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HOI4 Dev Diary - New Naval Combat

Hi everyone! Since forums were all down yesterday the diary is coming today instead :) Today we are going to look at core changes to naval combat coming in 1.6 Ironclad. We have already discussed how missions are changed as well as basics of the new spotting system in a previous diary and a future one will be fully dedicated to submarines so I will only cover them a little for how the interact with regular fleet battles today. So lets charge in!

Its best to start by looking at problems in the old system so you can see how we have tried to solve them and iterate. We identified the following:
  • Battles are extremely decisive so tiny mistakes have bad consequences
  • Combats tend to snowballs as everyone and their mother’s fleet pile in
  • A big fleet was always better, together with the above point promoting doomstacking
  • The interface gets very confusing as ships close with each other. Distance overall is very hard to show and balance.
  • It is easy to miss a combat happening while busy elsewhere.
  • Its “simulation nature” made balancing an incredibly hard problem. Resulting in things like the all-battleship fleets performing well.
“Battle-lines”
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To deal with distance and screening issues we have split up the battle in 4 areas per side to represent position and distances.

Screens - Your screen ships go here. Screens are the closest to the enemy and protect the ships behind them (details below).
Battle line - This is where your big guns sit. Heavy cruisers, Battleships etc. Anything with heavy long range guns. These guys also help to protect carriers and convoys behind them.
Carriers - Furthest back are carriers protected by the other two lines. This is also where convoys will be if part of the combat (say during invasion or a convoy raid battle).
Submarines - Under the sea. This area is actually two as we separate located submarines (which can be engaged with depth charges) from unlocated submarines.

By splitting things up in discrete distances unlike the old system we can more easily capture the impact of distance and positioning, and keep it easier to see what is going on at a glance.

The area they are assigned to depends on the weapons they have, which makes things tie in neatly with the ship designer. Rules for combat are now largely depend on how different weapons interact with the areas, so it is important to go over them before we continue. We also show these summarized at the top of the combat screen for quick information and to help you evaluate the combat situation:
stats.jpg

Light Guns - These are smaller caliber guns. The armament on destroyers/light cruisers and secondary armament on heavier ships. Their job is to hit and kill smaller fast moving ships. They generally do not have the armor piercing to lay down serious hurt on capital ships. Light guns attack ships one line over. So screen ships can shoot other screen ships, and when there are no more shoot the enemies capital ships. Capital ships with secondaries can fire from behind the safety of the screens at the enemy screen.

Heavy Guns - These are hard hitting armor piercing guns designed to take out big ships. They have trouble hitting small fast ships, but when they do it is for significant damage. Heavy guns have the range to fire over one of the enemy lines. So they will be hitting the enemy battle line even if it is screened.

Torpedoes - These are the big capital killers. They ignore armor, and have big damage but are terrible at hitting fast/small ships. Torpedoes can hit any line as long as it is not screened properly. So if your screening is down to 50% then half of the enemy torpedoes can be fired at your battle line, and if the battle line is also weak some torpedoes can slip through and hit carriers or convoys.

Anti-air - AA works a bit different. When firing back at enemy planes a ship will also get a part of the fleet’s AA armament to help it, so it’s quite nice to make sure your support ships (or battleships if you focus on carriers) are stacked with as much AA as possible.

Depth Charges - This is the only weapon that can hurt subs, and it only works versus revealed subs.
Carrier Planes - Carriers can carry different kind of planes. Naval and dive bombers help attack other ships and fighters help protect yourself. The whole air model in naval combats is now more in line with the rest of the game and takes place in the airzone as you would expect. So can now be disrupted etc. This fixed a bunch of issues we had with the interaction between land based air and carriers.

sub.jpg


Next to the weapon summaries we also display the side’s positioning value. This is a value simulating how well positioned your task forces are. A low positioning could for example mean that all your screens are scattered in a storm and your capital ships are wide open to attack. Positioning affects screening directly and a low value will directly hurt the fighting abilities of the ships as they wont be in optimal range, have another ship fouling the range etc. A big effect on positioning is the relative sizes of the fleets. So the bigger fleet will have an inherent penalty to its positioning versus a smaller, more easily controlled force. An admiral’s maneuver skill helps with this though. There are also traits like Lone Wolf and the Capital Ship Raiders tech from the Trade Interdiction doctrines that help increase this penalty for the enemy. The idea is to make smaller capital raiding forces more competitive if you tech right and have a trained Admiral in charge.

