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HOI4 Dev Diary - Naval Terrain

Today we are going to talk about Naval Terrain and start talking about some of the core changes to the naval game.

We felt that we wanted to make where you fight more important, and where possible give advantages to people fighting in home waters. The sea in HOI4 has previously generally been either “ocean” or “ocean in range of enemy land based aircraft”, and otherwise mattered little. That’s about to change!

To do this we are introducing several terrain types for seas. These impact what ships work best there, how mines function as well as some other stuff. In total seas are divided into 4 types:
ocean.jpg

Regular Ocean has no special effects, so its similar to plains on land.

Screenshot_4.jpg

Fjords & Archipelagos come with some hefty penalties to big ships, but make it easier to hide (all numbers still quite work in progress btw!)

Screenshot_3.jpg

Deep Oceans on the other hand are not good for light ships. They are also not good place to mine due to their depth and vastness. Subs like this area (mid atlantic gap = bae) because it is also easier to hide here.

Screenshot_5.jpg

Shallow seas are a bit harder to maneuver well in, and not a great place for submarines.

There is also some possible modifiers on them:

Screenshot_6.jpg

Arctic Water is a general bad area to operate in, wearing your ships down and causing potential accidents. It also increases casualties if ships sink for any reason. This modifier works much like Extreme Cold on land so it depends on the time of year and temperature.

Screenshot_7.jpg

Some places in the world have quite a lot of sharks and there are a lot of stories of heavy casualties after the sinking of ships due to sharks. The USS Indianapolis is a famous example where due to several reasons, sharks among those, something like 75% of the crew were lost. It is honestly mostly a cool flavor thing though we wanted to have in ;)

Your performance in these are also affected by Admiral Traits. As we have shown a bit before your Admirals can now gain traits for different terrain types.

Screenshot_2.jpg

  • Cold Water Expert reduces the impact of arctic waters
  • Inshore Fighter gives combat bonuses and speed when operating in Fjords and Archipelagos
  • Blue Water Expert gives combat bonuses and speed when operating in deep oceans
  • Green Water Expert gives combat bonuses and speed when operating in shallow seas
You might have noticed some strange colors in the screenshots above. We are adding some more mapmodes, but it’s mostly all pink and full of coder art at the moment, so you are going to have to wait a bit more to see all those. I am pointing it out because I need to show the terrain mapmode a bit to more easily show off the naval terrain across the world
Screenshot_8.jpg


Around the Dutch East Indies several of the terrain types are visible (the colors on land in this mapmode are still in need of some tweaking btw). The brightest there is archipelagos with the other shades of blue being shallow seas and regular ocean and the darker areas is deep oceans.

This is what the Atlantic and Europe looks like:
Screenshot_9.jpg


Notice the deep ocean in the Atlantic and the fjords around scandinavia.


That’s it for this today, next week we are going to start going over some of the more core naval changes. Seeya then!

Rejected Titles:
  • Naval “terrain” is an oxymoron, like “Military Intelligence”
  • SHARKS
  • Fjords, or how to make Scandinavia relevant this DLC
  • Not from the creators of Sharknado, comes SharkBlizzard
  • Podcat read a book about how horrible it was being on a destroyer in the arctic
 
Will you be able to send your trade convoys through a certain route, avoiding dangerous seas? I mean, naval invasions and military divisions on sea are sort of easy to maneuver, but trade convoys would be nice to tell them what route to take, according safe seas.
yes.
 
Today we are going to talk about Naval Terrain and start talking about some of the core changes to the naval game.

We felt that we wanted to make where you fight more important, and where possible give advantages to people fighting in home waters. The sea in HOI4 has previously generally been either “ocean” or “ocean in range of enemy land based aircraft”, and otherwise mattered little. That’s about to change!

To do this we are introducing several terrain types for seas. These impact what ships work best there, how mines function as well as some other stuff. In total seas are divided into 4 types:
View attachment 410010
Regular Ocean has no special effects, so its similar to plains on land.

View attachment 410005
Fjords & Archipelagos come with some hefty penalties to big ships, but make it easier to hide (all numbers still quite work in progress btw!)

View attachment 410007
Deep Oceans on the other hand are not good for light ships. They are also not good place to mine due to their depth and vastness. Subs like this area (mid atlantic gap = bae) because it is also easier to hide here.

