Disappearing trade routes (3.19)

Hi all,

I wanted to see if you guys thought this was a legit bug before posting it in the bugs forum, or maybe I am just missing something. I feel I understand trade routes pretty well and this seems wrong to me. If I'm not understanding something, or this is already known/reported then I apologize. I did a forum search and couldn't find any reference to this.

Background:

I was playing my usual Emperor/Standard/Fractal game and had 13 cities and 4 vassals, along with numerous open border agreements. I browsed through my trade routes and just felt that I had waaay too many domestic ones for the amount of open borders I had and cities on the map. A quick check to make sure the other civs weren' running merchentalism (I was in free market) and I felt something was wrong. The whole map had been uncovered at this point (late game) and everybody had all trade-spreading techs (astronomy, sailing,etc) I then noticed something really weird. I had open borders with Darius who had 5 lovely large coastal cities. I was getting trade routes with his two smaller cities, but NOT the three larger ones including his coastal capitol (these are intercontinental and have +150% years of peace so no chance of domestic ones being worth more.)

Anyways ... long story short, I go back over my previous saves for that game and find the point where I start losing my trade routes. It's when I took vassals and then liberated the cities back to them. All of the trade-routes which I had in the liberated cities just disappear - forever. They do not get relocated into other cities, they are just gone.

I then decided to go back over my previous games, loading saves and liberating vassal cities - same deal. Every time, very consistently, that I liberate a city, all the trade routes to foreign cities (for the liberated city) disappear - never to return.

Am I missing something here? Can someone else test this and see if its happening on 3.19 for everybody, or just me. I haven't played prior to 3.19 for a while so I don't know if this happened in previous versions. If it does get confirmed as a bug, I'd say its a pretty serious one (I was losing probably 100+ gold/beakers per turn in my empire last game) so should be reported on the bugs forum.

Thanks,
RedFury

could you post a save?

Save game attaached. Here's what I did, your mileage may vary.

Try to find out why the Persian city of Persopolis (top right-ish) is not getting a trade-route, whilst other smaller, less lucrative persian cities are (despite many domestic trade routes.) Also Anjar (belonging to saladin, top-left.)

Then goto Mesa-Verde. Note the trade-routes. Then liberate the city back to Sitting Bull. Trade routes to those cities no longer exist in your empire! End turn - still not there! I went fifty or so extra turns and any city which was the destination of a trade-route inside a city which I liberated, I no longer got that city as a destination for my trade-routes from ANY of my cities.

Hope this helps,
Red Fury

Is it possible that his cities are getting cramped by trade-routes from other civs?

I was under the impression that I am allowed 1 foreign trade route to each foreign city (open borders/ trade network connected/ non-mercantalism.) That is, provided I have enough trade route slots to go around. I don't think the trade routes of other civs have any affect on mine.

I still think its a bug - anyone else able to look at my save?
thanks,

RedFury

You don't have any harbors necessary for ocean trade in your original cities. Sitting Bull and Darius couldn't trade with you because your coastal and land routes are compromised by the lack of open border treaties to Hannibal, Alexander and Ragnar.

As far as I'm aware, harbours are not necessary for ocean trade, all you need is a coastal city and astronomy to allow trade across the ocean. So if the trading partner has open borders/coastal city (port)/non-mercantalism then there's a connection. Harbours simply increase the base trade income by 50% and add some health-resource bonuses. edit : also you or your trade partner need to have explored every square of a route between the two cities.

Secondly, I don't believe my lack of open borders with Ragnar, etc would have any effect on trade routes with Darius, since I know astronomy so can trade across the ocean with him. If you look closely in my original cities you'll see that I *AM* getting trade routes with Darius, so there's no connection problem there at all. The problem is that I'm trading with some of his smaller, less lucrative cities and missing the larger coastal ones. Considering all of his cities are connected and I can use astronomy to connect with one coastal city, this makes no sense at all IMHO.

Thanks for your input, but I still see a bug...

RedFury

Let me put it another way for people who aren't getting what I'm saying.
How many reasons can you think of for why your civ would have connections with *some* cities for an AI, but not all of them.

I can think of three:
1) I don't have enough available trade routes
2) My domestic ones are worth more.
3) Not all the AI's cities are connected to his capital

In the case of my save we get large bonuses for years of peace and intercontinental trade to Darius, so 2) is not going to be the case. You'll also note I have a lot of domestics happening so 1) is not an option here either. Also, Darius only has 5 cities and they're all connected to each other, so strike 3).

RedFury

on 3) you can have only 1 trade route for each foreign city, at one of your cities.

overall it seems that there's a bug. i've noticed this stragne trade routes distribution too

killmeplease said:

on 3) you can have only 1 trade route for each foreign city, at one of your cities.

Click to expand...

Yep, absolutely. So I would expect to have 5 trade routes (1 to each of his cities) in my entire empire. I only have 3, which wouldn't be a problem if I've run out of available trade routes, but I haven't. Of more concern, its not the best/biggest cities getting the routes.

killmeplease said:

overall it seems that there's a bug. i've noticed this
stragne trade routes distribution too

Click to expand...

Yeah, there is definitely something going wrong here.
Edit: The best example of this, which I stated in my original post is why Persopolis is not getting a route, when I have heaps of low-earning domestic routes and the existence of other routes to Darius clearly show I am connected to him.

RedFury

Yup, definitely a bug -- nice find, RedFury .

Calling isTradeRoute(0) for Persepolis still returns true, i.e. the game thinks that you already have a trade route to Darius' capital and thus cannot assign it again. The same happens for Susa and Ecbatana after liberating Mesa Verde --> your "zombie" city Mesa Verde won't release these trade routes.

If you give yourself Cristo Redentor via WB, switch to Mercantilism, liberate Mesa Verde, and then switch back to Free Market on the next turn, you will regain = not lose the trade routes to these two cities of Darius'.

I can't test it right now, but I assume a simple call of CvCity::clearTradeRoutes() in CvCity::kill() (called for your old city during liberation) might solve the problem.

BTW in case you lose a city during war to a conquering neighbor, the target trade routes of this city will also be lost *forever* --> recapturing the city will not bring the trade routes back .

Thanks DanF5711, nice to know my understanding of what should happen with trade routes is correct.

Does anybody have any knowledge on an unofficial patch being worked on for 3.19 to fix these kinds of things? I'm not banking on Firaxis releasing another patch. I make my living as a C/C++ programmer so would love to jump into the code myself at some stage, the problem is just getting the time.

Cheers,
RedFury

there is a subforum for this

How bizarre! Thanks RedFury and DanF5771 for sticking through and figuring this out, will get in to next UP.

awesome guys! Where would a civ fanatic be without this community!! I had somehow missed that that forum even existed! Gonna download current UP now.

thanks,
RedFury