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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
 
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

Please give some thought to the difference between restricted waters and shallow waters.

All the restricted waters, not just the English channel, should have stacking penalties on capital ships. This should be independent of whether the sea area is shallow or not. If you are fighting for naval superiority in restricted waters then you should want to leave your battleships behind or bring just a limited number, but bring all the destroyers and cruisers you can get. The question of whether you should also bring submarines should be independent of this.

HoI games always have had ridiculous stuff happen in the English channel like U-boat sinking entire fleets of surface warships, or battleship fleets duking it out in confined waters where they (the fleets) don't actually have even enough space to turn around at combat speed, and the effects of small craft (which would realistically be a serious danger to large ships in the channel) aren't modeled in any way.

You have north sea and channel exactly the same territory. With effects on submarines only. While that is welcome, it's not enough to make naval warfare in that area really realistic. The channel was not a good area for battleships because of the narrow width allowing all kinds of small craft like torpedo boats to quickly sortie from minor ports, and because the channel just wasn't wide enough to allow for good maneuvering of the kind of larger flotillas that battleship combat would involve... The North area on the other hand had quite a lot more space to maneuver although of course the shallowness was just as bad, even worse, than in the channel.

The Norwegian coast isn't actually a restricted water unless you go close in for shore action.

The Solomons on the other hand, the English channel, the Indonesian archipelago, the red sea or the gulf of Tianjin on the other hand are examples of very restricted waters where rules strongly favoring small and medium ships should apply.
 
getting experience navigating those areas, ship procedures and experience with cold climate maintenence. there is also a big health impact which i could argue would impact an admirals ability if he isnt used to it. Mostly its for gameplay. its a nice bonus for some nations
Would it make more sense for this to be governed by the acclimatisation similar to land forces, rather than a leader trait? That would make the ships that actually operate in cold waters (i.e. Murmansk) resistant to lold effects, but not freshply redeployed ships.
 
Can training or patrolling in Arctic waters give the Arctic trait for commanders?
 
Would it make more sense for this to be governed by the acclimatisation similar to land forces, rather than a leader trait? That would make the ships that actually operate in cold waters (i.e. Murmansk) resistant to lold effects, but not freshply redeployed ships.

Having a dedicated Arctic naval design would make the most sense, but I can see how an admiral can mitigate the effects of cold weather by applying past experiences.
 
I like the new sea terrain idea!
But quick question: isn't light cruiser suppose to operate well on open sea? I thought that was the one of main purposes of light cruisers.
Also any chance we might be able to see auxiliary ships?
 
Please give some thought to the difference between restricted waters and shallow waters.

All the restricted waters, not just the English channel, should have stacking penalties on capital ships. This should be independent of whether the sea area is shallow or not. If you are fighting for naval superiority in restricted waters then you should want to leave your battleships behind or bring just a limited number, but bring all the destroyers and cruisers you can get. The question of whether you should also bring submarines should be independent of this.

HoI games always have had ridiculous stuff happen in the English channel like U-boat sinking entire fleets of surface warships, or battleship fleets duking it out in confined waters where they (the fleets) don't actually have even enough space to turn around at combat speed, and the effects of small craft (which would realistically be a serious danger to large ships in the channel) aren't modeled in any way.

You have north sea and channel exactly the same territory. With effects on submarines only. While that is welcome, it's not enough to make naval warfare in that area really realistic. The channel was not a good area for battleships because of the narrow width allowing all kinds of small craft like torpedo boats to quickly sortie from minor ports, and because the channel just wasn't wide enough to allow for good maneuvering of the kind of larger flotillas that battleship combat would involve... The North area on the other hand had quite a lot more space to maneuver although of course the shallowness was just as bad, even worse, than in the channel.

The Norwegian coast isn't actually a restricted water unless you go close in for shore action.

The Solomons on the other hand, the English channel, the Indonesian archipelago, the red sea or the gulf of Tianjin on the other hand are examples of very restricted waters where rules strongly favoring small and medium ships should apply.

Sounds like the fjord and archipelago trait should be applied to channels as well.
 
This seems like it will have an interesting impact on submarine warfare. Destroyers have generally been the best at ASW, but it sounds like they will be operating at a disadvantage in deep waters while subs will be operating at an advantage.


On a related note, this seems brutal to submarines. Since it looks like the North Sea as well as the English Channel are Shallow Seas, I expect that holding Western France for basing submarines will be quite important.

Kinda the reason why Germany placed the French Atlantic areas under direct occupation in 1940, IIRC. :)
 
We have added a few new sea zones (the Aegean Sea and the Red Sea come to mind) but there will probably be another pass on naval zones before release. We are just waiting for a good point to break save games again.
When you rework naval zones, please try and find the time to fix the border between South Africa and Zambia. If the Caprivi Strip isn't included in this Africa update, I'm sure there will be a long wait before borders in the region are looked at again.
 
that would spoil the next expansion ;) it wasnt primarily naval focused
I think i know which books is about is about the allies mission in Norway and the sabotage of heavy water factory in Norway, and maybe a proper special tasks in the future as secret weapons :D
 
It doesn't sound like much of a rescue effort was made to rescue survivors of the Scharnhorst. (anyone know why that was?)

Maybe having naval superiority should increase the proportion of rescued sailors.
 
It doesn't sound like much of a rescue effort was made to rescue survivors of the Scharnhorst. (anyone know why that was?)

Maybe having naval superiority should increase the proportion of rescued sailors.
Or at least the winning side

Historically, submarines & flying boats would patrol for downed fliers that had to ditch; maybe some techs representing that

Edit 2: I'd like to see some way of representing scout planes such as the Catalina- long range aircraft that would add extra detection
 
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