Formula analysis

[pmarc]

Units and buildings with progressive costs
Only the base production cost appears in the Civilopedia, but the production cost increment appears in the data files (units.xml or constructibles.xml) as "COST_PROGRESSION" parameters.

All values are reported as (base production cost + increment). In most cases (unless specified otherwise), the increment applies for any additional copy created (COST_PROGRESSION_PREVIOUS_COPIES in the data files).

Age-independent unit costs:
- Settler and UU replacements (50 + 20) * Note: Settler cost increments based on COST_PROGRESSION_NUM_SETTLEMENTS, so it includes conquered settlements. However, building a settler also increases the cost even before it goes on to settle a town.
- Trader, later age versions and UU replacements (40 + 20)
- Army commander (100 + 200) * Note: The free one you get at discipline counts, so the first one you build costs 300.
- Fleet commander (120 + 240)
- Squadron commander (140 + 140)
- Carrier commander (160 + 160)

Age-specific unit costs:
- Antiquity great people (30 + 30)
- Exploration great people (130 + 40)
- Exploration physician from plague crisis (100 + 20)
- Modern great people (290 + 50)
- Modern explorer (400 + 400)

Walls by age: * Note: Walls use COST_PROGRESSION_PREVIOUS_COPIES_CITY, which must mean they only increase on a per-city basis, but tbh I haven't played with them
- Ancient walls (60 + 20)
- Medieval walls (150 + 20)
- Defense fortifications (500 + 20)

 

[Acken]

Town to city conversion gold cost
I couldn't find this in the data .xml files, so just derived from in-game behavior. It doesn't seem to vary by age.

It's in the GlobalParameters (so yes it's the same for every age since no age xml modifies its values). Copy pasting:
TOWN_UPGRADE_BASE_COST 400
TOWN_UPGRADE_MINIMUM_COST 200
TOWN_UPGRADE_MAXIMUM_COST 1000
TOWN_UPGRADE_PER_POP_DISCOUNT 50
TOWN_UPGRADE_PER_CITY_COST 300
TOWN_UPGRADE_IF_CAPTURED_COST 2.0

 

[Krikkit1]

Patch notes(https://civilization.2k.com/civ-vii/game-update-notes/):

​

Food and Growth Rebalance​

We heard you loud and clear on this one, food and population growth needed some dev TLC. The old system for growth had some bottlenecks, making it a much less valuable Yield compared to Science, Production, Culture, etc.



So, in Update 1.2.0, we’ve reworked the underlying math to make Food a more reliable and rewarding Yield across the entire game. We’ve removed the hard cap that used to block growth when gaining Food, and changed the way growth scales. Instead of following a cubic formula, where costs ramped up fast, we’ve shifted to a quadratic curve, meaning your Settlements will still slow down as they get larger, but the pacing should feel more natural.



In a few bullets, here’s the impact you’ll see and feel with this update:

• Food-focused strategies are finally viable all game long.
• Food-focused civs and leaders like (looking at you, Pachacuti) will feel stronger and more fun to play.
• AI behavior has improved, since they can now leverage high-Food starts and avoid bottlenecks that used to limit their expansion. You may find you even need to turn your difficulty settings down a notch.

• Resource Balance Changes:
  • Dyes give +4 Happiness instead of +3.
  • Fish is no longer a Factory Resource. It is a Bonus Resource with the effect: +6 Food in Settlements with a Port, +3 Food in any other Settlement.
  • Tin is a new Factory Resource that grants a bonus to Growth Rate.
    • Dev Note: We like the boost of Growth Rate as an effect, but not in the numbers or scale that Fish was granting it.

• Mementos
  • Addressed a reported issue where Confucius’ Brush and Scroll Memento could cause Food needed to the next growth event to become 0 or negative.

So the Growth formula has changed...
also how the bonuses apply has changed... have they finally gotten it right and applied all the Growth bonuses as an additive multiplier instead of a subtractive one?

And it looks like the Town->City cost Parameters (base and per city) are per age...has the Maximum gone to per age?

 

[Acken]

So the Growth formula has changed...
also how the bonuses apply has changed... have they finally gotten it right and applied all the Growth bonuses as an additive multiplier instead of a subtractive one?

And it looks like the Town->City cost Parameters (base and per city) are per age...has the Maximum gone to per age?

Growth:
The new formula is Flat + Scalar * pop + Exponent/100 * pop^2
<Row Age="AGE_ANTIQUITY" Flat="5" Scalar="20" Exponent="400"/>
<Row Age="AGE_EXPLORATION" Flat="30" Scalar="50" Exponent="500"/>
<Row Age="AGE_MODERN" Flat="60" Scalar="60" Exponent="600"/>

To put things in perspective what used to take 2632 to grow to pop 8 will now put you to pop 10. And you'll get much more pop from there. The gap is a lot smaller, for example pop 10 -> 11 is 605 to 709 when it used to be 2055 to 2795.
On the other hand the first pops will feel slower until pop 5.

City upgrades: Yes 2000 and 3000 maximums.
Exploration:
<Replace name="TOWN_UPGRADE_MAXIMUM_COST" value="2000"/>
<Replace name="TOWN_UPGRADE_PER_CITY_COST" value="400"/>
<Replace name="TOWN_UPGRADE_BASE_COST" value="500"/>

Modern:
<Replace name="TOWN_UPGRADE_MAXIMUM_COST" value="3000"/>
<Replace name="TOWN_UPGRADE_PER_CITY_COST" value="500"/>
<Replace name="TOWN_UPGRADE_BASE_COST" value="600"/>

 

[Krikkit1]

City upgrades: Yes 2000 and 3000 maximums.
Exploration:
<Replace name="TOWN_UPGRADE_MAXIMUM_COST" value="2000"/>
<Replace name="TOWN_UPGRADE_PER_CITY_COST" value="400"/>
<Replace name="TOWN_UPGRADE_BASE_COST" value="500"/>

Modern:
<Replace name="TOWN_UPGRADE_MAXIMUM_COST" value="3000"/>
<Replace name="TOWN_UPGRADE_PER_CITY_COST" value="500"/>
<Replace name="TOWN_UPGRADE_BASE_COST" value="600"/>

So you get the minimum cost (200) for your second city (after capital)
in Ancient at Pop 10 (+6 per additional city)
in Exploration at Pop 14 (+8 per additional city)
in Modern at Pop 18 (+10 per additional city)

You get the maximum (assuming your town has a pop of 8) cost
in Antiquity on your 5th city (4 already)
in Exploration on your 6th city (5 already)
in Modern on your 7th city (6 already)