Hearts of Iron IV

Hearts of Iron IV

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Professor Resource & Accurate Simulation
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2.320 MB
Mar 30 @ 5:02pm
Apr 5 @ 6:33am
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Professor Resource & Accurate Simulation


This is the first version of my accurate resource and simulation mod. The goal of this mod is to give you the most realistic world war 2 experience ever designed within the boundaries of the HoI4 Clausewitz engine.

The creation of this mod has taken hundreds of hours if not more due to hardcore scientific historical research. This is as real as it gets gentlemen. My mod intends to add Realism and accurate simulation within the Hearts of Iron 4 framework while staying as much vanilla like for the overarching themes and mechanics. No new stuff is added. It is vanilla tweaking and optimization for accurate history and simulation. If you can play vanilla you can play this, only your game will become much more "Real".

Here is what to expect (Major improvements):

All resources on the map are now completely accurate based on scientific source material. Each resource unit on the map is now a combination of either mining industry, refinement / strategic storage, smelting and / or blasting.
All industry on the map is now completely accurate based on scientific historical economic data: historic GDP data is converted to represent the weighted amount of civilian factories each nation has.
All production in game is now completely accurate based on scientific historical war production data, adjusted for HoI4 metrics.
All fuel consumption from vehicles, ships and planes is as accurate as humanly possible to calculate and adjusted for HoI4 gameplay metrics.
All building and infrastructure construction times have been balanced based on homebrew scientific world economic simulation formulas for the best realism-game balance experience.
Realistic population growth based on plotting historic demographic data.
Manpower from non-core is also increased based on historical data from foreign conscription and volunteer historic participation studies.

Here is what to expect (Minor improvements):

Division designer cheapened for maximum military creativity.
Slight political power daily increase to encourage diplomatic and alternative (realistic) gameplay.
Slight decrease in political power expenditure requirements to encourage diplomatic and alternative (realistic) gameplay.
Increased storage capacity for political power, command power, and military experience.
Realistic nuclear reactor construction times.
One less research slot at start for USA due to the economic (realistic) giant it is now.
Spy Agency better balanced designed and more spies.

What does this imply and what will happen?:

Economic warfare against Great-Britain as Germany (or other Axis powers) is now a viable strategy. U-Boats convoy raiding now actually works realistically, I.e. Doenitz was correct. Without foreign aid, Great-Britain will starve.

The Soviet Union is now highly dependent on foreign help and lend lease, just as in history.

Japan now has proper motive to go to war with the USA over oil and maritime supremacy. Japans economic situation is now highly accurate.

Strategic bombing is now a viable and correct methodology of waging war, as was in history.

Germany, as in history has a correctly simulated oil need scenario. The Romanian and Caucasus oil fields are of utmost importance.

Portugal and Spain now have the proper tungsten monopoly and are of strategic importance to all factions in the world.

All resources in Asia are correct, Southern China region has its historical important role restored.

Naval warfare is back and worthwhile.

Strategic importance of the Balkan region restored for its historic role in aluminum and chromium ore production.

Diplomatic gameplay, using politcal power and spy agencies as majors and minors became much more interesting.

Realism my dudes. Loads of fun and quality time. Combine this mod with Expert AI for the most awesome and epic HoI4 Vanilla esque WW2 simulated experience.

Kind regards,


(More description and explanation will follow soon)


I play using this mod combined with Expert AI and that works like a charm.
This mod does many changes through defines hence it should have large compatibly, however:
Resource changes is done through the states files, mods that change the map or states are not compatible. Further, mods that change buildings, production, fuel values, equipment values or research trees are most likely not compatible.
This mod is compatible with all visual/audio mods and mods that do not change the above mentioned files.
This mod is most likely not compatible with any of the large overhaul mods (road, kaiser etc etc)

////////For ease of use, translations\\\\\\\\

Die Erstellung dieses Mods hat aufgrund intensiver wissenschaftlicher historischer Forschung Hunderte von Stunden gedauert, wenn nicht sogar mehr. Das ist so real wie es nur geht, meine Herren.

