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HOI4 Dev Diary - Fuel

Hi everyone! We have now been working on Man the Guns for a bit and it is time to kick off dev diaries again!

For those who missed it, Man the Guns is the expansion we are currently working on. The main theme is naval warfare and it will be accompanied by the 1.6 ‘Ironclad’ free update. There is no release date yet. We will let you know when we can commit to a date :)
So without further ado, rev up your engines! Today we are going to be talking about fuel...

Fuel is something we originally decided to abstract into the production of vehicles in HOI4. The reasons for this were twofold: It simplified things, making the game easier to get into and learn and it avoided issues with fuel stockpiling in HOI3 (I’ll get to that later). I still think these were worthwhile tradeoffs with the gameplay impacts it had, but some areas, particularly naval warfare, never felt right without an overall worry over a supply for fuel, which essentially drove Japanese war planning historically. This in combination with a feeling that our fans can for sure handle a little nudge towards complexity now kinda cemented the idea that we couldn’t really make a naval expansion without expanding on this area.

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(no numbers are final etc ;))

Land
Fuel is used by trucks, tanks and other land equipment with engines in your divisions. They will use much more when fighting and moving than when stationary or during strategic redeployment (in fact right now those consume no fuel, but that might change with balance work). A division carries a bit of fuel with it ( much like how supply works), so there is a short grace period if cut off. If a division is in bad supply it will refill its fuel more slowly (meaning you won’t be able to attack or move rapidly as frequently), and you might even be unable to refill at all if totally cut off. Being without fuel will negatively affect the stats of the battalions that need it as well as severely impact speed depending on how low they are.
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Air
Your active air wings will consume fuel. The amount will naturally depend on the type of plane (strat bombers love to guzzle down that fuel) but also what mission type. Planes on interception will be very fuel efficient as they only take off when there are enemies attacking ground targets or bombing etc. Transport planes on air supply missions will also be able to deliver fuel to pockets etc. When low on fuel air wings suffer big efficiency penalties.

Sea
Running a lot of active capital ships is something you will need to be careful with in Man the Guns. These behemoths will be going through your fuel stockpile like starved baby whales on the teat. To handle this and make fleets act more realistically and in a more controlled manner we have changed quite a bit here, so stay tuned for future diaries. The main point is that big fleets are costly to run and you will need to make decisions on how to best utilize them and how much to fit into the rest of your fuel use. Speaking of, you’ll be able to control who gets first dibs on fuel through prioritization just like with equipment (but we are also working on adding extra controls on top of this so you can more easily balance between the different branches of the armed forces). A fleet that is low on fuel will suffer penalties to its stats as well as operational range.


Production
Fuel is produced from unused oil, and equipment that used to use oil now no longer need that to be produced. I am currently looking into possibly adding copper or another resource in its place (and in some other places), but we will see if that ends up being a good idea or not ;) Will let you know. Anyways, if you are low on fuel there are several ways to go:
  • Acquire more oil rich states.
  • Increase infrastructure on your own oil rich states.
  • Trade for foreign oil.
  • Build synthetic refineries.
  • Lend leased fuel.
  • Capture enemy stockpiles.
  • Research improved oil to fuel conversion technologies.
  • Each unit of oil you have access to use your current techs to generate a certain amount of fuel. This fuel is then put into your stockpile for use by your forces.
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Stockpiling
Fuel is possible to stockpile, in fact it is necessary if you can’t guarantee a steady stream of produced fuel during wartime. The size of your national stockpile will depend on the number of states and their infrastructure, your economic law and if you have built Fuel Silos. This is a new building that takes up shared slots and will probably provide the majority of your stockpile space. It is also a building that can be damaged from bombing etc. which in the worst case could lead to a loss of fuel. Capitulating enemy neighbors is also going to be a good way of acquiring more fuel as it will work just like seizing their equipment stockpile in that respect.

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HOI3 also had stockpilable fuel, and there it was quite a problem. As a beginner you did not know how much (or even that you had to) stockpile and as an experienced player there was no issue in making a stockpile big enough that you wouldn't ever have to worry. In HoI4 we are aiming to force a tradeoff between building up your industry and increasing the stockpile (have to spend civilian factories to get more oil from trade instead of building more factories) as well as trying to keep the total amount you can stockpile within reasonable bounds. Our goal is fuel as something you’ll need to consider for all your operations and playing it really safe will mean less industrial output in the long run.