screening.jpg


Tooltips for ships now give great breakdown on where the damage is coming from so you can see how well (or not) a particular weapon type is doing, there are also totals summarized in the top of the interface.
dmg.jpg



Entering and exiting combat
After the initial battle starts, further task forces can join. When they do they get put in the “Incoming” box, much like before. The time spent there depends on their org levels. The lower the longer they have to wait to join. Org is affected by moving, but also by giving manual orders to fleets (we want you to plan ahead, not react for max efficiency). Whenever ships are called to a combat, they will take an organization hit, which slows down their joining. Similar delays also apply for missions like convoy raiding or escort at suboptimal efficiency so it’s harder to bring all your power to bear at the same time.

On the flip side, if you take out the enemy side before the incoming ships arrive, the battle ends and you can run away (or the sides have to re-spot each other if they still want to fight), the idea is to help subs and other raiders out by allowing fast hit-and-run battles.

run.jpg


As for exiting combat that is both something you can order directly and something that happens when ships take enough damage (remember, you set up aggression levels to control how risky you want your task forces to be). Retreating is a process that takes some time. It is affected by doctrines, traits, weather, terrain, and the speed of the ship. We show it as a progress bar so you can bite your nails as the enemy pride of the fleet slowly gets away. Note that we also now have critical hits which will slow down ships and making it harder to run - a ship with a jammed rudder has a wooping 90% penalty to escaping. Escaping is an important part in keeping battles from being too decisive.

This is also where submarines come in. They follow normal torpedo rules, but also free to circumvent them when it comes to escaping ships. So if you have subs hiding in your battle they can engage the enemy capitals as they start to run (of course this reveals them, depending on doctrine levels, leaving them open to return fire from anti-sub vessels).

See you next week for a look at submarines :)

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Rejected Titles:
- Sinking inside the box for a change
- Bravely retreating in the face of underwhelming odds
- Man, those guns!
- "Stop writing dumb titles and post already podcat!"
 
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hey @podcat what will the focus 'The Long Lance' do now that torpedo range is arbitrary?
It gets a screening penetration bonus. This works so that if the enemy screening is at 50% with the long lance it will treat that gap as bigger (20% bigger atm) meaning its turned into 40% screening effectively. if you are doing this you'll want to make sure you get the Lancer admiral trait which bumps it further as well.
 
Will it still be possible to fight carrier battles without getting surface ships involved?

Excellent Dev diary and answers. This is the question I would love to be answered because there are only two aggressive modes "engage or " do not engage", and ships that do not engage runs from a battle. Do aircraft carriers planes attack enemy ships if the fleet is assigned to "do not engage".
 
Is the 4-carrier soft cap still in the game?

Can Carrier secondaries engage enemy screens like battleship secondaries?
 
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It might be that both sets of aircraft are wiped out and the battleships continue to slug it out.

Only problem is this really never happened in real life where there were fleet carriers involved.

Per what Podcat said the only way to really have a Midway type battle is for both sides to have the CV fleets on do not engage and then run NAV missions in the sea zone. Otherwise ships from the TF's will fight gun battles and as soon as a screen or capital line is breeched the CV's will come under gun fire.

Will it still be possible to fight carrier battles without getting surface ships involved?

Only in the way described above.

Hello,

what about ammo especially for tiny vessels like subs & destroyer.

From what was said and how HOI has worked naval ammo supplies are not considered. But MAYBE another way to look at some damage is the running out of ammo where you have to go back to port to fix the ship and this then can simulate resupply. Not elegant but it's the closest you can get right now from what has been said.

@podcat; If i want my screens to stay with my carriers, can I assign them to do that and know the CLs and DDs will stay put? Will my carrier fighter aircraft have a mission to perform CAP over the carriers or escort my bombers or search for enemy vessels, primarily CVs, then BBs? Will my carrier dive bombers and torpedo planes have a choice of searching/bombing/torpedo or strike mission to known carrier? Will I be able to set priority of hitting carriers first, battleships second and never to waste ammunition on screens?

