• We have updated our Community Code of Conduct. Please read through the new rules for the forum that are an integral part of Paradox Interactive’s User Agreement.

HOI4 Dev Diary - Supply and Mulberry Harbors

Greetings all, and welcome to today’s dev diary on the huge supply system update coming with the Barbarossa update. Before we begin, I’ll leave a heads up that this will be the last dev diary before we break for summer, so don’t expect anything new until some time in August at the earliest.

Since we last talked about supply, a few things have changed. We found that the way truck need could take off and spike was hard to deal with and that watching out so you didn't overload individual supply hubs was a bit too intensive. We also felt that the way the mapmode worked made it very difficult to project how well supply was flowing.

The iteration we have now aims at addressing these shortcomings. It's now possible for divisions to supply from multiple hubs. Trucks are now less of a strict necessity, rather something you can assign to hubs to make sure they can project supplies further away. Finally, the mapmode has changed to better show the spread of supply as well as current status for divisions.

Supply flow

From each hub connected back to the capital, potential supply is projected outwards - adding up when overlapping. This is represented by the brighter colors below. For each province in distance that supply needs to travel from a hub, there is a reduction in the amount as some is lost. The amount depends on various factors like terrain, crossing rivers etc. The dark purple areas below are reduced to local supply only, and the highlighted red-orange areas indicate locations where there are units suffering from significant supply issues.

1.png


In the picture above, the Ukraine/Caucasus front is mainly struggling because it is overextending before the captured rails have been converted, so a lot of the rail network there is not operating. When a railway is taken over there is a longer cooldown when it gets converted for use by you (representing a combination of repaired damage, gauge-alteration, and general maintenance), and without connected hubs supply won’t flow.

How much you can output from each hub depends on the level of railways leading back to the supply capital, and the total max there depends on your industrial base (so Luxemburg can not feed as many as soviet union, for example).

2.png


Here, the clock indicates rails that are not yet converted, and the hub icons with red crosses indicate that they do not connect back to your network.

Motorization

To increase the range of a hub (perhaps to help supply the front above better) you can choose to improve the motorization level. The horse icon on the right indicates no motorized supply from the node, but you can opt to toggle it to a higher state of motorization. Be careful, as this will cost you trucks which are taken from the stockpile.

3.png


It is also possible to set the motorization level on an army, in which case it will automatically toggle on motorization for hubs that it uses without requiring further interaction from the player.

4.png


There are also some other options on a hub. The star icon lets you move your supply capital to a new location, provided that you have sufficient surrender progress. This lets you get around issues where your capital ends up cut off or surrounded, but also comes with a period of bad supply as the new location is prepared.

The blue flag next to it lets you control allied access to the node. This can be a great way to flag to an AI that you do not want them on your front, or to stop them from joining a tight landing situation.

The rail icon lets you quickly switch to construction mode and extend rails from there while the green plus will automatically queue up construction for rails to combat any bottlenecks your node may suffer from back towards the capital. The chevron icon lets you prioritize train allocation if you are running low.


Floating Harbors

As part of No Step Back, we’re introducing a new dimension to naval invasions. Floating, or ‘Mulberry’ harbors can now be constructed once the appropriate research has been completed.

5.png


These weighty and expensive pieces of infrastructure (don’t look too close at the numbers above hehe) aren’t intended for every-day landings, but are instead intended to represent the equipment used in large-scale operations such as the Battle of Normandy.

6.png


Naval invasions utilizing a floating harbor will be represented by harbor apparatus placed parallel province targeted by the invasion, and will immediately create a stocked supply hub at their location:

7.png


Used carefully, one or more mulberry harbors can keep a sizable invading force supplied without requiring the immediate capture of an important enemy harbor. Of course, harbors should remain amongst the first targets of any successful invasion, and the supply hubs created by a floating harbor will be temporary; lasting a matter of weeks or months, depending on the strength of enemy air superiority and other factors.

Of course, there is yet more to cover regarding supply, and we'll have another diary on this subject in the future, but I hope you like what you've seen so far and we’ll be seeing you again after summer!

Oh, and one last thing - one of the new loading screens for NSB is this awesome Polish cavalry, so we figured we should share it as a summer wallpaper for you (fear not, there will be a soviet one eventually!)
1625046148370.png

The vision behind the painting was to present a more historically accurate depiction of the Charge at Krojanty. This was an engagement in the opening days of WW2, where the elite Polish cavalry surprised a German infantry unit at rest, charged before it could prepare for defense, and dispersed it. They later withdrew when faced with German armored cars.

