+void TrainRoutePlanner::RoutingStep::create_successors(list<RoutingStep> &new_steps) const
+{
+ RoutingStep next(this);
+ if(next.update_states())
+ {
+ if(next.check_deadlocks())
+ return;
+
+ new_steps.push_back(next);
+ return;
+ }
+
+ int train_index = find_next_train();
+ if(train_index<0)
+ return;
+
+ TrainRoutingState &train = next.trains[train_index];
+
+ Time::TimeDelta dt = train.get_time_to_next_track();
+ next.advance(dt);
+
+ if(train.check_arrival())
+ {
+ new_steps.push_back(next);
+ return;
+ }
+
+ train.advance_track(0);
+
+ const TrackType::Endpoint &entry_ep = train.track.endpoint();
+ if(train.critical)
+ {
+ train.path = train.track->get_type().coerce_path(train.track.entry(), train.track->get_active_path());
+ train.update_estimate();
+ next.update_estimate();
+ if(next.is_viable())
+ new_steps.push_back(next);
+ }
+ else
+ {
+ for(unsigned i=0; entry_ep.paths>>i; ++i)
+ if(entry_ep.has_path(i))
+ {
+ train.path = i;
+ train.update_estimate();
+ next.update_estimate();
+ if(next.is_viable())
+ new_steps.push_back(next);
+ }
+ }
+
+ 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)
+ {
+ RoutingStep wait(this);
+ wait.advance(dt);
+ wait.trains[train_index].state = WAITING;
+ wait.penalty += 15*Time::sec;
+ wait.update_estimate();
+ if(wait.is_viable())
+ new_steps.push_back(wait);
+ }
+}
+