+void Layout::add_vehicle(Vehicle &v)
+{
+ if(vehicles.insert(&v).second)
+ signal_vehicle_added.emit(v);
+}
+
+void Layout::remove_vehicle(Vehicle &v)
+{
+ if(vehicles.erase(&v))
+ signal_vehicle_removed.emit(v);
+}
+
+void Layout::tick()
+{
+ if(driver)
+ driver->tick();
+
+ Time::TimeStamp t = Time::now();
+ Time::TimeDelta dt;
+ if(last_tick)
+ dt = t-last_tick;
+ last_tick = t;
+
+ for(map<unsigned, Train *>::iterator i=trains.begin(); i!=trains.end(); ++i)
+ i->second->tick(t, dt);
+}
+
+void Layout::emergency(const string &msg)
+{
+ if(driver)
+ driver->halt(true);
+ IO::print("Emergency: %s\n", msg);
+ signal_emergency.emit(msg);
+}
+
+void Layout::save(const string &fn)
+{
+ IO::BufferedFile out(fn, IO::M_WRITE);
+ DataFile::Writer writer(out);
+
+ if(!base.empty())
+ writer.write((DataFile::Statement("base"), base));
+
+ for(set<Track *>::iterator i=tracks.begin(); i!=tracks.end(); ++i)
+ {
+ DataFile::Statement st("track");
+ st.append((*i)->get_type().get_article_number());
+ (*i)->save(st.sub);
+ writer.write(st);