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EU4 - Development Diary - 24th of October 2017

Good day all. As we reach ever closer to the release for Cradle of Civilization which, as you know will be released on...wait, we haven't announced the date yet? Well keep your ears to the ground and you may hear something about that very soon™. In any case, running up to that we have a military mixed-bag of features coming with Cradle that we want to talk about today, as well as a guest appearance from our AI Maestro @Gnivom .

Firstly in Cradle of Civilization we are bringing the ability to Name Generals. Does what it says on the tin: when recruiting a general, you will be able to give them a custom name or roll the die to generate a random name for them. This courtesy is, of course, extended to Conquistadors, Admirals and Explorers.

Name Generals.jpg


As an additional free quality of life change in 1.23, the number of pips your leader may receive is detailed in the tooltip, showing the random spread they will get as well as any bonuses you may get from Ideas and other such modifiers.

Staying on the Military Tab, we can also show the interaction to Slacken Recruitment Standards which will let a nation gain manpower in exchange for allowing somewhat less qualified men into the army. 2 years' worth of manpower can immediately be made available at a cost of 5 professionalism. Naturally, a nation needs to have at least some standards of Professionalism in able to slacken them.

slacken.jpg


Another small addition we have in Cradle is the ability to have compact battle results. This has been requested by the community in the past so we decided to add it into the expansion for those who don't need more than the bare minimum information punctuating the slaughter of war. This can be toggled on and off in the options menu

compact.jpg


Finally, sticking with the military theme, let's talk Templates. They are pretty awesome and remove a lot of micromanagement of recruiting armies. In Cradle of Civilization this is taken a step further with the ability to Conform to Template. In the Unit View, an army can conform to a template that you have specified earlier. Upon selecting a valid template, all superfluous units will detached from the army while required units are built and march directly to merge with the unit.

conform template.jpg


As this feature requires the ability to make templates (an Art of War Expansion feature) to be of any use we are unlocking that feature for owners of Cradle of Civilization too.

Now I'm handing the mic over to the Maestro of AI @Gnivom , to talk about himself and the changes to the AI in v1.23 Persia Update.

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Black News Indeed

I have worked on EU4 since February 2016. For the last year or so, I have had the great honour of being the master of its AI. But all things must come to an end, and I have decided to move on to other adventures, outside of Paradox. It is therefore my equally great honour to present to you my successor, @mikesc . These last months, I have taught him what he needs to know, as I was taught last fall. This will be my last week, so today is a good time to talk some about the AI.

AI Improvements
There has been much AI work put into 1.23. I will mention a few improvements here, and for the rest you are referred to the upcoming changelog.

Building AI
This may well be the most notable change, at least for those of you who often play into the late game.

The AI has always been horribly bad at deciding where to build buildings, which means an experienced player could easily be many times richer and stronger than the AI after only 100 years, with the same development. This has now turned around completely. Instead of deciding buildings based on scripted rules, it now calculates precisely how much it will gain from building each building, convert all values to ducats, and consider how big a treasury they need for the return on investment to be worth it. The reaction from QA after their first handsoff game with the new building AI was “You have created a monster”. Indeed, late-game AI is extremely rich.

It probably undervalues manpower and forcelimit at the moment, but that may be for the best.

This doesn’t only make the game harder however, as an expanding player will get a lot of free buildings.

Power Balance Threat
One feature in the AI that I believe was added by Chaingun, is called Power Balance Threat (PBT). It means that each AI determines another country, if applicable, that it considers a long-term strategic threat/rival. It will then try to weaken this country in subtle ways, such as sending gifts to or guaranteeing their neighbors. Allies can also be picked as PBT. The algorithm for determining PBT focuses on large and/or quickly expanding nations. Since this very often targets the player’s nation, the algorithm has been explicitly prohibited from selecting the player’s country, except on Hard and Very Hard. My understanding is that this was to avoid the perception of the AI targeting the player because of it being the player. This block has now been removed on Normal difficulty as well.

You may now see even your allies act to slow down your growth, and some countries getting worse attitudes towards you, but don’t expect a huge difference.

Other Changes/Improvements
Many people have complained about the AI’s use of Edicts, and correctly so. From 1.23, it will spend a lot less money on Edicts.

AI aggressiveness has been slightly tuned down, especially when in debt.

Many small improvements have been put into the army AI. For example fixing many cases where it pathed through, rather than around, enemy armies (often leading to just cancelling the movement anyway).

Many more improvements will be found in the changelog.

I am currently spending my last week at Paradox trying to make some major improvements to army AI, that will be incorporated after 1.23.

Cheats

My personal opinion has always been that the AI should cheat as little as possible - that the player should play the game at equal terms with the AI. I believe the EU4 AI follows this philosophy more than any other strategy game I have played (at least on normal difficulty).

The cheats that do exist are typically not to make the AI more powerful, but to work as lubricant where the AI is not as precise as the player (which could be to avoid more complicated and bug prone code, or unnecessary computing power). A good example is the extra diplomat, which is only used for one-time actions. The obvious exception is the Lucky Nation bonuses, which are not available to the player.

