Requirements for Civilization IV ruleset

What would you like to see in Freeciv? Do you have a good idea what should be improved or how?
Post Reply
Ignatus
Elite
Posts: 644
Joined: Mon Nov 06, 2017 12:05 pm
Location: St.Petersburg, Russia
Contact:

Requirements for Civilization IV ruleset

Post by Ignatus »

Civilization IV is believed to be likely the best in many ways in the commercial game series, we would like some its features in our rulesets but yet can not. For the few features common with CivIII, go to the corresponding post.

Combat:
Simplifications that CivIV has are: all unit types have 100hp and there is no difference between attack and defense strength. Now, the changes:
  • Unit strength is proportional to current health.
  • Firepower depends on combatants' strengthes and for unit of s1 against one of s2 it is equal 20*(3*s1+s2)/(3*s2+s1), thus varies from 6 to 60. This helps to widen the region of not too certain combats. 1.52 patch has replaced actual strengthes here with full hp ones, and 1.62 brought them to the average of the values.
  • First strikes are rounds when only one side may suffer damage. Each unit has a number of them, the difference matters in the combat.
  • An attacker might withdraw from the combat in case it would lose otherwise. The probability depends on unit type and promotions (in Civ3, on veteranship).
  • Instead of veteranship, there is experience/promotion system. Promotions help different game aspects. Some promotions are got another way from type, build or effects; build experience bonus is also posdible. A promoted unit is healed 50% but unfortified. In the commercial game, 41 different promotions exist (some require some another).
    • The promotion-giving effects include unit superposition, like presence of a Great General nearby.
  • Cities have cultural defend bonus (walls act only against early units), normally growing alongside with city radius. This bonus can be reduced by bombarding the city, then it regenerates.
  • Thing closest to the former bombardment is attack with collateral damage; the difference is that there is a specific defender, and the least hp to remain (at a collateraly damageable unit or also the direcly hit one) and maximal number of units to inflict collateral damage depend on the damager. Damager strength is halved for collateral targets.
Cities:
  • All production kinds are produced separtately. If you switch from Warriors to Workers, you produce Workers from 0 shields, but can finish Warriors afterwards from what you have already invested. Obsolete productions are converted to gold automatically.
  • Cultural defense, see above.
  • Cities have healthiness and unhealthiness counters from terrain, population, buildings etc. (there is a basic health limit, fresh water gives +2 health, each citizen produces 1 unhealth, each flood plain tile produce 0.4 unhealth but a wood tile 0.5 health...). All the population exceeding the difference consumes extra food, and the city can't celebrate with such citizens. This is instead of aqueduct pop caps etc.
  • Unhappy citizens don't incite a rebel. They just refuse to work themselves (not related to resistance in a newly conquered city). Celebration rules are the same as in previous games. Free happy city size is adjustable by the difficulcy level.
  • Settlers and workers don't cost population. Instead, as long as the city produces such a unit, any its food surplus is converted into shields.
  • Also, you can suspend city growing voluntarily with a "Don't grow" check.
  • Slavery civic allows hurrying by whipping citizens, like in some Civ3 govs. It works here as well for wonders but with lower pop2shield ratio. Also, the shields are affected by usual production multiplying effects.
  • (Probably similar to Civ3) A city has an unhappiness counter. Unlikeable events like whipping a citizen increase it +10 per lost pop, and the simultaneous unhappy faces rise on (counter_value+9)/10. An unique Aztecs' building halves whipping unhappiness increments.
  • Cities produce Great People Points. After a city scores next threshold of gpp (increasingly big), a special unit appears that can give the player much advantage. There are 5 categories of GP, which one appears is random but gpp are also of 5 types and the type odds are proportional to the accumulated amount of each one.
  • Instead of corruption that reduces your incomes, your growing empire cities suffer increasing expenses summing:
    • Distance to the capital component (7 + p)*int(0.29*dist)/8 (halved with courthouse, removed at Communism)
    • Scale component, approx. (0.6 + 0.033*(city_pop - 1))*N_cities/2
    • Corporative expenses (4g per corp present go to its HQ)
    • Colonial expenses (for cities not on one continent with the capital)
    Here some more explanation, more precise info mb here.
  • Great people may be converted into super-specialist citizens (actually, mostly work as a building unbuildable another way, even no food consumed). Also, there are free specialists for some buildings (again, may be mostly dubbed bu usual building effect).
  • Percentages of religion believers are stored for a city (correction: percentages likely appear only in Civ5, in Civ4 it either is in the city or not).
Barbarians:
There are three stadies in the game. In the beginning, barbarians are animals that are generated one by one out of sight of any city or non-barbarian unit, out of 5x5 square around any (non-barbarian?) unit. Animals are different from other barbs in that they can't enter or attack cultural borders. Since a turn, regular barbarians appear the same manner (can be met earlier in huts) that are most like Civ2/Freeciv barbs; rare barbarian uprisings spawn packs of units, like in Civ3 (but no encampments). A while later, barbarian cities appear in no man's lands with the same limitation. Barbarians here are more clever managers then Freeciv ones, basically it's a regular AI minus diplomacy.