This battle is famous because it started the, often officially repeated, ahistorical view of Polish cavalry charging German tanks and we wanted to try and make something more accurate (ignore the backdrop. we couldn't resist an epic sunrise on a field, but I hope the feel is there).

We have attached 3 different aspect ration wallpapers for you, and we can't let this opportunity go without a shoutout to @CreamGene our talented 2D artist responsible for this artwork.
 

Attachments

  • NSB_Wallpaper_2_4k_4.3.png
    NSB_Wallpaper_2_4k_4.3.png
    14,1 MB · Views: 0
  • NSB_Wallpaper_2_4k_16.9.png
    NSB_Wallpaper_2_4k_16.9.png
    11,3 MB · Views: 0
  • NSB_Wallpaper_2_4k_16.10.png
    NSB_Wallpaper_2_4k_16.10.png
    12,3 MB · Views: 0
  • 191Like
  • 141Love
  • 9
  • 4
  • 4
Reactions:
With supply trucks now a buildable thing, can they also be destroyed? I recall one of the great impacts aircraft had during the war was in destroying soft targets like supply vehicles.
yeah. there will be a diary about those aspects of supply later on

Does motorization use fuel passively?
Not atm, we felt it probably isnt worth the complexity

Why is supply in Lowlands better than in Berlin?
it isnt really, its more that the mapmode favours multiple sources quite a lot vs one very large source but limited by fewer rails etc. might be worth some tweaking
 
  • 42
  • 37
  • 10Like
  • 2
  • 1Love
Reactions:
Hey, I think the wallpaper looks great - possibly the best one yet.

One question I had though which is a little abstract to the topic is would you consider changing how UK deals with releaseable nations. There are many countries you can no longer play in Ironman with ease because of the gamerule stopping them from releasing most countries. I was just wondering if it would be possible to alter the gamerule from a flat out ban to more like - You are only able to release one country every year/6 months?

That way if you wanted to play lets say Nigeria or Malta - you can now do so without console commands in 36.

Regardless, thanks for the diary and enjoy summer break!
 
  • 5Like
Reactions:
Damn, at first I thought "another supply diary?" but wow, this one was really nice. I really liked those changes, especially controlling ally access and floating harbors seem very interesting, good job from devs.

Now, how am I going to wait till August?
 
  • 3Like
Reactions:
Im curious, since the suppky system always heads back to the capital. Does this mean i can break the complete Supply System by encirceling the Capital of my Enemy?
Like in HoI2 where this was all you need to do in order to beat everybody.
 
With the conversion of rails feature, is the length of conversion modable?
For example to have very short conversion time in a Civil War or quite short times if overtaking a country with the same rail gauge atleast.
I cant remember if we fixed it already or not, but its on our radar. its been a bit punishing in civil war with the same timers :)
 
  • 28
  • 11Like
  • 1Love
Reactions:
Not atm, we felt it probably isnt worth the complexity
Hope this gets reconsidered. I don't get why you added fuel if we then don't.... use fuel? And of course the Germans *couldn't* motorize their supply lines because of this issue.
 
  • 40
  • 7Like
Reactions:
The blue flag next to it lets you control allied access to the node. This can be a great way to flag to an AI that you do not want them on your front, or to stop them from joining a tight landing situation.

This is by far the most important part of the supply rework. Having a front clogged up with AI allies is quite disheartening. I do hope you continue to invest in iterating this part of the feature until it works well.

The other stuff like the harbours looks nice, but only the blue flag bit really matters IMHO.
 
  • 3Like
Reactions:
This looks really good! I cannot wait to see how the AI uses this. Thanks for the wallpaper, it looks really good! The more and more I see of NSB, the more I'm convinced that this is going to have a ton of potential and going to possibly be one of HOI4's best DLCs (ever?).

Only concern I have is that I noticed the Soviet AI in that picture didn't appear to be doing so good down on their Southern Flank, which is quite normal, expecially late game. Will the Soviet AI get any touch ups to assist it in fighting the Axis 1V1 on the Eastern Front?
 
  • 3Like
Reactions:
taking for example the immagine of german invasion of sweeden, are naval invasions an airborn assaults a good method of cutting train supplies of the enemies in tight regions? (taking the fact that yo are literaly taking a province on which a train line is going)