Since I bet this will be the first question, fuel is going to be in the free update, but there will of course be features in the paid expansion that tie into it (stay tuned for more diaries!).

We are still working on all things fuel so I’ll wrap up here. Hopefully it gave you an idea of what we have done and are planning to do. I’ve saved some interfaces talk for future diaries, and also, be aware that many things could end up changing based on gameplay feedback. Rest assured though, I’ll keep you updated on stuff like that in these diaries up to release. This is not really anything out of the ordinary, but I usually keep systems like this that need long term balance and iteration for later. Fuel however ties into a lot of future topics, so I wanna make sure you are all clued in :)

Now for something completely different...
I assume nobody has managed to avoid having their mailbox fill up with fun updated privacy policies and things related to the new European General Data Protection Regulations (GDPR). During all this a really smooth looking lawyer dog in the smartest little suit I have ever seen came over to visit us from Brussels. He told us there are a bunch of regulations we too need to follow in our games… so to make sure we remained Good Boys in the eyes of the law we have added a couple of things to Hearts of Iron IV. The most important is to include our Privacy Policy in the game and making it easy to find.
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Legal texts are long and boring and nothing has really changed in how we do things. So I would rather spend my time answering questions here and writing the rest of the diary, so I will refer you to check it out ingame or here if you want to.

What I would rather talk about is how gathering data from players is useful to us. Because it is. Super useful! Without telemetry we would be resorting to guesses and risk only the most vocal minorities to be heard. For example, telemetry data is one of the major things we look at for deciding what nations to develop focus trees on. We get data on how popular difference choices are for focuses, letting us spot balance issues or unpopular paths that could use some love and care. We can spot if new out of sync errors are introduced in multiplayer in graphs and get crash reports automatically uploaded to help us fix problems easily. All this, combined with a scoopful of forum reading, is what helps us steer this ship, so thanks for helping :)

Oh I almost forgot, because we had to make the GDPR compliance hotfix we managed to sneak in a fix you guys have been asking for. We solved an issue for a case in China (similar things could also happen elsewhere) when a nation had both a takeover and inherited wars (like when seizing ownership in the Chinese power struggle) and was at the same time occupied. As a Japanese player this would lead to the less than happy situation of seeing your occupied areas flip back to the enemy and leaving troops cut off from supply. We also fixed a crash issue that was reported in some big mods. The patch should be releasing shortly.

Next week some of the team will be on summer vacation (including me!) but Bratyn is going to be here to talk about all the awesome stuff he has been doing with Britain, so don't forget to tune in!

  • Fuel for Thought
  • The Rise of Legal Pooch: GDPR always strike twice!
  • How we sell your personal data to Big Pharma for cocaine in 3 easy steps!
  • We have updated our fuel policy
  • Starved Baby Whales on the Teat is actually the name of the HoI 4 punk rock band playing at PDXCON 2019
  • Fuelling your conquests
  • Some of your data is belong to us, if you are okay with that
  • Help us help you help us
  • Our coders call it Nightmare Fuel actually
  • Adding fuel to the fire that engulfs the world
  • Anyone doing a dramatic reading of our privacy policy may request one Admiral to be added to the game
  • Proudly Introducing Gasoline Mana
 
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Hey, I was wondering if we might see a rework to how the AI uses Naval transport since this DLC is Navy focused? Any chance Italy wont lose its entire army to the Royal Navy and Japan will actually conquer Indonesia after Man the Guns? :p

Also since the USA will be one of the nations that get overhauled, will they get more factory slots? Historically, the USA had a 3x larger economy than the Soviet Union in WW2, while ingame they have less factory slots and thus the Soviet Union overtakes them lategame. (Source: https://www.reddit.com/r/AskHistori..._ww2_who_had_greater_industrial_capacity_the/)
 
Hey, I was wondering if we might see a rework to how the AI uses Naval transport since this DLC is Navy focused? Any chance Italy wont lose its entire army to the Royal Navy and Japan will actually conquer Indonesia after Man the Guns? :p
Podcat has said the AI will have the possibility to make naval "no-go zones", that should fix the problem of losing the transports (presumably transports will also have more opportunities to escape).