Resources:
  • Additionally to connectivity, strategic resources require tile improvements to be accessible.
  • Additionally to strategic and luxury resources, there are food resources that increase food and (with a certain improvement) health in connected cities.
  • Some resources double the production of some kind.
  • Additionally to tiles, you can get some resources from wonders or corporations. E.g. Broadway wonder produces 5 Hit Musicals.
Last edited by Ignatus on Thu Aug 29, 2019 7:12 pm, edited 6 times in total.
Ignatus
Elite
Posts: 644
Joined: Mon Nov 06, 2017 12:05 pm
Location: St.Petersburg, Russia
Contact:

Re: Requirements for Civilization IV ruleset

Post by Ignatus »

Civics:
Replace rigid governments system. You have groups of civics that cover different aspects of the empire's state and can practise any one civic (that you have studied) from each group in a time. If you change a civic, a turn of anarchy follows: city production, growth, and research are halted (the same happens if you change your state religion). If you change more than 3 civics in time, anarchy continues for two turns.

Civics have upkeep. Basic one is calculated for each group by slightly different formulae (depending on difficulcy, number of cities and total empire population, also halved if you have "organized" trait for the civic) and each civic can have one of four levels of cost (approximately from 0 to 3 of basic value). Explained here.

Religions:
  • You can found one of seven religions. One of your cities (not capital) becomes then its holy city and gets much benefits. If you have not founded a religion, you can use one founded by another civ.
  • Religions may spread automatically to cities having none, connectivity to the HC required. Otherwise, Missionary units can go converting people (they can enter peaceful neighbours while other units can't).
  • Religions are mostly simlar but each one has its own set of buildings. Apostolic Palace, that acts as early UN, needs state religion and similar city religion and is suspended (probably forever) if one or both of them change.
  • A civ can declare a state religion (must be present anywhere), this religion takes some benefits at cost of other ones. Other effects much depend on religious civic applied. State religions influent AI diplomacy.
  • A Great Prophet may construct a Shrine in a holy city that will give +1g for each city with that religion.
Corporations:
There are several world's companies that can be founded in the game. A founder builds the company's HQ in a city with a Great Person of necessary type. The corporation is then spreaded by Corporate Executives (spend unit and some gold to found in a city). Each city which uses the corporation converts some available spare resources to something useful; the HQ city gets 4g/corp.city each turn. The founder must think well if to use the benefits for their oun good or to sell them and get gold. Some corporations concur so hard that they can't share cities.

Trade routes:
The routes are automatic (computed once per turn) and one way, foreign routes can exist one per target foreign city, inner ones are limited only by the origin city outcoming trade route number. The route income at its start depends on the population of the dest.city and the distance (1 trade at least) and is modified by start city buildings. Routes can run by connectivity network (single connectivity type only) EDIT: only by that foreign territory that has Open Borders Agreement that also lets units to pass, some enemy sea vessels may block some tiles around. The automatic system is dull, I have suggested seemingly better one more based on Civ5.

Different types of connectiviry require techs to use (e.g. rivers are roads only with Sailing).

Resources are traded in Civ3 way though.

