Border expansion bug?

[Juanholio]

In the attached pic there's a gold tile which has not diverted the cultural expansion of the city. The city has been in place for roughly 70 turns and even though I bought [had to buy] the tile adjacent to the gold quite some time ago (I forget the exact numbers), the expansion algorithm is still prefering what seem to me to be less valuable tiles (by both cities).

Usually I see that if there's a lux 3 tiles away and I buy the adjacent tile the lux is among the next cultural expansion targets. Not sure if this is a bug but it seems unusual behaviour.

 

[Barathor]

Yeah, I noticed this too. The cultural border expansion is still a bit off, even though it "is" better than the last version of the game. Coincidentally, I ran some tests a few days ago and found the same thing: it was favoring regular tiles over resources at times (luxuries even!).

This is an old thread I created on the issue which shows how silly it used to be before they supposedly fixed it in the patch:
http://forums.civfanatics.com/showthread.php?t=469674

I was going to post up a simple mod that fixes this behavior. I think with the value changes, along with the changes made in the patch, it should function the way it should.

 

[Juanholio]

Just read your previous post. Very comprehensive! There are significant improvements over what it used to be like.

I reasoned that desert hills probably aren't considered very valuable - even though the hills with mountains are valuable to the Inca. Though I don't expect it to take UAs into account at all. I bought the adjacent tile thinking it would 'notice' the gold and aquire it. After all it was a resource that was new to me (even though that's not considered - but a resource nonetheless). I got embroiled in a war and for got all about it. Many turns went by and it had consistently expanded into very ordinary tiles in the 3rd ring while the gold was just sitting there.

I think it would make sense for it to consider resources in the 3rd ring as a priority especially if you have 1-2 tiles adjacent - I don't necessarily expect it to 'move toward' 3rd ring resources in anticipation of aquiring them; rather it follows its rules for 2nd ring and if at that time a resource is adjacent in the 3rd ring in bumps up the priority a bit. So you could always still buy the tile if you weren't prepared to wait the 'natural' expansion time.

I think it might also be interesting if the expansion was slightly biased towards a nearby city closing the gap between them.

 

[Barathor]

I just ran some thorough tests. The new version is definitely an improvement and much smarter than before.

I don't necessarily expect it to 'move toward' 3rd ring resources in anticipation of aquiring them; rather it follows its rules for 2nd ring and if at that time a resource is adjacent in the 3rd ring in bumps up the priority a bit.

Actually, that's one of the awesome improvements Firaxis has made. For example, the city will actually prioritize 2nd ring tiles that are adjacent to a 3rd ring resource, when normally, they would be equal in influence cost to other 2nd ring tiles. It makes it less of a random shot to grab that adjacent tile so you can grab the resource next.

Another nice thing is that it seems to prioritize luxury resources over bonus resources. Though, sometimes it doesn't and I'm not sure whether it's because they were in the first ring or if it's another smart coding to increase the priority of bonus resources for the first couple acquisitions to get the city off to a good start.

But, with regards to luxury vs. bonus, another smart move which was pretty evident during the tests is that it won't care much for bonus luxuries that are past the 3rd ring and are unworkable, but luxuries it will go after -- which is the way it should be.

Anyway, with some tweaks, I greatly improved the order in which cities acquire tiles. You'll no longer come across those odd instances where a resource is adjacent to your borders, yet it's grabbing normal tiles.

I created two versions, one that is a "Lite" one and will simply fix the problem you ran into for players that don't wish to modify the base game too much or are wary doing so, and another version which further tweaks some more values to make the acquisition order very efficient.

I'm just polishing up the the two versions to a "publishable" state by writing some descriptions and creating some images.