Hearts of Iron IV - Development Diary 2 - The Tools of War

[podcat]

Welcome to the second development diary for Hearts of Iron IV! Today, I am going dive right into the meaty stuff and present one of the larger changes we've made to the game - equipment. It's a broad topic with many implications for how the rest of the game is played, so my goal is to present the general idea without digging into all the details just yet. But don't worry, there will be more details than you can shake a field-marshal's baton at in future diaries!

Production
We wanted a more interesting industry model that offered a compelling reason not to always use the latest technology, as well as adding more unit flavor in HoI4. To accomplish this we developed a model where you no longer build full divisions and aircraft wings one at a time; instead, you create production lines to pump out individual vehicles. The longer you run a single production line the more efficient it gets at producing that piece of equipment, and the choice of when to switch over to, say, a newer tank model becomes tricky. Is the war effort best served by a shiny new Tiger that can outclass the competition, or would you rather have 20 Panzer IVs? You will have to make choices like this. Upgrading your equipment now means replacing your old models at the front with new tank designs, for example. The old ones can be put in reserve, sent to less important places, or perhaps given as aid to an ally.

This means that a division is basically an assortment of different equipment combined with men who operate them. Most of the stats of a division will come from equipment, so a panzer division without tanks will not be particularly fit for duty. As for exactly what equipment is used by each division, it will depend on how you have structured your divisions. At the smallest level, we are looking at battalion types that make up your divisions determining how much you need of everything, but a division is still the smallest unit that can be moved around the map. For example, adding an extra battalion of artillery to a division means that it will now also require a few more men and a specific number of artillery cannons that you will need to produce before that battalion will be effective. We’ll talk more about this in a later diary.

Technology
Equipment appears all through the new technology trees. The idea is that unlocking a new piece of equipment should be very visible, and it should be very clear what you will get. Here is a screenshot showing what the armored tech tree looks like for Germany:

Armored technology is based around chassis that you unlock. Each of the chassis has 4 subtechs, each of which unlocks a variant. So, for example, once you have unlocked the Panzer III tank you can research the tank destroyer variant, StuG III. The StuG III was a Panzer III chassis with the turret removed and a larger fixed gun placed in its stead. Variants like this can be switched to production lines from the original chassis without much of penalty, so once the Panzer IV becomes your main tank and the Panzer III no longer measures up, it's a perfect time to convert to producing StuGs on those Panzer III lines. Most nations developed their vehicles like this during the war, and we wanted to include this flavor. Historically, the StuG III ended up being the most produced armored vehicle in Germany during the war.

There will also be ways to create more custom equipment variants with abilities unlocked by experience over the course of the war. This is also something we will go into more detail on in the future.

By switching to equipment from HoI3's more abstracted model, we gain a lot of cool flavor as well as introducing many of the actual interesting choices that leaders of the time had to deal with. We also believe it will make it easier to understand for new players, as well as being more immersive for players. You will now see results like "10 heavy tanks destroyed" rather than some abstracted strength percentage. Because the production models changes over to lines it also doesn't introduce any more unnecessary micro management, so it is really a win-win.

That's all from me for today, see you again in a month for another diary!

+ Bonus read: Hearts of Iron IV: How we changed the world
Time to flex your strategic muscles and test your might as your ability to lead your nation will be the ultimate weapon in your arsenal in Hearts of Iron IV.
On the battlefields, in the factories, and at the negotiating table. Victory at all costs.
Here are a few of the women from the World War II era and how they changed the world:
https://forum.paradoxplaza.com/foru...s-of-iron-iv-how-we-changed-the-world.760924/

 

[Darkrenown]

Release version will have more lens flare.

 

[podcat]

I'm assuming the four little icons next to the tank picture are upgrades?

"Each of the chassis has 4 subtechs, each of which unlocks a variant."

 

[Darkrenown]

Cool stuff!

My only concern is what this means for minor nations. Doesn't this mean you have to make up fictive tech trees for 50+ minors just in case someone wants to play as them and develop their own domestic tanks?

Nope, worst case they have "Basic/Improved/Advanced Medium tank" etc.

 

[Darkrenown]

The explanation sounds exciting although the screen shot makes it look a bit poultry. I'm wondering how the production lines will work in practice. Can you choose to have several tank types produced at once? Will this mean that there is a production efficiency malus if you do?

Tanks will not be chickens, don't worry You can make as many production lines as you like, but each factory can only be assigned to one line at a time, so if you spread your efforts too thin you will not be making much of anything. We'll go into more details about production in a future DD, this one is just the basics to show where we are heading.

