Advanced routing - how it works in the game

[universum]

When playing Super Bowl Express map, I started to wonder how to speed up long distance transport of passengers or goods. I have also wanted to switch to hard routing difficulty and needed to avoid any deadlock.

I started to study a simple problem. How many trains I can run safely between two places while only using a single platform in each city:

Getting from single train to two trains is easy:
*edit: removed two_trains_working_214.jpg*
You can also lay the double track only in the middle or in multiple places. If it was possible to setup tracks to only allow train in one direction, it would be possible to run three trains on this layout as well. Unfortunatelly, it does not work.

I started to look for ways how to get three trains working simultaneously. At first I could only come up with this layout:
*edit: removed three_trains_working_253.jpg*

Disadvantage turned out to be that one of the trains decided to wait at the beginning of the track instead of proceeding through it to next semaphore loosing time when the platform became available. Other big problem was that this setup required two platforms at each station so it would not really solve the problem.

Besides, when you need two platforms, you can just create second double track and get four trains running:

*edit: removed three_trains_working_253.jpg four_trains_working_131.jpg*
This gives you even more cargo capacity but you still need two platforms.

I have tried several other things, among others to create loop like this one but trains just ignored the longer route completely.

*edit: removed three_trains_working_253.jpg three_trains_lockup_285.jpg*
In theory this setup should have supported up to 5 trains running simultaneously.

Then I remembered that when playing Scrooge 1.0 scenario, I have used closed loop to transport wood from sawmill to Shady Hollow, then paper to Tinseltown and empty train to sawmill. When both places started accepting passengers, I added passenger cars to transport them as well. The trains picked up passengers in both Shady Hollow and Tinseltown and on the way to Shady Hollow, train stopped to add wood. This setup had benefit of having trains used 100%. The setup looked like this:

*edit: removed circular_track_161.jpg*
In the simple form, the track consisted of 6 segments and could support up to 5 simultaneous trains. Picture is actually showing 7 simultaneous trains running and to allow this, I had to split segments between stations into multiple smaller ones (we will return to this topic at the end of the post again).

[universum]

Then I got an idea which turned out to be a solution to the problem. I have realised, that I "can" force the game engine to route the trains through third stop. I have tested it on the same map as all previous ideas but you can easily imagine that the sawmill on the left is actually located in between two places and the trains only stop there on the way from B to A but there is direct track from A to B:

As you can see, there are 8 trains sharing single platform without getting stuck.

Following screenshot demonstrates the idea better. 5 trains in action.

It is important to make the stop on the way so that train has to reverse otherwise game engine might attempt to route the train from Los Angeles to San Diego through cattle ranch and cause deadlock (happened to me after adding 4th train). It is also possible to use two "waypoints", one for each direction. I am not exactly sure how the game picks which way to go, I suspect that length also plays role so if the cattle ranch was further away, it might work even if the train did not have to turn around.

It appears that train stops on semaphore when the next segment is occupied but sometimes also when the one next to next segment is in use. I could not figure out exact details but it may be linked to whether the segment is platform or not.

It is important to have the semaphores placed exactly but game does not let you place new ones or delete unnecessary ones directly. Fortunately, there is easy workaround:

To place new semaphore, just create a fork and then delete it. You will end up with the semaphore where the fork started.

To remove semaphore, you need to delete the track on either side and then rebuild it. This could be rather tricky when the track is already in use.

Above idea is not for every game but if you really need to speed up long distance transport, it works as long as the cities can generate the goods faster than two trains can houl it.

And to close the topic, one other solution which allows you to run three trains between two places using only one platform on each side:

This setup allowed me to run three trains too. Idea is that each platform has two way fork and each end is connected with both ends on the opposite side creating and X. My layout is really ugly but it proved that the idea worked. BTW. the warnings that trains are waiting too long are there because I had the trains set up to "wait till full" but the trains kept moving once fully loaded.

Looking forward to hear what you think about this...

(BTW. is there a way how to have pictures in the text but not showing up as attachments? I was thinking about deleting attachments but I am worried it would remove pictures from the server as well). It would be nice if attachments had option to "show as attachment".

[Warll]

Nice work! I knew some of the routes but not all of them and as to your question about the images you could host them on www.imageshack.us. Once you have them hosted use the tags to have them show up on your post.

[Dr Frag]

Wow, very interesting research. Hopefully I will actually understand it one day.

[Warll]

Would it be okay with you if I added this to the Wiki?

[Dr Frag]

I hope so, the Routing section is empty.

universum: Maybe this is a dumb question (I've only been playing for a week) but why do you want to stick with just one paltform?

[Warll]

Because if you can find one that can be easily up-sized it means you could have a any number of trains going through one station. For example the loop route can handle 8 or even more trains with one track. Now if you had 4 tracks going through a station you could have upwards from 32 trains to a station! Metros can not even produce enough goods to fill that many trains.

[Dr Frag]

Okay, scalability. Those kind of numbers are little out of my current level of gameplay though. It would be really kewl to see a 225 sq. unit map with that many trains running around. It would probably take a pretty impressive system to make it look good.

[snoopy55]

I've played a few games with more than 30 traiuns at the end. I worked to get every resource and town connected. The bad thing is slowness of the track installation by the computer nad the hihg possibility of CTD. These high numbers may be why some people quit when the screen seems to freeze. I can only figure that when you add a track it has to go over all of your existing track to lay the new one. The next time you plan to buyout and merge an AI with lots of track, lay a small piece, buyout nad merge, then lay another small peice. You should notice a difference.

[universum]

Hi Warrl,

sure, I have no problem with you adding it to the Wiki at all. I have also replaced one of the screenshots with better one.


Dr Frag,

yes, this is rather special case when you want to transport a lot of stuff between to distant locations and you want to make sure you are picking it as fast as the city can produce it. Exactly this is requirement in Super Bowl Express scenario where the distance is big and every track leads to Miami. Check the thread for some pictures of Miami:
http://www.hookedforums.com/a/viewtopic ... c&start=15

[Warll]

You can add the guide here: http://www.hookedgamers.com/w/index.php ... ction=edit