Also since the USA will be one of the nations that get overhauled, will they get more factory slots? Historically, the USA had a 3x larger economy than the Soviet Union in WW2, while ingame they have less factory slots and thus the Soviet Union overtakes them lategame. (Source: https://www.reddit.com/r/AskHistori..._ww2_who_had_greater_industrial_capacity_the/)
What we know is that the US industry will never be even close to historical, otherwise the Allies would win every game.
 
That's fairly straightforward: because it's not worth going through the complex process of fixing and testing on a part of the game that they probably have started to overhaul for the next expansion.

Also it's arguably not the worse of the bugs that are in the current version, and they have to draw the line somewhere. They fixed the Chinese Power Struggle instead, and that one could actually ruin a playthrough.

Yeah and they totally reworked air combat in the last major patch and look, an entire aspect of it is broken. I don't know what world you people live on where you think it's acceptable to ignore a game breaking bug for this long.

Because the mechanics of it are anything but obvious. The intricacies of air and naval interaction and that of land based versus carrier planes, is all quite elaborate. If it were an obvious fix then a hotfix would already have been released a month ago. I know a couple of modders who spent weeks working on it and have cobbled together a partial solution, but it is rough around the edges to say the least.

Yeah a couple modders working on it in their spare time have made more progress than an entire dev team. It wasn't broken before, why is it so hard to fix it now? How do you fudge something up this bad and then can't make a fix for it?

Not that it matters if this bug gets fixed in the update, i'm sure something else will completely break and all the new features will be implemented so horribly it'll be unplayable.

But that's okay because if you ignore whatever breaks and wait several months for the next $20.00 DLC, the game will work this time! They've assured us!
 
Actually this thread got me thinking about that (this is probably a topic for another thread though).

What if gold was a non-replenishable stockpile? Every nation would start with whatever stockpile they had in 1936. The only way to gain more would be conquest. This could then be spent on fuel, licenses, or equipment. It could maybe even spent some decisions, like boosting stability/war support.

The key would be that you can’t automatically gain more of it. There could be a small bonus associated with having a decently sized gold reserve, which you would lose if you spend it all. It would basically be a resource for emergencies or when you need a small boost.

This could alleviate political power, which is maybe getting a little overstretched as a game mechanic.


Interesting idea.

You could make gold replenishable with microtransactions, and thus HoI4 mobile would be born!

Edit: before disagreeing, you may want to contemplate the possibility that it was a joke ;)
 
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yeah all stats. a tank that cant move effectively cant really be where it needs to be etc.
I’m going to dispute that reasoning. During the Battle of Kursk the Red Army was unable to field all of their tanks and as such those without mobility were dug into makeshift bunkers as part of the defensive line. Therefore I would propose that a differentiation be made between the values as related to attacking a new province as compared to defending an existing one if possible. However that may rely on also calculating the tank battalion’s stats by using the entrenchment value of a division. In effect the tank could then be compared to some kind of anti-tank gun with additional hardness or defensive characteristics while its main armaments are unchanged.
 
I’m going to dispute that reasoning. During the Battle of Kursk the Red Army was unable to field all of their tanks and as such those without mobility were dug into makeshift bunkers as part of the defensive line. Therefore I would propose that a differentiation be made between the values as related to attacking a new province as compared to defending an existing one if possible. However that may rely on also calculating the tank battalion’s stats by using the entrenchment value of a division. In effect the tank could then be compared to some kind of anti-tank gun with additional hardness or defensive characteristics while its main armaments are unchanged.
That was such an off scenario, I feel like it'd be more fitting to be a general trait, which would decrease, to a degree, the lack of fuel penalty for entrenched armored units.
 
For some reason, I thought that a lot of the German recon was on motorcycles. Maybe I just watched the Great Escape too many times.
It is my understanding that most motorbikes in the German WW2 army where used by division level MP's, who had to be faster moving then everyone else in the division , so that they could set up and direct the divisional troops while they where moving, as it was standard practice to remove road sign posts while in retreat, or in the case of England because you expected invasion at any time.

I also had a 2nd idea about the new branch on the tank tech tree...It might be for tank transporters ,saving both fuel and losses from reliability issues in armoured divisions.
 