 

[Darkrenown]

i like the tech tree as its very clear and easy to follow. Im interested in how the different tech trees will look as some nations didnt produce certain types of equipment. Like is the Super Heavy tank gone, Maus is listed as only a heavy tank.
I guess the reason for putting pzIV at 41 is to have a more continues tree, while having pzI and pzII as mediums instead of light tanks like they should would be to make the medium armored divisions upgrade properly. Only having E-50 as 1945 with no E-75 is a bit confusing imho but i guess its letting the trees evolve into a MBT design in 1945 which should make it easier to balance the nations.
So three questions:
Is the Super Heavy tank brigade gone?
Are we going to see roughly equivalent tech trees or can they diverge between the nations. Like Japan never really produced a heavy tank but had blueprint on the super heavy O-I and produced 1? testing tank.
and the most important question: will we be able to produce the TOG II as britain?

Super heavies are still around, the tree perhaps isn't clear enough, but the Maus is out to the side there in its own class (and the Pz I and II are actually light tanks, despite the heading. Alpha UI.). Nations are all going to have the same basic models available so Japan can build an O I if it really wants to. And no TOG II, sadly, our rule for early heavy tanks is that need to be multi-turreted where possible so TOG is too sensible as odd as that sounds.

You're also correct that the E-50 fills the MBT role here, and that the PzIV as a later tech makes the tree flow better. It was also around the time it got its long gun and became a clear upgrade from the III.

 

[podcat]

It sounds great on paper, but the tech screen really look simplistic to represent armoured development.

I'm sorry. We will try to create messier, hard to understand interfaces in the future instead

Edit: also why the ridiculous concept of super heavy tanks?

Because they were things that people built?

Also it should be E-25 to replace Stugs and jagdpanzer.
E-50 to replace Pzkpf IV/V
E-75 and E-90 to replace VI

The role we are using here is that of main battle tank, which for Germany the E-50 fits best (its a bit early, but since it was never actually built it gives some freedom). For the US this is the Patton and for USSR a t-54 for example.

Nice. Since divisions are made up of equipment, will it be possible to capture and integrate foreign equipment after a battle or after defeating a country?

We havent gotten to that in development yet, but the idea is to make this possible.

 

[Darkrenown]

Looking at the backgrounds PZ1 appears to be researched and in production, PZ 2 being researched and Tiger unlocked but not researched yet, something along those lines?

Yup!

 

[Darkrenown]

I like what I see and hear!

What would the dotted line between Tiger and PzIV represent, you have to have them both to unlock the other?

It means it's a linked tech, if you have one you research the other cheaper, and it provides a way to "cross over" if you have researched down one line. Not entirely sure we'll keep the Improved medium <-> Improved heavy link at this point, but it's used it several other places too.

 

[Darkrenown]

Darkrenown - so this represents the PZ IVf2? Makes sense.

Exactly. Although, warning upfront, we will likely not follow the variant naming schemes of the various nations exactly.

can we buy equipment?

Yes.

One thing that stuck out to me immediately - can we have Light - Medium - Heavy - Superheavy from left to right (basically mirror the current image)? I think that would make the overview even more readable (strongest tanks on the right). Just a suggestion!

Good point!

 

[Darkrenown]

The tech tree looks very simplistic, like for a console game.
Everything except the actualiteit picture of the tech tree sounds fantastic. I do hope that this is moddable and also means that we finally have nation specific equipment.

PzKpf III should have at least 4 variants. 3.7cm, 5cm L/42, 5cm L/60 and finally when the PzKpfw IV from Ausf F2 is in production the option to equip the Pzkpfw III with the 7.5cm L/24.

We just unlock the 1 model via the tech and you'll be able to upgrade the gun/engine etc via practical experience.

Also the StuG III should only become a Td from the Ausf F.

There's no reason they couldn't have done so earlier, it's just a decision to have a fixed gun over a turret.

PzKpfw IV -> StuG IV?
Pzkpfw V -> Jagdpanther?
Pzkpwf VI -> Ferdinand/Elefant?
PzKpfw VI Ausf b -> Jagdtiger?

Mostly. I went with the JagdpanzerIV over the StuG IV though IIRC.

Also it should be E-25 to replace Stugs and jagdpanzer.
E-50 to replace Pzkpf IV/V
E-75 and E-90 to replace VI

I'm not sure why you want us to remove the historically produced tanks for some planned and never built models? Where possible I use stuff that was actually built.

 

[podcat]

Are we gonna be able to upgrade specific equipment parts like in HoI3, or is each unit preset and based only on Chassis tech?

