Anyone know how it chooses what tile to expand to?

[Victoria]

You may be right.

I may be, but it's not really me as I have not checked myself. I trust @KrikkitTwo in the formula thread who says that it is so. I'll try and be like the kiwi camel and pay better attention.

 

[valamas]

I wish i could select/override the AI controlled next hex. I often plan to wait for a hex but then the AI changes its mind, which of course screws with my plans.

If recall in Civ 5 that the AI did not change its hex decision.

 

[Forster]

I don't have any saves showing the delay. I never really paid it much attention until a hex with iron was due for expansion in, I think, 4 turns. The problem was I needed it to upgrade and a German settler protected by an archer was heading for my border. If it had settled I]t would take the hex. I bought it, upgraded and then noticed another the city had not expanded into another hex after the 4 turns had gone by. I try not to buy an expansion hex if it is anywhere near the time to pop.

 

[Victoria]

So why has my game just expanded like this? It just expanded into the wonder while I expected the whale

 

[Uberfrog]

So why has my game just expanded like this? It just expanded into the wonder while I expected the whale
View attachment 480006

Search me. Perhaps there's just a significant random element, or else it values sea wonders (Ha Long Bay) as being less than land wonders (Piopiotahi)?

Civ VI: Never Knowingly Transparent.

 

[King Rad]

Would it be too much micromanagement for us to be pick ourselves? A culture civ with this ability might be a nice perk, if it isn't too tedious

I suggested in another thread that being able to have the 'governor' pick a specific tile for expansion, but allowing him/her to pick if you didn't want to do this yourself would be a good idea in my opinion. It's like was also stated elsewhere, if I have a specific agenda with a city, then the normally best tiles might not be what i'm interested in. I'd let the game pick the tile, but give me the option to override if I so desire.

 

[nzcamel]

So why has my game just expanded like this? It just expanded into the wonder while I expected the whale

Weird. Maybe they haven't discriminated between natural wonders that can themselves be worked, and ones who can't be worked, but provide benefits to adjacent tiles.
That distinction would be a good one to make in terms of expansion priority!

 

[Spudsie74]

Coupla observations: I don't have any concrete evidence, but it seems to happen frequently enough...

Placing a worker+combat unit on a hex (with expansion potential) appears to cause the AI to change from a selected (expansion to hex in 5 or less turns) hex to the hex occupied by the worker+fighting unit provided the hex has "potential."

Yes, this is vague, I have observed (1700 hrs play) that when a city is about to expand to a given hex, and I get ready to work a different (equal value or better) hex, the AI frequently expands to the hex containing my worker, instead of the hex previously indicated. It happens often enough that I will avoid purchasing a hex, and simply occupy it (w/ worker+escort unit). If the city expands to the original hex, then I'll buy the hex I selected. Most of the time, it appears to switch to the hex I favor. Anyone else note this happening?

 

[cvb]

So why has my game just expanded like this? It just expanded into the wonder while I expected the whale
View attachment 480006

First of all, I think it would help to turn on yields ...

Placing a worker+combat unit on a hex (with expansion potential) appears to cause the AI to change from a selected (expansion to hex in 5 or less turns) hex to the hex occupied by the worker+fighting unit provided the hex has "potential."
Yes, this is vague, I have observed (1700 hrs play) that when a city is about to expand to a given hex, and I get ready to work a different (equal value or better) hex, the AI frequently expands to the hex containing my worker, instead of the hex previously indicated. It happens often enough that I will avoid purchasing a hex, and simply occupy it (w/ worker+escort unit). If the city expands to the original hex, then I'll buy the hex I selected. Most of the time, it appears to switch to the hex I favor.

Oooops, maybe you unwrapped prematurely Ed's next Easter egg???

 

[Art Morte]

This isn't really on topic, but not worth a thread, either: Peter's land-grab ability produced a rather stupid and annoying effect in my previous game. He founded a city in a place that was already surrounded by borders pretty much on all sides, there was only a corridor leading five hexes away from his newly found city, so the city grabbed that only available land up to five tiles away, putting a Russian border wedge between two of my cities. Grabbing land up to three hexes is fine, but I don't think his land-grab ability should extend further than that in a case like this, it's a bit ridiculous.

 

[Spudsie74]

Well, it looks like it is "all of the above," with a bit of randomness added to keep us guessing. I have no idea how it works, but it appears to favor: 1) Hexes you would normally grab, 2) Hexes that are not your first choice, but not too out there, 3) Hexes that have some conceivable appeal (military, geographic, wonders, ect. and 4) Hexes that it takes just to piss you off.

Good replay value...I guess if they let us look under the hood, we might install some parts that are not kosher.

 

[Spudsie74]

I have noticed a couple more things: It seems to favor hexes with the highest total yields (food+production+gold+culture+science+faith).
Given equal sums, 2 food + 1 culture is favored over 2 food + 1 production. (Same for faith & science).
It tries to give you some surplus food, 2 or ore if possible (e.g. defaults to avoid popo. loss).
There is some randomness (it changes its' mind, at least in games where I checked).
Putting a unit on a tile (that is a good pick) increases the chance it will be selected.
Water tiles (not adj. to wonders) are less likely to be chosen.
It appears that proximity to an enemy city (or CS) influences the choice. E.G> It will prioritize a (hihg value) tile near an enemy city over a similar tile elsewhere.
Not sure how it evaluates natural wonders: there is a disconnect between the wonder & the adjacent premium (extra value) tiles.
The AI is bipolar, or at least, has some issues.
.

 

[Eagle Pursuit]

I've always thought the tile logic was:
1) get the tiles in the 2nd ring with resources (randomly choosing among those)
2) get the tiles in the 2nd ring which are adjacent to resources in the 3rd ring (randomly choosing among those)
3) get the rest of the tiles in the second ring (randomly choosing among those)
4) once the 2nd ring is full, repeat steps 1-3 with the 3rd ring

 

[Archon_Wing]

Well, there's always Civ IV's way of just moving an entire ring per tier but it takes longer. That made the most sense and had the funny effect of also taking people's cities if your culture was too strong. However it also gave a tactical advantage since it made your borders harder to enter for war.

 

[Spudsie74]

Honestly, this is one of those things which are needless complicated in this game. Why they don't use a formula like this is beyond me:
Sum all the yields on that tile (with some weights, so that gold is worth 0.5, prod/food is 1.0, and the others 1.5; all tiles worth at least 0.5) and divide by the total movement cost (including roads) from the city centre to that tile. Pick the tile with the highest score.

It's straight forward, simple and easy to understand. It favours tiles with high yields that are close by. It relegates mountains/deserts to the end. There's a penalty for 'crossing a river' (until you've build a district on the other side that creates a bridge) or getting to difficulty terrain. Your borders naturally follow the roads made by your traders. You can influence it by chopping forests/building roads, but you can't direct it, so gold buying is still important.

When I finally get around to making my own indie game, this is exactly what I'll do: simple, transparent and intuitive formulas.

That would be way too easy.

 

[Spudsie74]

So why has my game just expanded like this? It just expanded into the wonder while I expected the whale
View attachment 480006

Actually, I may have a clue. It likes the bonus hexes (adjacent to wonder. It MAY have grabbed the wonder her because 1) The AI is bipolar (doesn't value sea resources as highly, and 2) Has an affinity for tiles that are adjacent to wonders, thus having extra goodies. (Count total number of all resources...include culture, science, faith, ect.). Under this (odd) theory, it took the resource to get (next time) access to the tile with the stone, adjacent to 2 natural wonder hexes (valuable for some district bonuses). If I had the $,I'd buy the quarry hex, harvest the rocks, and put as HS or Campus there.