Rewrite goal initialization for TrainRouteMetric

The previous code incorrectly added all tracks as goals when a direction
was specified, instead of only the ends.  This caused cost estimate creep
in the route planner, resulting in suboptimal performance.

diff --git a/source/libr2c2/trackchain.h b/source/libr2c2/trackchain.h
index 7102e5659445062765793ac5d349894f36a649db..74d194884e48eac531991f3f552bd95302abd612 100644 (file)
--- a/source/libr2c2/trackchain.h
+++ b/source/libr2c2/trackchain.h
@@ -72,6 +72,7 @@ public:
        bool has_track(Track &) const;
        virtual TrackIter iter_for(Track &, Direction) const;
        TrackIter get_end(unsigned) const;
+       virtual TrackIter get_end(Direction) const { return get_end(0); }
        bool is_loop() const;
 
 private:

diff --git a/source/libr2c2/trainroutemetric.cpp b/source/libr2c2/trainroutemetric.cpp
index 1fc4fcea2389d917ecaa90627791801dc0ee46e2..d3878d4aaec5d3b6dc875ee7b0453e0da82376f4 100644 (file)
--- a/source/libr2c2/trainroutemetric.cpp
+++ b/source/libr2c2/trainroutemetric.cpp
@@ -9,22 +9,28 @@ namespace R2C2 {
 
 TrainRouteMetric::TrainRouteMetric(const TrackChain &tc, TrackChain::Direction dir)
 {
-       /* Initialize goals for tracks in the target chain.  We travel outwards from
-       the target in the search phase so the iters appear to point the wrong way. */
-       TrackChain::Direction reverse_dir = (dir==TrackChain::DOWN ? TrackChain::UP : TrackChain::DOWN);
-       const TrackChain::TrackSet &ctracks = tc.get_tracks();
-       for(TrackChain::TrackSet::const_iterator i=ctracks.begin(); i!=ctracks.end(); ++i)
+       vector<TrackIter> ends;
+       if(dir==TrackChain::UNSPECIFIED)
        {
-               if(dir==TrackChain::UNSPECIFIED)
+               for(unsigned i=0; i<2; ++i)
+                       if(TrackIter end = tc.get_end(i))
+                               ends.push_back(end);
+       }
+       else if(TrackIter end = tc.get_end(dir))
+               ends.push_back(end);
+
+       /* Initialize goals for the ends of the target chain.  We travel away from
+       the goals in the search phase so the iters appear to point the wrong way. */
+       for(vector<TrackIter>::const_iterator i=ends.begin(); i!=ends.end(); ++i)
+       {
+               const TrackType::Endpoint &ep = i->endpoint();
+               unsigned nls = (*i)->get_n_link_slots();
+               for(unsigned j=0; j<nls; ++j)
                {
-                       unsigned nls = (*i)->get_n_link_slots();
-                       for(unsigned j=0; j<nls; ++j)
-                               if(Track *link = (*i)->get_link(j))
-                                       if(!ctracks.count(link))
-                                               goals.push_back(TrackIter(*i, j));
+                       TrackIter iter(i->track(), j);
+                       if(ep.has_common_paths(iter.endpoint()))
+                               goals.push_back(iter);
                }
-               else if(TrackIter iter = tc.iter_for(**i, reverse_dir))
-                       goals.push_back(iter);
        }
 
        list<TrackIter> queue;

diff --git a/source/libr2c2/zone.h b/source/libr2c2/zone.h
index fc44d4f205de91ad88bc3b7458310f2a39287996..cee45e8d311a29bd15b39ead3e2807aff5856189 100644 (file)
--- a/source/libr2c2/zone.h
+++ b/source/libr2c2/zone.h
@@ -49,8 +49,7 @@ public:
 private:
        TrackIter next_iter(const TrackIter &) const;
 public:
-       using TrackChain::get_end;
-       TrackIter get_end(Direction) const;
+       virtual TrackIter get_end(Direction) const;
 
        void save(std::list<Msp::DataFile::Statement> &) const;
        virtual Msp::DataFile::Statement save_reference() const;