View attachment 410008
Shallow seas are a bit harder to maneuver well in, and not a great place for submarines.

There is also some possible modifiers on them:

View attachment 410004
Arctic Water is a general bad area to operate in, wearing your ships down and causing potential accidents. It also increases casualties if ships sink for any reason. This modifier works much like Extreme Cold on land so it depends on the time of year and temperature.

View attachment 410006
Some places in the world have quite a lot of sharks and there are a lot of stories of heavy casualties after the sinking of ships due to sharks. The USS Indianapolis is a famous example where due to several reasons, sharks among those, something like 75% of the crew were lost. It is honestly mostly a cool flavor thing though we wanted to have in ;)

Your performance in these are also affected by Admiral Traits. As we have shown a bit before your Admirals can now gain traits for different terrain types.

View attachment 410003
  • Cold Water Expert reduces the impact of arctic waters
  • Inshore Fighter gives combat bonuses and speed when operating in Fjords and Archipelagos
  • Blue Water Expert gives combat bonuses and speed when operating in deep oceans
  • Green Water Expert gives combat bonuses and speed when operating in shallow seas
You might have noticed some strange colors in the screenshots above. We are adding some more mapmodes, but it’s mostly all pink and full of coder art at the moment, so you are going to have to wait a bit more to see all those. I am pointing it out because I need to show the terrain mapmode a bit to more easily show off the naval terrain across the world
View attachment 410009

Around the Dutch East Indies several of the terrain types are visible (the colors on land in this mapmode are still in need of some tweaking btw). The brightest there is archipelagos with the other shades of blue being shallow seas and regular ocean and the darker areas is deep oceans.

This is what the Atlantic and Europe looks like:
View attachment 410013

Notice the deep ocean in the Atlantic and the fjords around scandinavia.


That’s it for this today, next week we are going to start going over some of the more core naval changes. Seeya then!

Rejected Titles:
  • Naval “terrain” is an oxymoron, like “Military Intelligence”
  • SHARKS
  • Fjords, or how to make Scandinavia relevant this DLC
  • Not from the creators of Sharknado, comes SharkBlizzard
  • Podcat read a book about how horrible it was being on a destroyer in the arctic
ok now THIS is epic. When are y'all adding a turkey, scandi, or South America DLC
 
It's obvious you've never been to sea then. Small boats don't do well in the rough seas that are common in deeper waters. In calm waters, sure no problem, but wait until that ship with a 2 foot freeboard gets into a sea state of 3. All hell would break loose. Just look at the USS Wasmuth (DD-338), A Clemson class DD that was sunk because a storm caused two depth charges to explode.

Even larger ships could have a hard time while in storms on the high seas. A good example would be the USS Pittsburgh (CA-72) in this video. I'll grant you 100 foot waves and 70 kts winds arn't common, but a smaller ship would have floundered and sunk like the Edmund Fitzgerald on lake Superior
I have never been in the deep ocean, no. But I also said that the penalty should be linked to weather rather than terrain; as you said there is no problem in calm weather.
 
I have never been in the deep ocean, no. But I also said that the penalty should be linked to weather rather than terrain; as you said there is no problem in calm weather.

But no Admiral would send out ships hoping it would be nice weather. The penalty sort of makes sense if you think of it as spending a lot more time routing the ship round bad weather, staying closer to shore where possible and basically doing everything possible to avoid bad situations.

And then weather penalties on top for when they get it wrong.

(this was in the days before constant weather satellites. You basically asked the weathermen to read the tea leaves and hoped for the best. I can see them being very careful of the escort ships they sent out in those conditions.)
 
Soviet/Commie Rework and DLC is most likely next. WTT was a Fascist update and MTG is obviously Democratic. So next one in that case is most likely Commie. The theme would be hard to guess.

Might be SCW/Exporting Communism (So, Soviet Union gets a new focus tree, as does Nat/Rep Spain).
 
In today's stream, I saw that you can have McArthur as the leader.

Amusingly enough, in the China national focus tree, it's possible to get McArthur via the Chinese Expeditionary Force focus. Would this whole thing still be possible if that happens? Or would McArthur exist both as a FM for China and leader for the US?
 