Nope you can't do that. Engage orders are for the whole TF and not ships in it as far as I can tell. If set not to engage then none of the ships will. If set to engage then all ships including CV's will. Otherwise you should create a SAG group set to engage and a CV group set not to engage but on NAV strike in that sea zone. Only way I can think of to do it.
 
Excellent Dev diary and answers. This is the question I would love to be answered because there are only two aggressive modes "engage or " do not engage", and ships that do not engage runs from a battle. Do aircraft carriers planes attack enemy ships if the fleet is assigned to "do not engage".

It appears you can only do this with do not engage and running a naval strike mission in the sea zone with the CV planes.
 
Cheers for the DD Podcat and thank you so much for giving naval combat a good overhaul :D. While the 'visceral' feeling of the old system felt nice on the surface, it wound up being a not-so-great simulation of how things actually happened during naval battles (from the perspective of a strategic wargame, rather than a Rule the Waves-style affair) and this looks like it will give us much better results, and hopefully make naval warfare a long, drawn-out struggle that'll draw us in for a good broo-ha-ha :). Very much looking forward to seeing how this plays in the released game once we get our mitts on it :D.

yes, the movement of the old one did feel nice for a while until it dissolved into a swarm you couldnt decipher anymore. I have some ideas to make this cooler in the future, but I am also aware you guys wanna play this dlc soon ;D so they are gonna need to wait to a patch or some such

Follow-up DLC to Man the Guns confirmed as naval in theme! Possibly called Swab the Decks? :D.

I am not an expert on the Pacific theatre, but AFAIK all sides expected that there would be gun-battles, but discovered that carriers had struck & gone before the conventional warships could get into position. Is that right?

As best I understand it, the two (related and often happening together) things tended to be that either one side had a disparity in surface forces (so the side with the smaller surface forces backed off after the carrier battles had happened - Midway is a good example here, the US did not 'hold the field' at the end of the day, but Japan didn't either, and while the US 'kind of' won the Battle of the ) and that strong surface forces that were left didn't like to 'stand and fight' if they weren't confident of protection from the air, particularly in the face of land-based airfields (so, for example, while the US nominally won the Battle of the Eastern Solomons, both sides withdrew, and Japan was arguably in a better position at the end of the battle, even if they'd taken greater losses, but as the US still held Henderson field on Guadalcanal, they didn't want to stick around and get hit by land-based air, so withdrew as well. If I remember it correctly, it's Friday morning here and my head feels like it's full of sawdust.

How about Italy?

I have no doubt Italy will get unique rules to reflect the very high levels of crew comfort on its ships :). Now this is a cabin....

ROMA130.jpg


On this ship - for those that like their naval pictures from the outside:

ROMA014.jpg


It gets a screening penetration bonus. This works so that if the enemy screening is at 50% with the long lance it will treat that gap as bigger (20% bigger atm) meaning its turned into 40% screening effectively. if you are doing this you'll want to make sure you get the Lancer admiral trait which bumps it further as well.

This sounds like a super-cool way of making the Long Lance matter in a historically plausible, easy-to-understand way - nice work :cool:.

Only problem is this really never happened in real life where there were fleet carriers involved.

It potentially could have at Midway if the US still had a surface force that could contest the Japanese fleet - both sides' air forces were more-or-less exhausted (the US less so, but they didn't have a heap of aircraft they could use for further strikes, and imo would have struggled to do decisive damage to a battle fleet's massed AA). Just because something never happened historically, doesn't mean it couldn't or shouldn't happen - particularly in a situation like carrier battles, where the small number of events we have to analyse makes potential variations outside historical events quite likely. That's just my 2 cents though, I haven't gone and build a bunch of remote-controlled battle fleets and air wings and tested it :).

@jju_57 Are you a spokesperson for paradox? Do you speak for @podcat? If not, what basis are you making these claims? Have you played the new game?