So, let’s mention some of the cheats that do (and do not) exist:

There are maybe a dozen places in diplomatic AI, where it is nicer towards other AI in specific cases that make sense but could potentially be exploited by the player. It may for example call in allies as if with Promise Land clicked, without then being bound to actually give land. It will however try to give if possible.

The AI does not cheat with dice rolls in battles (or sieges, or anyplace else that I can think of)

The AI no longer cheats with Fort Maintenance, since a few patches back.
EDIT: There is still a bug that they can cheat anyway sometimes. See https://forum.paradoxplaza.com/forum/index.php?threads/1-22-2-vassal-not-paying-for-forts.1052067/ .

The AI doesn’t cheat with Fort Zone of Control. Nor was it ever meant to, although there has been at least one bug in the past where it could in rare cases.

Other than the Fort Zone of Control, the AI/Player cheats currently mentioned on the wiki are correct (to my best knowledge).

Additional considerations:

  • The AI may sometimes look up underlying numbers that are not available to the player.
  • The AI sometimes restrains itself to get a more historical outcome.
  • The AI is not allowed to pause the game, and has to play hundreds of nations simultaneously. Nor does it use the extra time it could get when the player pauses, or plays on speeds lower than 5 (so that behaviour isn’t affected by game speed).
/Gnivom

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Thanks a lot for that Gnivom. Next week we will have another guest speaker from the team to talk about a huge project we've undertaken for the game which, so far, we have managed to keep completely secret and will be rolling out with 1.23. See you then!
 
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I don't know if it's been addressed previously or not, but will these new mechanics (specifically Professionalism) affect the Idea Groups?

Military Drill, for example, seems like it would fit better with some sort of bonus to Professionalism than directly to Morale.
It is impacted by hiring generals, Drilling, events and decisions.
https://forum.paradoxplaza.com/forum/index.php?threads/replacing-the-naval-ideas-in-quality.1049263/

I tried, but alas. It seems drilling and professionalism will not be introduced to ideas (or policies).
 
Look guys... I enjoy your products and appreciate the content added to EUIV as much as the next person, but, I can't help but feel like these intricate little features and nuances - like Slacken Recruitment Standards - have compiled to create a really bloated, unwieldy game that inevitably results in tough bugs and poor balance. It's getting to be too big and unnecessarily complex. I know some of you want to make fresh content and build on your creation, and others of you want to keep the revenue rolling in, but really, slow it down. It's not all about packing in obscure little features and mechanics and DLC revenue.
 
Oh, I forgot to mention that the AI is now able to declare wars on overseas countries (such as Ottomans on The Knights, or Japan on Korea) again. (For two years it has been unable to, except against Primitives and in Independence, Coalition, and Religious League wars)

Oh well, I guess people might see it in the changelog...
 
Oh, I forgot to mention that the AI is now able to declare wars on overseas countries (such as Ottomans on The Knights, or Japan on Korea) again. (For two years it has been unable to, except against Primitives and in Independence, Coalition, and Religious League wars)

Oh well, I guess people might see it in the changelog...
I take it india will finally see some action?
Then again, declaring the war is one thing. Actually landing troops and winning is another.
 
RIP Jake,
We shall miss him.
RIP
...
Oh, wait, he is still here. Nevermind! ;D

@Gnivom It has been a honor, too, to have you as our Artificial Intelligence of the EU4... wait, are you even human?! :p :p :p
Regardless, good luck on your travels outside the great paradox of the Paradox!
 
Oh, I forgot to mention that the AI is now able to declare wars on overseas countries (such as Ottomans on The Knights, or Japan on Korea) again. (For two years it has been unable to, except against Primitives and in Independence, Coalition, and Religious League wars)

Oh well, I guess people might see it in the changelog...

Is this why Cyprus always survived?
 
What about convert manpower to sailors? It's a realistic option if your navy suffered a series of blows.

I think it would be cool to have it vice versa as well and that it could potentially determine the quality of your navy. I remember how this played a role in the Battle of Trafalgar where Britain had experienced sailors while many French sailors were actually landsmen, not suited for the naval warfare.

More to the point, French ships would have a strong infantry corps as mentioned in this passage I quote from a Wikipedia entry on the battle:

"A general mêlée ensued and, during that fight, Victory locked masts with the French Redoutable. The crew of Redoutable, which included a strong infantry corps (with three captains and four lieutenants), gathered for an attempt to board and seize Victory."

I'm not sure if naval warfare currently simulates boarding actions in EU4 but if we have chances of boarding action, if there is such a thing in this simulation, then using some manpower might give you a sort of an infantry corps on the ship but even then it would not guarantee a ship capture and would potentially reduce quality of a ship with respect to broadside actions because of the room taken up by infantry corps that could be occupied by sailors instead.
 
"Conforming to template" is the best news for a long time, thank you so much!

Should be implemented into [...] HOI too.
Slightly OT, but it is a HoI feature already. You can either change an existing template and all divisions with that template will change to the new template or you can create a new template and then switch to that template for each division individually.

@Topic: I like the AI changes. The rest doesn't impress me much, though...
 
Oh, I forgot to mention that the AI is now able to declare wars on overseas countries (such as Ottomans on The Knights, or Japan on Korea) again. (For two years it has been unable to, except against Primitives and in Independence, Coalition, and Religious League wars)

Oh well, I guess people might see it in the changelog...
Wait what