 result.push_front(node->track);
 119
 120         return result;
 121 }
 122
 123 template<typename Pred>
 124 Route *create_route(Track &from, unsigned ep, const Pred &goal)
 125 {
 126         list<Track *> tracks = dijkstra(from, ep, goal);
 127
 128         Route *route = new Route(from.get_layout());
 129         for(list<Track *>::iterator i=tracks.begin(); i!=tracks.end(); ++i)
 130                 route->add_track(**i);
 131
 132         route->set_name("Pathfinder");
 133         route->set_temporary(true);
 134
 135         return route;
 136 }
 137
 138 }
 139
 140
 141 namespace Marklin {
 142
 143 Route::Route(Layout &l):
 144         layout(l),
 145         temporary(false)
 146 {
 147         layout.add_route(*this);
 148         layout.signal_track_removed.connect(sigc::mem_fun(this, &Route::track_removed));
 149 }
 150
 151 Route::~Route()
 152 {
 153         layout.remove_route(*this);
 154 }
 155
 156 void Route::set_name(const string &n)
 157 {
 158         name = n;
 159         signal_name_changed.emit(name);
 160 }
 161
 162 void Route::set_temporary(bool t)
 163 {
 164         temporary = t;
 165 }
 166
 167 void Route::set_turnout(unsigned addr, unsigned path)
 168 {
 169         if(!addr)
 170                 throw InvalidParameterValue("Invalid turnout address");
 171         map<unsigned, int>::iterator i = turnouts.find(addr);
 172         if(i==turnouts.end())
 173                 throw KeyError("Turnout is not in this route");
 174         if(i->second>=0 && path!=static_cast<unsigned>(i->second))
 175                 throw InvalidState("Setting conflicts with route");
 176         i->second = path;
 177 }
 178
 179 void Route::update_turnouts()
 180 {
 181         set<unsigned> found;
 182         for(set<Track *>::const_iterator i=tracks.begin(); i!=tracks.end(); ++i)
 183                 if(unsigned tid = (*i)->get_turnout_id())
 184                 {
 185                         found.insert(tid);
 186
 187                         const vector<TrackType::Endpoint> &endpoints = (*i)->get_type().get_endpoints();
 188                         const vector<Track *> &links = (*i)->get_links();
 189
 190                         // Build a combined path mask from linked endpoints
 191                         unsigned mask = 15;
 192                         for(unsigned j=0; j<endpoints.size(); ++j)
 193                         {
 194                                 if(!tracks.count(links[j]))
 195                                         continue;
 196
 197                                 if(unsigned tid2 = links[j]->get_turnout_id())
 198                                 {
 199                                         const TrackType::Endpoint &ep = links[j]->get_type().get_endpoints()[links[j]->get_endpoint_by_link(**i)];
 200                                         int p = get_turnout(tid2);
 201                                         if(p>=0 && !(ep.paths&(1<<p)))
 202                                         {
 203                                                 // The linked track is a turnout and has a path which is incompatible with this endpoint
 204                                                 mask &= ~endpoints[j].paths;
 205                                                 continue;
 206                                         }
 207                                 }
 208                                 mask &= endpoints[j].paths;
 209                         }
 210
 211                         if(mask && !(mask&(mask-1)))
 212                         {
 213                                 // Exactly one possible choice, set the path accordingly
 214                                 unsigned path = 0;
 215                                 for(; (mask && !(mask&1)); mask>>=1, ++path) ;
 216                                 turnouts[tid] = path;
 217                         }
 218                         else if(!turnouts.count(tid))
 219                                 // More than one possible choice, and no existing entry - set as undecided
 220                                 turnouts[tid] = -1;
 221                 }
 222
 223         // Remove any turnouts that do not exist in the route
 224         for(map<unsigned, int>::iterator i=turnouts.begin(); i!=turnouts.end();)
 225         {
 226                 if(!found.count(i->first))
 227                         turnouts.erase(i++);
 228                 else
 229                         ++i;
 230         }
 231 }
 232
 233 int Route::get_turnout(unsigned id) const
 234 {
 235         map<unsigned, int>::const_iterator i = turnouts.find(id);
 236         if(i!=turnouts.end())
 237                 return i->second;
 238         return -1;
 239 }
 240
 241 void Route::add_track(Track &trk)
 242 {
 243         if(tracks.count(&trk))
 244                 return;
 245
 246         if(!tracks.empty())
 247         {
 248                 unsigned valid = check_validity(trk);
 249                 if(!(valid&1))
 250                         throw Exception("Not linked to existing tracks");
 251                 else if(!(valid&2))
 252                         throw Exception("Branching routes not allowed");
 253                 else if(!(valid&4))
 254                         throw Exception("Route must be smooth");
 255         }
 256
 257         tracks.insert(&trk);
 258         update_turnouts();
 259 }
 260
 261 void Route::add_tracks(const set<Track *> &trks)
 262 {
 263         set<Track *> pending;
 264         for(set<Track *>::const_iterator i=trks.begin(); i!=trks.end(); ++i)
 265                 if(!tracks.count(*i))
 266                         pending.insert(*i);
 267
 268         while(!pending.empty())
 269         {
 270                 bool found = false;
 271                 for(set<Track *>::const_iterator i=pending.begin(); i!=pending.end(); ++i)
 272                         if(tracks.empty() || check_validity(**i)==7)
 273                         {
 274                                 tracks.insert(*i);
 275                                 pending.erase(*i);
 276                                 found = true;
 277                                 break;
 278                         }
 279
 280                 if(!found)
 281                         throw Exception("Could not add all tracks to route");
 282         }
 283
 284         update_turnouts();
 285 }
 286
 287 void Route::add_track_chain(Track &start, unsigned ep, const TurnoutMap &trnts)
 288 {
 289         TrackIter iter(&start, ep);
 290         while(iter)
 291         {
 292                 if(iter->get_type().is_dead_end())
 293                         break;
 294
 295                 if(has_track(*iter))
 296                         break;
 297
 298                 int path = 0;
 299                 if(iter->get_turnout_id())
 300                 {
 301                         TurnoutMap::const_iterator i = trnts.find(iter->get_turnout_id());
 302                         if(i==trnts.end())
 303                                 break;
 304
 305                         path = i->second;
 306                 }
 307
 308                 add_track(*iter);
 309
 310                 iter = iter.next(path);
 311         }
 312 }
 313
 314 bool Route::has_track(Track &t) const
 315 {
 316         return tracks.count(&t);
 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(Track &trk) const
 327 {
 328         unsigned result = 4;
 329         for(set<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<TrackType::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(Track &from, unsigned ep, Track &to)
 384 {
 385         return create_route(from, ep, TrackMatch(to));
 386 }
 387
 388 Route *Route::find(Track &from, unsigned ep, const Route &to)
 389 {
 390         return create_route(from, ep, TrackInSet(to.get_tracks()));
 391 }
 392
 393 Route *Route::find(Track &from, unsigned ep, const set<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<TrackType::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                 break;
 433         }
 434 }
 435
 436 void Route::Loader::turnout(unsigned id, unsigned path)
 437 {
 438         turnouts[id] = path;
 439 }
 440
 441 } // namespace Marklin