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HoI4 Dev Diary - Tech Changes

Hello, and welcome back to another Dev Diary for Man the Guns. Today, we will talk about some changes we have made to the tech and research system.

The biggest of which is, of course, the new tech tree for ships and other naval equipment. It is quite extensive, adding over 50 new technologies. Smaller changes and additions have been made to the armor and infantry tech trees through the addition of amphibious armor and to electro-mechanical engineering through the addition of Fire Control Systems.

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Many of these techs do unlock new modules, but some do not - ammunition techs, fire control methods and damage control training amongst other don’t, and instead provide passive bonuses. This makes them quite valuable as you don’t have to build or refit a ship to make use of them.

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The industry tree has also been expanded to accommodate fuel refining and storage. As one would expect, the new technologies improve the ratio of oil converted to fuel, giving you more fuel for the same amount of oil. The oil branch of the synthetic refinery tree no longer increases the oil output of each refinery but instead increases the amount of fuel generated by each synthetic refinery (synthetic refineries are not required to generate fuel if you have natural oil production!).

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Since this adds quite a bit of research to an already pretty full research tree, we have taken some steps to offset this increase.

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The first is that we have made a 15% increase to research speed across the board. The second is that a lot of the research in the new naval tech tree (as well as all the doctrine research) benefits from the research with XP system that gives you a fairly significant research boost if you have enough XP of that type to spare. For things like fire control methods and damage control training, researching without XP is significantly more time consuming to represent the lower effort spent during peacetime rather than learning from, well, experience.

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Lastly, we made some changes to how research bonuses are granted and how ahead of time bonuses are handled. Regular research bonuses are no longer reducing research cost but instead boosting research speed. A previous 50% reduction in cost is now a 100% boost in speed. Ahead of time bonuses have been changed to apply a flat reduction in years rather than a reduction to the penalty, so a 1944 tech with two years of reduction would be treated as a 1942 tech for the purpose of calculating research time.

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That is all for today. Next week, we will take a look at some of the art and music coming in Man the Guns.
 
How can you have more upgrades for mines than for subs?? that seems like a pathetic oversite
 
1936-1948 actually saw the adoption of high-pressure/temperature steam turbines in many navies (almost all navies started off the period with about 300-400 degree fahrenheit boilers, and ended a good deal higher, and Germany experimented (not entirely successfully) with some very high pressure units), and there was also the widespread introduction of welding in ship construction, as well as a shift from transverse to longitudinal framing - both pretty important steps in the evolution of propulsion and construction, respectively. These steps weren't exclusive to the 1936-48 period, but many key elements took place then. That said, I think they're proxied well enough by the hull techs - I'm just speaking up for the oft-forgotten longitudinal framing and high-pressure turbines :).

Thank you for informing us about the improved turbines and the framing changes - I knew nothing about these and will have to look out for them as I read more. I had forgotten about the introduction of welding and you're right, that's important (and presumably BlackICE will soon offer alternate riveting and welding techs so its players can choose!).
 
Sure, Midway could have been yet another draw, but the thing is that given the differences in industrial power and doctrine, a Midway-esque battle was inevitably going to happen sooner or later. Japan's ability to replace its ships wasn't getting any higher while the US just kept pumping out new ships. I don't mean to say that it would be easy; Japan probably could have carried on the war for significantly longer and it would be very expensive. But assuming no civil wars or things of that nature (which, let's be real: the US descending into a second civil war on the eve of WW2 is pretty "out there" alt-history), there is no version of the war where Japan actually wins.

Hence my position that for once, gameplay has to come before realism.

In terms of civil wars I was talking about the game rather than realism (as it's the game we're talking about) - I agree that an actual US civil war in the period was very unlikely (although a much more plausible outcome is a US that stays isolationist, and a Japan that doesn't attack the US but puts pressure on the UK/DEI/France instead - and in that situation the Allied fleets would find themselves stretched thin and not necessarily able to out-produce).

But the other thing to keep in mind is 'what does winning look like?' (@Secret Master , if there were royalties to be had from this phrase, I'd be transferring them to you later today ;)) The original contention (iirc - set me straight if I'm off) was "what's the point in building a navy as the Axis in the first place" (and didn't rule out ahistorical game paths (again, remember we're talking about the game, not history), which was why I included that in my original response. Besides the (potentially substantial) asymmetric benefits of commerce warfare, there's also the situation where a Germany and Japan hold off a US response until they dominate Eurasia (historically through Stalin agreeing to a separate peace early on, or in-game by the USSR being defeated outright) and the Middle East, at which point the Italian fleets can use the Suez Canal to back up the IJN, and the long-term production balance looks far more positive for the Axis. They may never (at least in any reasonable game length) have the capacity to invade the US, but they can comfortably consolidate control over Europe, Asia and Africa - which seems a pretty good 'win'.

Another thing to keep in mind is from Japan's perspective, without a navy there's no scope for offensive action outside of Korea and China, and as soon as a nation with a navy decides to put a stop to them, they'll be in all sorts of bother. So the question moves from "why should they build a navy" to "why should they start a war" - which in many ways reinforces the importance of having a navy - as without the navy for either Italy (to contest the Med) or Japan (to contest the Pacific), there's very limited scope for independent offensive action (in a historical-ish path).

Thank you for informing us about the improved turbines and the framing changes - I knew nothing about these and will have to look out for them as I read more. I had forgotten about the introduction of welding and you're right, that's important (and presumably BlackICE will soon offer alternate riveting and welding techs so its players can choose!).