From the look of it, he's referring to statements made by the devs in this and other diaries (although wording it in a characteristically Jju-alike 'fairly strong' way - but Jju does this with everything).
 
I have no doubt Italy will get unique rules to reflect the very high levels of crew comfort on its ships :). Now this is a cabin....

View attachment 425185

On this ship - for those that like their naval pictures from the outside:

View attachment 425188

What the . . . . even though that had to be an officer's cabin, it's insanely luxurious. It sort of reminds me of the cruise my wife and I went on for our honeymoon. The only thing missing is the deck to sit out on and drink!
 
I might be easily missing something, but how do you actually shoot carriers now with your gunboats, assuming the former hide at the farthest rank and battleship main caliber can't hit this layer no matter what?

For instance, the scenario I have in mind is this. I've got plenty of land-based fighters (which will now actually protect your fleets, from what I've got) and those render enemy carriers totally useless. Yet I still want to see them sunk, hence a few of my BBs are sent for a hunt and assuming they either lock the carriers in a dead-end (say, the Baltic sea) or simply have a speed advantage, the carriers gonna be overrun and (mostly) toasted by guns, right?
 
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Admirals are in charge of Fleets. If you will create fleet consisting of just one task force you get basically the same result as admiral being in charge of task force.
Well I can see this becoming a slight problem If for example the fleets work like I think they do in order to use Admirals effectively you would have to misuse fleets and vice versa. ether that or you would have a specific fleet for scouting and one for capital ship engagements and yet another for submarines. this seems to undercut the idea that the task force system was supposed to make the naval game more user friendly.
In short I think a tiered command system that resembles the way armies work would be preferable, if only to make using multi role multi task force fleets practical.
 
@Axe99 I'm going to have to incorporate that picture into my AAR... seriously!
 
@podcat Sorry I am late on this request. But your dev diary a while back featuring the remake of the British tree, is there any way you could update the image of the national focus tree since you guys have added and adjusted it more since it was posted?
Thanks,
 
You guys are slaying it with this DLC. The naval combat upgrade looks like a major improvement.

podcat, it should be the maximum priority that carrier fleets, when in an area with an enemy carrier fleet present, that it is like cowboys dueling - meaning all their focus should be on the opposing carrier fleet and doing everything possible (to doctrine I suppose) to destroy them before they destroy you.

The air missions your carrier fleets roll out should 100% target the enemy carriers, if and when they are spotted, and nothing else until the threat is gone.

Totally agree with you here.

The spotting mechanics could really be used to increase the tension and realism in this. When every ship is plainly identified, it's easy to see who has the upper hand from the start. If the numbers and types of ships are harder to spot, however, the danger increases since you wouldn't know if you are facing a superior foe. It also would further encourage the need for patrol aircraft, subs, and radar. Breaking the combat down into sensing/tracking/targeting might be too tactical for a grand strategy game, but the hide-and-seek aspect of spotting and identifying could really enhance the action. It can also help put the player in the historical dilemma of choosing large or small carrier task forces to balance mutual support vs. being harder to spot.

Also hoping that improved AI amphibious programming is going to factor into MtG 'cause it would be a crying shame to have all these cool mechanics and Japan still never invades anything.
 
I have to say that I am most excited about how the CAG is now officially part of the airzone. It really didn't make too much sense how it was previously imho. Good stuff.
 
@podcat

When can we get a release date and changelog?

I want you guys to get this right, but do you really think ~a year between announcement and release is fair? :eek:
 
I hope they add more naval commanders. Even under the old system the number of named admirals for naval powers was tight. Now that they are encouraging more smaller "task forces," the number of admirals that will be needed will increase greatly. Heck, quite a few could easily be duplicated from existing doctrine choices (i.e. Nagumo Chuichi).
 
Not quite so related, but was there anything related to preventing the AI (Italy) from transporting all their troops over the Med for example with no nav-superiority and loosing 80% of their army?

Is there/will there be a flag which tells the AI to not transport across a sea if it's potentially dangerous?
 
Can you please redo the Caucasus provinces and states for more accuracy and realism? Additionally, the Soviet-Turkish border looks inaccurate due to the unrefined Caucasus provinces.