In today's stream, I saw that you can have McArthur as the leader.
This has always been the case, though. He's a Republican candidate in - I think - 1944.
 
Can someone help me, what does it mean in real life to be a "cold water expert" for an admiral? How could an admiral mitigate the effects of the weather without just...leaving it? Maybe Paradox just wants a modifier for each thing, but I don't know of any way that an admiral, by using their own skill, could affect that. Seems odd to me, I would say just drop that modifier and cold weather is just something you have to deal with. Is there warm weather as well, or I take it this does this not matter as much? I know the cold had a big effect on the steel originally used by the USA (it dropped below the point where it became very brittle) and the warm does not do that, but I don't have all the facts in front of me - there could be more disease or something after all.

I assume this will be fully moddable? More terrains, more modifiers, whatever we like?

Can terrain be combined? For example, can you have a shallow water fjord, or arctic deep ocean?
Certainly. There is a certain maintenence aspect to boating in icy waters. When the waves splash the ship in below zero degrees some of the water ends up freezing unto the hull, this ice build up needs to be knocked of every so often or it will debalance the ship and you will overturn.
Assume the admiral is not alone but comes with a command structure equally experienced in the terrain, and crews drilled in these measures.
 
Good news all around.

Mind you, in the Baltic sea, the coastal heavy ships of Norway, Sweden and Finland should be formidable obstacles for any of the Allied, Soviet or German navies.

There is a reason they resisted invasion of Sweden and that is because navigation of heavier ships like battleships aren't suitable in the Baltic due to limited and predictable pathways available to ships without a shallow draft.

It would be great if that was reflected. I am not sure placing this as "fjords", it's probably its own type of water terrain, perfect for submarines (impossible to detect as evidenced by a couple of decades of submarine hunting in Sweden post-WWII) etc. This is probably the same as the Aegean and Adriatic sea and maybe Malacca straights?

If you do, then please sort out the AI. If I ever see battleships or Carriers in the Baltic, we will know you totally failed on this one.

And this of course creates quite a dimension to the British Empires possibility to twart any fascist movements in Baltic sea states, because at war they probably couldn't execute a naval invasion without serious loss of small to midsize ships in Skagerak and Kattegatt.
 
Mind you, in the Baltic sea, the coastal heavy ships of Norway, Sweden and Finland should be formidable obstacles for any of the Allied, Soviet or German navies.

There's definitely the potential for this, but keep in mind the actual performance of the Norwegian heavies during Weserebung.

Historically, in WW1 (when Denmark remained neutral), Britain used submarines to good effect in the Baltic. In WW2, Germany heavily mined (and supported these with coastal fortifications and air patrols) the straits through Denmark to the Baltic to keep subs (and other ships, but other ships would have been at the mercy of air power) out.
 
There's definitely the potential for this, but keep in mind the actual performance of the Norwegian heavies during Weserebung.

Historically, in WW1 (when Denmark remained neutral), Britain used submarines to good effect in the Baltic. In WW2, Germany heavily mined (and supported these with coastal fortifications and air patrols) the straits through Denmark to the Baltic to keep subs (and other ships, but other ships would have been at the mercy of air power) out.

The Norwegian coastal defence ships that were sunk were very old, constructed in 1899, compared to the fairly modern Finnish Väinämöinen and Swedish Sverige class ships.
 
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Maybe some focus tree for Greece? :eek:
Greece, Turkey and Bulgaria (maybe even Albania if they gave the Czechs a tree). Will prob get their own focus tree in a "Southern Balkan Expansion". They have similar circumstances. The three of them (Turkey, Greece and Bulgaria) all can rebuild their former Empires. Turkey could rebuild the Ottoman Empire, Greece could rebuild the Byzantines and Bulgaria historically sided with Germany to restore the Empire that they lost after WW1.
 
The Norwegian coastal defence ships that were sunk were very old, constructed in 1899, compared to the fairly modern Finnish Väinämöinen and Swedish Sverige class ships.

Oh aye - I only said that because Frozen Imperator specifically mentioned the Norwegian coastal defence ships, although it's worth keeping in mind Soviet air attacks did give Väinämöinen some trouble during the war as well. The coastal BBs were good against enemy ships, but their slow speed made them potentially vulnerable to airpower.