HOI4 - Together For Victory AI Update #3

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Hi SteelVolt, what I would really like to see is an AI that is capable of using terrain specific units. Currently the terrain modifiers are much too low IMO, but you can't increase them because the AI doesn't know how to use them. Would it be so hard to have the AI assign mountain units to a theater with lots of mountains for instance or cavalry to deserts and tanks to plains? Not necessarily have them fight only in those tiles but at least assign the right units to the right frontline.

Even worse, the AI seems to be incapable of distinguishing between frontline units and suppression/garrison units.
Fixing this problem would go a very very long way towards improving the AI.
 
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This will seem incredibly vague I'm sure but has anything been done to address the German AI from going completely off the rails by 1940? We're talking things like declaring war on everyone it can all at once and inviting Finland into the Axis during the winter war thus starting a conflict with the Soviets early.

Apologies of I somehow missed a fix for this in proceeding diaries. Also apologies if that's going to be talked about later this week. I'm just getting antsy as this is my primary deal breaker. Right now I can't have a decent game of HoI4 unless I, myself, play as Germany. AI Germany is hopeless.
 
Of course, I cannot only leave you with only one point, even if it is a big one, so I will also use this diary to talk a bit about defensive AI.

- Split up AI garrison order in two: home area and other areas.
On this subject, are you per chance doing anything to split the garrison AI from the combat AI in the first place? As things are in 1.2, the AI pretty much repeatedly ruins its own plans, because whenever it decides to garrison area, it just grabs as many units as it deems needed from all over the place, which typically also means ongoing, active war fronts. So the front units wind up getting pulled away and strategically re-deployed half across continent, and then as soon as the movement ends they are sent back, because on the next re-evaluation the AI notices that hey, the fronts are now collapsing an/or understaffed. Cue another strategic re-deployment, and then every few weeks rinse, repeat. End effect: nothing ever gets effectively garrisoned, and the front operations are a mess.

Can't help but think the things would work far smoother if the countries had instead separate AI instance in addition to the current one, whose only area of responsibility/interest would be evaluating how many units are needed to garrison controlled areas, training units best suited for this task, and placing them in the relevant areas... working with unit pool completely separated from the regular army.
 
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Thanks for the info @SteelVolt

I have a question partly base on what you bring up here & defensive garrisons. If I were going to give an AI controled country a bunch of weak forces (maybe to defend low priority borders of Czechoslovakia or Poland or to defend the long coastline once Germany controls most of Europe or just to sit on VP provinces) through an event would the AI use them for lower priority duties and use the better forces for the major offensives/fromts?

The garrison order would grab the shittiest unit first, and then fill out with less shitty if it determined to need more divisions to cover the order, while the oposite is true for other order types. This is something I would like to spend more time on improving, but the intention is to concentrate weak forces in garrison orders and let the other orders grab the good ones first.
 
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Hi SteelVolt, what I would really like to see is an AI that is capable of using terrain specific units. Currently the terrain modifiers are much too low IMO, but you can't increase them because the AI doesn't know how to use them. Would it be so hard to have the AI assign mountain units to a theater with lots of mountains for instance or cavalry to deserts and tanks to plains? Not necessarily have them fight only in those tiles but at least assign the right units to the right frontline.

Even worse, the AI seems to be incapable of distinguishing between frontline units and suppression/garrison units.
Fixing this problem would go a very very long way towards improving the AI.

For the first point, the AI does try to determine the important terrain types when assigning units to orders. The theatres are not really a map concept in the background in HoI4, but rather a tool for players to organize their groups. At any rate, I agree that there is a lot of room for improvement, but not the main thing the AI has been failing with, and as such has not been a focus so far but will likely be part of future updates :)

Second point:

The garrison order would grab the shittiest unit first, and then fill out with less shitty if it determined to need more divisions to cover the order, while the oposite is true for other order types. This is something I would like to spend more time on improving, but the intention is to concentrate weak forces in garrison orders and let the other orders grab the good ones first.
 
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This will seem incredibly vague I'm sure but has anything been done to address the German AI from going completely off the rails by 1940? We're talking things like declaring war on everyone it can all at once and inviting Finland into the Axis during the winter war thus starting a conflict with the Soviets early.

Apologies of I somehow missed a fix for this in proceeding diaries. Also apologies if that's going to be talked about later this week. I'm just getting antsy as this is my primary deal breaker. Right now I can't have a decent game of HoI4 unless I, myself, play as Germany. AI Germany is hopeless.

I have not seen the things you talk about happen in my over night hands offs for a very very long time (at least in historical mode), so unless you as a Finland player manage to join the Axis and drag Germany into an early war with Soviet Union, I think it is pretty safe to say that this area is much better.

That is not to say there might not be other thing you would consider "off the rails", as what is and isn't is subjective.
 