You're very welcome :). It's not something that's written about a lot, at least outside of more technical books about warships. There were more advances after the war as well, with the initial developments in gas turbines (but I can't recall whether they'd be relevant to the time period - probably a bit late) and also advances in diesels which I forgot about prior to my last reply (which I'm very sketchy on, but think the diesels that powered some of Germany's cruisers, and Germany's plans to have diesel-powered battleships!) I'm also not sure how far along battery technology (for subs) came on during the period.
 
How viable is it still to rush 1944 techs? Sounds like it's still going to be doable around 1940-41, especially with the new +15% research speed buff that will buff hyperspecialising minors, that in multiplayer focus only on one or two things. Granted, it's an improvement to the current state of the game where both teams can easily get them in 1937-38 if there are no house rules against it, but I'd still rather not see P-51 Mustangs in the Battle of Britain. Unless there's going to be a server rule that restricts ahead of time research, it looks to me that our long lists of house rules in vanilla HoI4 aren't going anywhere.

Not very. The old tech rushing methods were designed to abuse stacking research bonuses. -10% from designer, -15% from free trade, and -50% from a technology bonus resulted in a whopping -75% to technology cost for a particular technology, and those are the bonuses any country can get, not counting country unique bonuses like national spirits or the research bonus from computing technology. This is why technology bonuses were so broken to begin with.

All the cost reductions are instead being turned into speed bonuses. So, the above bonuses would now be +150% research speed boost. To do maths. If a technology takes 1,000 days to research (which is rather common for extreme ahead of time shenanigans), under the old system the above bonuses would knock that down to 250. Under the new system, it would be knocked down to 400.

1,000 x 0.25 (75% reduction) vs 1,000 / 2.5 (+150% research speed boost)

Tech rushing is still doable, but it would be a much bigger sacrifice for the country in question (having your tech slot occupied for 400 days is pretty bad), and take a lot longer to bring technology rushed equipment to the field. 1944 equipment in 1940 will not be possible anymore.

I do expect technology rushing to stay a thing, but instead it will be 1940 equipment that is rushed instead of 1944.
 
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Well, extension of tech tree looks promising, but the more parts of naval/land/air tech we will get, the more actual getting general rework of research becomes. Maybe, something like HOI3 - with every sphere, slowly developing on it's own, while you decide, what will be the focus.
 
I don't see Israel as having a different doctrine than any listed in game. It's just a nation with mobile warfare, full planning bonuses, and a healthy tech advantage. Not sure what you see in them that you think isn't represented by that, or what doctrines you are seeing that aren't represented. Can you give a little more clarification on what you want this doctrine to be? Not just examples, but the actual idea or driving principles that make that doctrine, a doctrine?

Mobile Warfare/Superior Firepower/Grand Battleplan/Mass Assault are mainly focused on opeational level, tactical level doctrines are missing now in the game.

IMO we should have different tabs for tactical, opeational and strategic doctrines.
 
They still have to research some technology to improve the amount of fuel they get from their natural oil. And while they doesn't need it in your regular game since you can trade with the allies, having synthetic rubber production doesn't hurt the Soviets.

Yeah but that's like 2-3% more research for a 15% bonus, still a huge difference.

Also, soviet Union has a bad start with tech and would not out tech ze germans, but historical SU was on par with German Tech w/o the Wunderwaffen.

I wouldn't mind bumping the Soviet tech a bit, but it has to be nerfed in other areas then to maintain the balance. Just feels like with this tech and the other advantages that the have, ze Germans would't really stand much of a chance against them without a player interference.
 
Tech rushing is still doable, but it would be a much bigger sacrifice for the country in question (having your tech slot occupied for 400 days is pretty bad), and take a lot longer to bring technology rushed equipment to the field. 1944 equipment in 1940 will not be possible anymore.

That's completely fine for minors like Hungary, who are the Axis air controller in vanilla MP. They might get a couple of industry techs a little later, but that's trivial compared to getting FTR 3s in 1940.

Btw the current meta is for both sides to have FTR 2s in 1937, since FTR 3s are always banned till the late-game. If your calculations are correct, we'll still see FTR 2s around 1938 in MtG. Disappointing, but not surprising.

(although a much more plausible outcome is a US that stays isolationist, and a Japan that doesn't attack the US but puts pressure on the UK/DEI/France instead - and in that situation the Allied fleets would find themselves stretched thin and not necessarily able to out-produce).

While more plausible than a civil war, I don't see America staying out of the war as realistic. By 1941 the US was already one foot in the war on the Allied side and FDR had arguably been seeking to provoke an incident with Japan for years. By the time of Pearl Harbor Congress had become increasingly pro-war and probably would've flipped to majority pro-war in 1942, even without PH.

I also don't see the US sitting idly by as Japan pillages the oil- and rubber-rich East Indies.

US entry was unavoidable and Japan's best course of action would have been not to mess with the West.

at which point the Italian fleets can use the Suez Canal to back up the IJN

The Italians risking their navy to help the Japanese sounds a bit far-fetched. The Axis was a pretty dysfunctional bunch when it came to co-operating with allies, and the co-operation between the European and Asian Axis was pretty much limited to signing the same piece of paper.
 
I wouldn't mind bumping the Soviet tech a bit, but it has to be nerfed in other areas then to maintain the balance. Just feels like with this tech and the other advantages that the have, ze Germans would't really stand much of a chance against them without a player interference.

I think that in a historical focuses game, I would want the German ai to lose to the soviet ai.
And a low tier Player like me can beat the soviets, so they can use a buff.

I see it like this: soviet Research mirrors German Research without navy, you want Tanks, Fighters, CAS, TAC, artillery, industry, land/air doctrines.

But you have no air doctrine, you take until 38/39 for the 5th Research slot, I fail to see an untoward buff for the soviets.