Follow the same path until another is significantly better

[r2c2.git] / source / libr2c2 / trainrouteplanner.cpp

diff --git a/source/libr2c2/trainrouteplanner.cpp b/source/libr2c2/trainrouteplanner.cpp
index e42e61838d4fdc0c7dfa74fe2aa7b451211c8421..d9eedd2d4daccd0d33224548325c594859c7777a 100644 (file)
--- a/source/libr2c2/trainrouteplanner.cpp
+++ b/source/libr2c2/trainrouteplanner.cpp
@@ -16,6 +16,7 @@ namespace R2C2 {
 
 TrainRoutePlanner::TrainRoutePlanner(Layout &layout):
        goal(0),
+       path_switch_bias(15*Time::sec),
        timeout(10*Time::sec),
        result(PENDING),
        thread(0)
@@ -147,7 +148,12 @@ void TrainRoutePlanner::add_steps(const RoutingStep &step)
 {
        list<RoutingStep> new_steps;
        step.create_successors(new_steps);
+       if(new_steps.empty())
+               return;
+
        new_steps.sort();
+       if(!queue.empty() && new_steps.front().cost_estimate<queue.front().cost_estimate+path_switch_bias)
+               new_steps.front().preferred = true;
        queue.merge(new_steps);
 }
 
@@ -518,13 +524,14 @@ bool TrainRoutePlanner::TrainRoutingState::is_viable() const
 
 
 TrainRoutePlanner::RoutingStep::RoutingStep():
+       preferred(false),
        prev(0)
 { }
 
 TrainRoutePlanner::RoutingStep::RoutingStep(const RoutingStep *p):
        time(p->time),
-       penalty(p->penalty),
        cost_estimate(p->cost_estimate),
+       preferred(false),
        trains(p->trains),
        prev(p)
 { }
@@ -570,13 +577,6 @@ void TrainRoutePlanner::RoutingStep::create_successors(list<RoutingStep> &new_st
                                create_successor(next, train_index, i, new_steps);
        }
 
-       new_steps.sort();
-       for(list<RoutingStep>::iterator i=new_steps.begin(); ++i!=new_steps.end(); )
-       {
-               i->penalty += 5*Time::sec;
-               i->update_estimate();
-       }
-
        if(entry_ep.paths!=train.track->get_type().get_paths() && !train.critical)
        {
                /* Create a waiting state before the track if there's at least one path
@@ -719,7 +719,7 @@ void TrainRoutePlanner::RoutingStep::advance(const Time::TimeDelta &dt)
 
 void TrainRoutePlanner::RoutingStep::update_estimate()
 {
-       cost_estimate = penalty;
+       cost_estimate = Time::zero;
        for(vector<TrainRoutingState>::const_iterator i=trains.begin(); i!=trains.end(); ++i)
                if(i->remaining_estimate>=0)
                        cost_estimate += i->wait_time+i->estimated_wait+((i->distance_traveled+i->remaining_estimate)/i->info->speed)*Time::sec;
@@ -748,6 +748,8 @@ bool TrainRoutePlanner::RoutingStep::is_goal() const
 
 bool TrainRoutePlanner::RoutingStep::operator<(const RoutingStep &other) const
 {
+       if(preferred!=other.preferred)
+               return preferred>other.preferred;
        return cost_estimate<other.cost_estimate;
 }