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The garrison order would grab the shittiest unit first, and then fill out with less shitty if it determined to need more divisions to cover the order, while the oposite is true for other order types. This is something I would like to spend more time on improving, but the intention is to concentrate weak forces in garrison orders and let the other orders grab the good ones first.
Really great to hear as I have plans and I am glad the AI will make good use of them!
 
Nice DD!

I am curious on the encirclement detection:

Do you use flow networks to detract the potential bottleneck?
Out of my head I would guess you could use a sudden reduction in flow to front line provinces to lets say your capital as a predictor for an encirclement?
 
I have not seen the things you talk about happen in my over night hands offs for a very very long time (at least in historical mode), so unless you as a Finland player manage to join the Axis and drag Germany into an early war with Soviet Union, I think it is pretty safe to say that this area is much better.

That is not to say there might not be other thing you would consider "off the rails", as what is and isn't is subjective.

Here's a whole thread about what I'm talking about!

https://forum.paradoxplaza.com/forum/index.php?threads/germany-what-are-you-doing.973477/
 
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On this subject, are you per chance doing anything to split the garrison AI from the combat AI in the first place? As things are in 1.2, the AI pretty much repeatedly ruins its own plans, because whenever it decides to garrison area, it just grabs as many units as it deems needed from all over the place, which typically also means ongoing, active war fronts. So the front units wind up getting pulled away and strategically re-deployed half across continent, and then as soon as the movement ends they are sent back, because on the next re-evaluation the AI notices that hey, the fronts are now collapsing an/or understaffed. Cue another strategic re-deployment, and then every few weeks rinse, repeat. End effect: nothing ever gets effectively garrisoned, and the front operations are a mess.

Can't help but think the things would work far smoother if the countries had instead separate AI instance in addition to the current one, whose only area of responsibility/interest would be evaluating how many units are needed to garrison controlled areas, training units best suited for this task, and placing them in the relevant areas... working with unit pool completely separated from the regular army.

Depending on how you see it, it is already split up in a sense. But to do it as strict as you propose would be dangerous. Imagine a scenario where it would suddenly need to move 90% of the garrison units to the front in order to cover it, the AI would appear pretty damn stupid if it kept the garrison units in that order in stead of plugging the holes.
 
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Depending on how you see it, it is already split up in a sense. But to do it as strict as you propose would be dangerous. Imagine a scenario where it would suddenly need to move 90% of the garrison units to the front in order to cover it, the AI would appear pretty damn stupid if it kept the garrison units in that order in stead of plugging the holes.
That's the thing -- if the garrison AI is separate and has its own units, there should never be a situation where 90% of these units need to be moved to the front, because #1 these units are small, cheap and built with suppression in mind instead of combat ability, meaning they are useless on the front and would be of no use there, and #2 covering the fronts is responsibility of the combat AI, which has its own pool of units specifically made and optimized for this task. In this scenario getting the garrison units moved to plug holes in the front would be actually the last thing you want to happen -- because it'd only confuse the combat AI into thinking the front is secured, when it'd be "secured" with trash that any opponent would just sweep aside.

as it is, the very problem with the (lack of) garrison/front arrangement *is* the AI regularly decides to pull that 90% of garrison units to the front. As the result, countries like GER effectively sit on 100% partisan activity from 1940 onward, because garrison forces are never left to do some actual suppression, and instead get shuffled all over the place. And a result of *that* is they effectively cease to expand their industrial base, because all factories are stuck on repairing stuff that repeatedly get wrecked by the resistance running unchecked.

(they also mess up their production because AI thinks it's perfectly sensible to treat the damaged factories as if they're fully functional and so winds up with various equipment assigned to these perpetually damaged factories, and effectively never produces the stuff... but that's another story)
 
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That's the thing -- if the garrison AI is separate and has its own units, there should never be a situation where 90% of these units need to be moved to the front, because #1 these units are small, cheap and built with suppression in mind instead of combat ability, meaning they are useless on the front and would be of no use there, and #2 covering the fronts is responsibility of the combat AI, which has its own pool of units specifically made and optimized for this task.

The problem with totally specific divisions for suppression and combat is that you need to predict in advance how much suppression needs you will have 1 or 2 years down the line to set it up and prepare with templates and training. While a human might be able to do something like that after a few dozen hours of experience, it's not really something you could expect an AI to pull off.

It is more effective though given the current balance if it can be pulled off (since cavalry is 67% stronger per cost at suppression then infantry is).
 
