HoI4 Dev Diary - Tech Changes

[Archangel85]

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.

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.

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!).

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

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.

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.

That is all for today. Next week, we will take a look at some of the art and music coming in Man the Guns.

 

[Archangel85]

What's the symbol in the corner of the 36 heavy hull? Maybe a special variant? Coastal Defense or Super Heavy ships?

Super Heavy Battleship.

 

[Archangel85]

Why dont you add the mechanic to Lend lease ships? That would make a lot of sense, even historically.

Ships work fundamentally different from other equipment. Lend Lease for all other equipment just moves stuff in the stockpile around from one country to the other. Lend Leasing ships (except convoys, which also exist in the stockpile) would require us to transfer actual units that are already on the map, and is a bit more complex (you need to select that specific ship, they need to have the manpower to man it, they need to have a naval base in range etc.). It is definitely doable, but it is not a trivial effort.

 

[Archangel85]

Now, the question is: are gun calibers and armour thickness in inches, centimetres, or (oh my god why) millimetres?

Depends on the country. The different tech levels not necessarily represent gun calibers across all countries (so there is no "15 inch guns" tech, just a Heavy Battery I tech) to simulate stuff like rate of fire, number of barrels per turret etc. It would probably be possible to mod the system to work more like that though.

Will any changes to aircraft tech be made? If not now what about the future?

No changes to air tech right now, but it will probably be looked at in a future DLC.

 

[Archangel85]

Question for modders: does the updated research bonus method still use the same code as the old one or will all custom research/ahead of time bonuses have to be updated?

you'll have to update them, but a mass search and replace should work fine.

Also, will previously coded bonuses for, for example, Battleships still work for Heavy Ship hulls?

Yes, the techs are scripted to be backwards compatible. bc_tech and bb_tech will give bonuses to heavy hull research and heavy armor schemes, ca_tech and cl_tech do the same for cruiser techs etc.

How will it work? Is it just one super heavy hull, for 1936, or once unlocked it becomes a variant for all BB hulls?

In other words, I can build the Yamato off the 1936 BB hull, but how do I build Design A-150?

Just one SHBB hull. Guess you'll have to update the engines?

In one of the previous dev diary's it was said that we would be able to choose and refit ships with different engines but i don't see anything in the tech tree that looks like it it represents engines. Have different engines been removed or are they unlocked by researching new hulls?

Engines are unlocked by hull techs. We felt that there wasn't enough to make separate engine techs interesting.

 

[Archangel85]

How does the experience bonus work? Is it just for the tech you're researching right now? So if you press the button after you've already researched half of a tech, does that means you've effectively wasted a bunch of experience than if you had hit it much earlier?

You have two buttons: regular research and research with XP.