That was such an off scenario, I feel like it'd be more fitting to be a general trait, which would decrease, to a degree, the lack of fuel penalty for entrenched armored units.
While that may work it would be better implemented as part of a defensive doctrine change. That changes the speed value of armour battalions in exchange for increasing defence and leaving firepower the same. The tank is arguably better defended due to the (probable) presence of infantry anti-tank to either side while it’s rear armour is unlikely to be vulnerable to exposure as part of the line. And fuel doesn’t have an effect on the firepower of a tank save when related to a tank’s ability to outflank an opposing tank. Which in game mechanic terms would likely result in the piercing ability of the tank being most affected except in a situation where the tank is buried in the earth as opposed to a semi-trench as the gun would be lower down and thus make it easier to hit the lower glacis of an advancing tank which would increase the tank’s ability to pierce in that scenario. (The tactic was later used by the German while on the retreat.) On average however, assuming good coordination and tactics from the tanks in the division the piercing ability of the tanks would likely balance out. Hard attack would depend on the gun and the target angle but if in a line then a tank somewhere in the line will be able to get a side-shot at an opposing tank turret. They will also expose their own of course but then it becomes a numbers game. Overall however digging the tank into the ground increases its ability as compared to it merely being stationary.

Then you can put a load of bushes on it.
 
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Regarding reconnaissance: In order of descending likeliness assuming availability;
Aerial photography, already aquired maps, specialist infantry, regular infantry, local knowledge. This misses a few options but covers the major ones.

Outside of the various military intelligence circles photographic evidence was considered to be the next best thing to god handing you information as photographs were considered immutable. Presuming the army had maps from either friendlier times or previous conquests these would give a good overview of the upcoming terrain.

However it should be noted that outside of the United Kingdom’s Ordnance Survey few countries had an equivalent, France’s was disbanded in 1940 but kept the actual maps, some were in German hands while others were smuggled into the United Kingdom, including a complete map of France and Northern Africa. It’s geographical engineers became, infamous i suppose for their work on counterfeits. I could not find Germany’s or the USSR/Tsarist Russia’s equivalent but the Russian maps would likely be imprecise due to somewhat larger concerns. Such as disloyalty... Germany’s however would likely have been quite good. For those wondering the current German mapping agency was founded in 1999. It should be noted however that Soviet map-makers, at least after the war were exceptionally good at what they did. During the Cold War they secretly mapped the entire of the United States, Europe, Japan and other territories in exceptional detail.

Anyway, reconnaissance. Assuming the previous were either unavailable or outdated specialist infantry would be employed to advance ahead of the army and mark down various terrain features and potential obstacles. They would not go far, probably about a day or two ahead of the main force’s planned route but they would be able to tell what exactly to expect re: bridges, towns.etc

Local knowledge: most useful on the defence but it depends on the local attitudes. Polish people likely assisted the Red Army, for a time, while during the Allied invasion of Sicily locals could be asked where the Germans went and be trusted to give the true response the majority of the time. On a somewhat amusing note the Axis had no true high command coordinating shared logistics or similar unlike the Allied forces. The implementation of factions more closely resembles the Axis than the Allies in formation.
 
Is there a mechanism planned for supplying fleets? Like assigning convoys to fleets which can actually be sunk by submarines? Convoy requirements depend on home harbor - fleet distance. Oil is a very versatile resource. During production it represents making plastic parts like bakelite or similar stuff. Crude Oil can be turned into various fuels like diesel, heavy fuel for ships and light fuel for planes and cars. It can be turned into coke and hydrogen and sulfur can be extracted which in turn is versatile for fertilizers and rubber vulcanization. Technologies like cracking or reforming can raise the amount of fuel gained. Maybe one could address the refinery settings for toggling WHAT will be made from the crude oil. If you have limited resources, then this is crucial. I would like to see a comeback of currency as well to trade more efficiently. civilian factories serve for building stuff and can be assigned for producing export goods which will produce 'currency'. This you can trade for other stuff. Add gold and diamonds and cash crops like coffee, tea and cocoa as strategic resources and you gain provinces in the world, that will become more interesting for conquest and give some states means of trade. Also, I kinda miss food to supply armies so it might be a good idea to have agriculture in a certain way to supply vast armies - which are free currently. Just give out the arms and the soldiers will work the whole war...yeah, right. We are not touching civilian stuff like sieging here, but this could represent a kind of soft cap for armies like fuel is for tanks, planes and ships. Having no food will lead to combat penalties and attrition. So by encircling armies you really could starve them out. I like, where the game is going now. You won me back as a customer by now.
 