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The problem with totally specific divisions for suppression and combat is that you need to predict in advance how much suppression needs you will have 1 or 2 years down the line to set it up and prepare with templates and training. While a human might be able to do something like that after a few dozen hours of experience, it's not really something you could expect an AI to pull off.
At the basic level you only need a simple garrison template, something the AI can start with, and then simple production loop -- "calculate how many units is needed to cover currently controlled territories; if you don't have this many units, train the extra ones you need". You don't need to plan for that 1-2 years in advance -- it takes 120 days to train cavalry division in the game, and if new territory is left without full, dedicated garrison for a few months while the units get trained, it's not the end of the world. If nothing else it's still definite improvement from the current situation where they just don't get garrisoned at all.
 
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You don't need to plan for that 1-2 years in advance -- it takes 120 days to train cavalry division in the game.

Assuming you have infinite extra infantry equipment to spare, How often does the 1.2 AI tend to have that in your experience?

Also do note that suppression needs fluctuate alot and pretty quickly in both directions. For example when I play as Japan I don't need to build garrisons early because I can plan ahead and know that once I annex China the partisans are gone, but with your strategy of building as need arises AI Japan would waste alot of effort in 37-39 building garrisons it has no use for until maybe 1942 with historical war declaration.

Another issue is that as partisan issues rise, you need more garrisons to suppress the same territory since adjacent areas increase the needs, so such an approach also risks to under-estimate your need 120+ days down the line.
 
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Nice DD!

I am curious on the encirclement detection:

Do you use flow networks to detract the potential bottleneck?
Out of my head I would guess you could use a sudden reduction in flow to front line provinces to lets say your capital as a predictor for an encirclement?
Short answer: no. As for how I have done it, I am sneakily going to sit on that as a trade secret ;)

Unfortunately I am not in a situationwhere I can take the time to go through a forum thread to verify if issues people are talking about are fixed. After release of 1.3, if there is anything you feel should have been fixed that you are unsure if it has been reported, I would encourage you to post about it on the bug forum :)
 
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Assuming you have infinite extra infantry equipment to spare, How often does the 1.2 AI tend to have that in your experience?
The game map has finite size, and the number of controlled states never approaches anything near infinity. As such, the equipment needs of garrison forces are relatively modest, and far smaller than what you'd need as equipment for regular combat units you'd wind up using as suppression force otherwise. If the AI has problem supplying even that, then it's a failure cascade in progress where the inability to equip garrison(s) is the least of problems :)

Also do note that suppression needs fluctuate alot and pretty quickly in both directions. For example when I play as Japan I don't need to build garrisons early because I can plan ahead and know that once I annex China the partisans are gone, but with your strategy of building as need arises AI Japan would waste alot of effort in 37-39 building garrisons it has no use for until maybe 1942 with historical war declaration.
Even in this scenario the units would still perform the work they're built for during the 1-2+ years the war last, and then they can be used in the other territories JAP would try to conquer. I don't think that's a waste; effectively this becomes 'building in advance' the AI can't otherwise do very reliably.

(on sidenote, the "resistance disappearing overnight if country gets annexed" is so gamey I really wish it was done away with)
 
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Short answer: no. As for how I have done it, I am sneakily going to sit on that as a trade secret ;)


Unfortunately I am not in a situationwhere I can take the time to go through a forum thread to verify if issues people are talking about are fixed. After release of 1.3, if there is anything you feel should have been fixed that you are unsure if it has been reported, I would encourage you to post about it on the bug forum :)

Yeah I understand, no worries :). I'm eager to get back into the game and plan to pick up the expansion this week! With luck whatever was causing the the oddities I experienced are gone!
 
- AI now attempts to detect and react to many encirclement opportunities, both against itself and against enemies.

AI is difficult stuff. One thing I have noticed is how the AI handles an encirclement that is created as part of an offensive action as compared to how I do. To be specific, suppose that as my army advances a few enemy divisions get encircled behind the front line. I am winning the battle and chances are all I need to do is attack the encircled divisions directly and quickly so that my units can get back to the front line asap. The AI on the other hand, seems to try to fully encircle the trapped units before attacking, and usually takes some time to plan that attack. If you go for the direct approach and actually the resistance is more stubborn than you had expected, you can just stop and go for a more planned and methodical solution.

Will the upgraded AI take a more aggressive approach to clearing pockets of encircled troops?
 
As such, the equipment needs of garrison forces are relatively modest, and far smaller than what you'd need as equipment for regular combat units you'd wind up using as suppression force otherwise.

That was my point. The combat units already in queue and reinforcements from war hog most of the equipment so very little is left for any garrisons.

Even in this scenario the units would still perform the work they're built for during the 1-2+ years the war last, and then they can be used in the other territories JAP would try to conquer. I don't think that's a waste

Nah, the AI don't need suppression during at war since battleplans move around enough frontline units to keep the areas suppressed anyways ;) :p

( and even if it did build garrisons specifically triggered by occupation needs they would be ready about right when the war ends ).
 
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