Alle Ressourcen auf der Karte basieren jetzt vollständig auf wissenschaftlichem Quellenmaterial.
Alle Branchen auf der Karte sind nun vollständig auf der Grundlage wissenschaftlicher historischer Wirtschaftsdaten dargestellt.
Die gesamte Produktion im Spiel ist jetzt völlig korrekt und basiert auf wissenschaftlichen historischen Kriegsproduktionsdaten, angepasst an HoI4-Metriken.
Der gesamte Treibstoffverbrauch von Fahrzeugen, Schiffen und Flugzeugen ist so genau wie möglich zu berechnen und an die HoI4-Gameplay-Metriken anzupassen.
Alle Bauzeiten für Gebäude und Infrastruktur wurden auf der Grundlage hausgemachter wissenschaftlicher Weltwirtschaftssimulationsformeln ausgeglichen, um ein optimales Spielerlebnis zwischen Realismus und Spiel zu gewährleisten.

由於核心的科學歷史研究,這個模組的創建花費了數百個小時甚至更多。 這對紳士們來說是真實的。

現在,遊戲中的所有生產都是完全準確的,基於科學的歷史戰爭生產數據,並根據 HoI4 指標進行了調整。
車輛、船舶和飛機的所有燃油消耗都盡可能準確地計算和調整,以適應 HoI4 遊戲指標。

Создание этого мода заняло сотни часов, если не больше, из-за серьёзных научных исторических исследований. Это настолько реально, насколько это возможно, господа.

Все ресурсы на карте теперь полностью точны и основаны на научных источниках.
Вся промышленность на карте теперь полностью точна и основана на научных исторических экономических данных.
Все производство в игре теперь полностью точно основано на научных исторических данных о военном производстве, скорректированных с учетом показателей HoI4.
Весь расход топлива транспортных средств, кораблей и самолетов рассчитывается с максимальной точностью и корректируется с учетом показателей игрового процесса HoI4.
Время строительства всех зданий и инфраструктуры было сбалансировано на основе доморощенных научных
Pr0fessor  [author] 1 hour ago 
Do not be bothered that the launcher says this mod is for a different version. It should still be compatible. Everytime paradox does some minor updates or hotfixes they change the version number of the game and as a mod maker you have to manually reupload your mod to change the version number, which is just a cosmetic thing.

I cant be bothered to spend a couple of hours each time to reupload this mod just for a cosmetic version match check mark everytime paradox does a minor tweak or version change.

Have fun!
Vulpes Virtute 3 hours ago 
..Holy SHIT this mod looks amazing! And I was about to stop browsing and start a game too... Great job with the detail!
Nash Jul 4 @ 1:56am 

No rush, I still suck at navy! :D
Pr0fessor  [author] Jun 30 @ 2:51pm 

That is indeed weird. This map does not change anything AI related. My first assumption would be that this is caused by the Expert AI. However, I will update this mod for the next version asap. If I am not mistaken there were no any big changes, but you never know.
Nash Jun 30 @ 3:45am 
When I use this mod with Expert AI Germany does not have any ships in production.
justtxyank Apr 30 @ 7:48am 
Might I suggest exploring state type modding as well. One of the thing I have tinkered with is adding modifiers to islands to make building slower and particularly small islands being slower to build, particularly airbases. Airbases on pacific island were a major strategic advantage because building one took time.
Pr0fessor  [author] Apr 26 @ 2:23pm 
@Aigle, that is why I made airfields cheaper so you can construct more faster. I have yet to look into changing airfields capacity. I am not sure at the moment if or how such a change will influence the AI. I have a list of new updates and tweakers, once there is a decent amount I will update the mod. Thanks for playing my mod, I hope you have a good time.
Aigle2 Apr 22 @ 5:45pm 
Very nice mod. But airbases sizes must be increased to fit the new airplanes numbers to be usable
Pr0fessor  [author] Apr 9 @ 1:39pm 
@Amine, I need to look up the exact numbers. The biggest changes are in infantry weapons and support equipment. The goal was to roughly simulate 10% of actual historic production. There is a comment I made in the discussion forum maybe this helps to explain the reasoning some more. When I have the time I will add a image with the value changes.

(Another Post I Made);
Just something to ponder, the game can be tweaked so you can produce 1 to 1 from history. For example it is possible to make 119k airplanes as Germany (https://en.wikipedia.org/wiki/World_War_II_aircraft_production) , however then you run in to the problem of HoI4 not having that many possible airfields to build and accommodate that many aircraft in the game. Its always a trade of when trying to go "real" in this clausewitz engine and the HoI4 framework.

(Also good luck managing 1000 individual airwings, thats a massive amount of "clicking" and micro management.)

I tried to make it as real as possible.
Amine Alkaline Apr 9 @ 11:04am 
Hello @Pr0fessor ! If you were to estimate it, how much cheaper and more avalaible have you made the production of war materials like planes, tanks and others in compariso to base game hoi4 ? I love this mod by the way, big up to you