Borders and diplomacy:
  • Tiles accumulate culture for each civ influenting them. Normally, they get 1c/turn at outer city border radius and +20c/turn going inside (only the most influenting here city of each civ counts?). There are actions that once add culture to nearby tiles, most valuable is Culture Bomb by a Great Artist. The reason is: if you have >50% of tile culture, you claim the tile.
  • Vassal states are made by subduing enemy civs (certain civics required) or selecting your colonial cities to liberate; they must be on another continent then your capital. Human players hardly can get into vassals in Civ4. Vassals are good for diplomatic victory and for reducing maintenance costs; they control themselves but mostly unable to determine their foreign policies. They can cancel the agreement if they once find it necessary.
  • On diplomacy screen you see what specifically in you infuriates the AI.
  • UN wonder, additionally to diplomatic victory, allows to vote certain resolutions that, if accepted, everyone has to follow (in BtS you may act disloyal to them, but at cost).
  • There are ultimatums: make peace/declare war/trade embargo to X, adopt civic Y, convert to religion Z.
  • Random events like weddings modify AI attitudes.
Ignatus
Elite
Posts: 644
Joined: Mon Nov 06, 2017 12:05 pm
Location: St.Petersburg, Russia
Contact:

Re: Requirements for Civilization IV ruleset

Post by Ignatus »

Leaders and AI:
  • Unlikely to Civ3, several leaders are possible for different civs. They not only have different AI traits but also different flavours that help particular game aspects (e.g. Isabella I is a Spiritual and Expansive leader of the spanish, Spiritual leaders don't have anarchy changing civics and build temples twice faster, Expansive ones have +2 health in cities and produce twice faster granaries and harbours and a quarter faster workers).
  • The AI traits are a very developed system, including parameters from basic strategy type to minimal attitude level to listen to certain diplomatic requests.
  • Not related to a ruleset, but a cool fact: CivIV AI is not omniscent.
Ignatus
Elite
Posts: 644
Joined: Mon Nov 06, 2017 12:05 pm
Location: St.Petersburg, Russia
Contact:

Re: Requirements for Civilization IV ruleset

Post by Ignatus »

A bit more about CivIV city defense:
* Cultural and buildings defense don't stack: the bigger one is applied in each case (including which suffers from the bombardment).
* After a city is bombarded, it does not regenerate for current and the next turn (i.e. it's possible to bombard each second turn), then grows for 5% of its maximal value.
* In a newly conquered city, defense is fully regenerated.
* Each type of bombarders reduces the bombarded defense bonus on a fixed amount of percents ("accuracy" promotion adds another 8 p.p.).
* Bombardment is a safe by itself action for the bombarder.
* Bonus can be reduced to 0% (it is shown near the city).
* Bombardment uses up only 1 mp (but most artillery does not have more).
Bombarding units in CivIV are mostly the same ones that perform collateral damage ("Siege units"), you choose what action to perform. Also, ships and planes can bombard cities (but ships can't attack land units).
Ignatus
Elite
Posts: 644
Joined: Mon Nov 06, 2017 12:05 pm
Location: St.Petersburg, Russia
Contact:

Re: Requirements for Civilization IV ruleset

Post by Ignatus »

Spies:
  • In vanilla Civ4, they were limited in number to 4/civ.
  • Spies are invisible to other units until they fail a mission, so can't be attacked or interacted with any way. In BtS where spies appear much earlier, tbey are invisible to other units except other spies, and Great Spies are totally invisible.
  • Also in BtS you have civilization-wide counter of espionage points that can be spent on missions performed like in Civ3.
  • Players don't know who has performed a successful covert action of them.
  • Spy succes probability depends on number of units on target tile; even more it depends on presence of enemy spies nearby.
Ignatus
Elite
Posts: 644
Joined: Mon Nov 06, 2017 12:05 pm
Location: St.Petersburg, Russia
Contact:

Re: Requirements for Civilization IV ruleset

Post by Ignatus »

A fortifying unit defense bonus grows by 5% until the addition reaches 25%.
A "cottage" extra on a tile grow in some turns (game speed setting dependent) to another extras that give increasingly more gold bonus and more pillage bonus.
Post Reply