I like this, but I also hate that most of the things that are NEEDED to make this game good are in the DLC's (Germany and Japan being able to be made democratic for example), so I hope this DLC will not be another necessity to make this game that much better, I will never buy EU4 just because of the swarm of DLC, and I really hope this game does not end up like that game. I mean, to make this game the full expansion costs more then 80 euro's already. (40+20+15+10) That and WTT has not gone on sale yet once and is the most expensive, to look at the prices will Man the guns cost 25 Eur? Since it goes up with 5 Eur every DLC, I can't wait to get 40 Eur expansions...
 
The hoi team, what a keeper.
 
Meh...a AAA title is about 60€ alone. Add a single expansion and you are there already. I at least recognize the fact, that they keep the game developing and expanding. Asking for money in the process is not outrageous in my book. What kept me from starting in the beginning...well...the problem HoI4 had was that a full-fledged HoI3 existed with stellar mods like BI and TR. Starting anew from scratch with less functions but looking better...well try to convince the customer of it. 'Pay $$$ and you get less gameplay (which we will add later for more $$$) - but it looks nicer. Ask EA what this did for e.g. The Sims 4. But this game here is looking better every patch and can expect support.
And also keep in mind: there are some folk out there not wanting to buy a new rig to have make the sequel work if the current version is acceptable. And let us not forget, how many time one can spend on the game. HoI goes in the hundreds of hours usually - that is a meagre 80 cents for 1 hour of entertainment. 1,5 hours of cinema cost 8+ €. A single scoop of ice-cream might cost 1€ and is eaten in 5 minutes. It is relative. The greatest problem one might have is dish out all that money at once. Well, save money and buy part after part. One is not entitled to being able to purchase the game only because it exists.
 
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Apologies if this has already been suggested here(didn't want to read through 22 pages), but if PI want to add a new resource, can I suggest food?

Of course this opens up lots of new possibilities to restrict army size and impact war support etc. I don't see the point in adding additional scarce metals, such as copper, as this offers little over the existing resources we have.

As for the "fuel was too complex for the playerbase to understand" rationale for excluding it from the base game initially; well some people may be gullible enough to swallow that, but I think it far more likely that PI thought that they could deliver part of it as a paid option in a DLC later on.
 
Apologies if this has already been suggested here(didn't want to read through 22 pages), but if PI want to add a new resource, can I suggest food?

Of course this opens up lots of new possibilities to restrict army size and impact war support etc. I don't see the point in adding additional scarce metals, such as copper, as this offers little over the existing resources we have.

As for the "fuel was too complex for the playerbase to understand" rationale for excluding it from the base game initially; well some people may be gullible enough to swallow that, but I think it far more likely that PI thought that they could deliver part of it as a paid option in a DLC later on.
It was suggested multiple times from something like page 15 onwards
 
This has come back dozens of times already - anything close to proscribed topics is no go.

I went through the forum rules again and did not find anything about it. It was about using forbidden political symbols and keeping the civilians out of the game. Which is fair. But: they are working currently on a mechanism which introduces a kind of cap for armored units, ships and planes. We are talking about fuel. When raising and building a tank army now you will additionally have to think about sustaining them over time. I like the manufacturing mechanisms to produce equipment very much at the moment.

But there still is a simple problem: Armies not relying on fuel - which are for free after founding them. You just need the equipment and you are fine. So...if you have enough military factories, then you can churn out infantry divisions. Manpower is the limit. If you, however, produce a tank division, you will need a kind of upkeep in form of fuel to have them operating. I do not think, this is balanced well.

All 'living' components of an army need 'rations' - which are not depicted in the game. Let us not call it food for political correctness sake, but some stuff, men and horses need and which represents a soft cap on how many units of a certain type you can have operating. This will in fact, heavily influence the style of play for certain countries.
How to produce 'rations'? Well...this depends on the degree of agriculture in a country. We can have civilian factories, military ones - why not 'farms dedicated to military supply' or whatever we will call them. Those will produce said 'rations', which are consumed by units with living components. You can build more of them, some provinces are more fertile than others so they yield more than others and a agricultural tech tree can improve things even more. The point is, 'rations' are accessible for all countries so everyone with enough manpower can field an infantry-based army. Limits are manpower and ration production. Losing territory can have a severe effect on maintaining your army now. I cannot see, how this might clash with rules on topics. There are and have been games that used 'food' as a strategic resource for unit maintenance. I think it is o.k. to emulate the fact that you must have a certain degree of industrialization to create an army and a certain degree of agriculture to maintain it.
 
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