Either way, I will be pre-purchasing this with the force of a thousand suns.

Only chassis, although there may be the option of "melting down" equipment to feed the production of compatible variants.

So we are limited to historical designs only? I hoped for more freedom in tank design department. Still, it's an improvement over what was before. The picture is quite clear in itself, but the armor screen ain't covering StuG III that's described in DD itself. Will it be added later on (and made "transparent") or will it be "visible" only after Panzer III's chasis is developed? What I mean is that wouldn't it be a bit counter-intuitive in terms of what the player wants to develop? I'd love StuG III as an infantry support but if I couldn't be able to see it wouldn't I have to search for it blindly or be forced to ask how to develop it? Maybe I messed something up, but I want to claryfy this one bit.

"There will also be ways to create more custom equipment variants with abilities unlocked by experience over the course of the war. This is also something we will go into more detail on in the future."

The StuG there is represented by one of the buttons on the Panzer III tech (the one that looks like a bullet striking armor). We only have pictures of the main chassi at the moment, variants are indicated by those icons/buttons.

I think you guys are kind of missing the fact that the model names are just flavor descriptors for "Improved Medium Tank" and "Early Light Tank" and stuff. It's not trying to be a realistic Armour Development Simulator.

yeah, its flavor names for different levels of armor. If the player wants differences they need to be spending experience acquired in the war on variant development.

 

[Darkrenown]

So I can buy 3000 Tanks for Estonia and then invade latvia?
also if we produce trucks are forces getting supplies faster?

Well, if you can afford them, and find someone willing to sell them, and you can man them, sure. The USSR might react with alarm though.

Trucks/Horses won't be tracked though, they are assumed to be part of the basic equipment of a division.

 

[Darkrenown]

That's what the four icons to the right of each tech are. I'm guessing TD, SpArt, SPAA (based on the plane), and something else.

SP rocket arty is the 4th. Bit less common and not quite as good a fit, I know, but close enough.

 

[Darkrenown]

Makes sense. Its sad about the TOG II because its such an iconic "silly" tank that it would make me want to play britain just to field them. From a design perspective i can see why there are better tanks. I would imagine Churchill and Black Prince as Heavy tanks (would fit the 1941 and 1943) then Tortoise as the Super Heavy (1944) design and Centurion as the MBT.

You are pretty spot on, but the UK basic heavy tank is the Vickers Independent That is what I meant by the ToG2 being oddly too sensible, we want basic heavy tanks to be the pre-war multi-gunned wonders.

 

[Darkrenown]

In my opinion the Maus should be a 1945 model coming after the Tiger II and the E-50 a continuation of the Panther.

Nah, the Maus is an entirely different branch for a different role, not a direct upgrade of the KT. The E-50 is a continuation of the Panther here though.

 

[Darkrenown]

Yes, but that is the major problem for Germany. The E-50 was not build either. Than we should look first at the PzKpfw V Ausf F1 (Schmalturm turret) and F2, before we look at the E-50. As those were closer to be finalized than the E-50.

It's true they were closer to being made, but I didn't think it was enough of an upgrade for the next model of tank, especially not if we make the leap to MBT. Nazi Germany obviously wasn't around for the first generation of post-war tanks, and the Leopard is too far into the future, so I figured the E-50 was the best of the bunch.

 

[Guraan]

How moddable is this?

Very.

Can you change the amount subcategories?

Yes.

Does every model have to have the same amount of subcategories?

The number of subtechs is individual of each tech.

Can you post an example of what a tech looks like in the game files?

improved_light_tank = {
	enable_equipments = {
		light_tank_equipment_2 
	}
		
	path = {
		leads_to_tech = advanced_light_tank
		research_cost_coeff = 1
	}
		
	path = {
		leads_to_tech = basic_medium_tank
		research_cost_coeff = 1
	}
		
	research_cost = 180
	start_year = 1938
		
	folder = {
		name = armour_folder
		position = { x = 4 y = 4 }
	}
		
	sub_technologies = {
		improved_light_td
		improved_light_art
		improved_light_spra
		improved_light_spaa
	}
}
	
improved_light_td = {

	enable_equipments = {
		light_tank_destroyer_equipment_2
	}
	
	research_cost = 180
	start_year = 1930
}

 

[Darkrenown]

Trucks not? Is there a distinction between motorized/regular inf brigade? What about APC's?

MOT needs more "equipment", Mech has it's own more expensive equipment representing APCs.

 

[Darkrenown]

So you're saying there is a generic thing, called "equipment," that one must manufacture?

Yes, you don't build absolutely everything individually. We'll say more when we do the detailed production DD.