[2020] Dev Diary: 4th Anniversary + Patch 1.9.3

: You can find the details for this event on the announcement page [url=https://steamcommunity.com/ogg/394360/announcements/detail/2239925124653853627]here[/url].

Today's Dev Diary by Podcat[pdxint.at]


Hi everyone! This week is Hearts of Iron IVs 4th anniversary. I’ve got some cool data to share with you, new armor and radio packs as well as patch for you to celebrate! All of this releases tomorrow :)

A Look Back & Cool Numbers

It's crazy how Hearts of Iron keeps growing. I personally started with playing HOI2, and worked on HOI3 as a coder and game director on HOI4, and while people still call it a niche experience for WW2 buffs, it has also grown to be so much more (or us WW2 nerds are more numerous than we think :D). Around La Résistance release we clocked a new record on monthly players of 899k (the 1000 of you that didn't log in that month are responsible for my OCD flaring up!). HOI4 is quite unique in how stable the growth is. Most games that aren't multiplayer or the like usually has big dips between releases. I think the two big factors that keeps us so stable is the replayability as well as the amazing mods that keep updating giving people new stuff to play with continuously :) Here is what the curve has looked like over the years:



I also took a look at country popularity between the last year and the release year. These are the top 10 nations currently with comparison to 2016:



Most see relative reductions here because we have in general made a lot more nations playable with more focus trees and other improvements (in 2016 Poland had Hungary's spot while now its pushed below both Spain and Hungary). There are a couple of obvious increases who all seem to come from focus tree changes also :)

Allied Armor Pack

Tomorrow we also release the followup to last years Axis Armor Pack, this time for the allies. This includes 45 armored vehicles for USA, UK, France and Soviets. On top of this we also add in 32 tanks from the Colonel Edition for those nations also for a total of 77 :) This is one of the reasons that we stopped selling the Colonel Edition last month - it was making it messy to buy cosmetic packs and we didn't want to split stuff up further.

To make sure previous colonel edition players don't feel like they get as much, and also because its been such a great year for HOI4, we will be giving the whole pack for free to all those who had the colonel edition. Enjoy!

(the observant players may remember that there is some ships in the colonel edition also, people who have that will keep them but they are not included in this armor pack. We will sort those boat boys out in the future).

Below are some examples of vehicles included:



Allied Speeches

People seemed to like the radio addition last year, but this year we wanted to test something a bit different and more tied to gameplay. We have added 70 minutes of speeches from allied leaders and commanders, set them to music and trigger them based on ingame events. So for example when Japan declares war on USA you will be able to hear Roosevelt deliver his "a date which will live in infamy" speech.

Here is a sample using one of Churchill's more famous speeches to give you an feeling for how it will sound:



Its a great feeling when they kick in and adds some really nice historical flavor :) Note also that they are playable like any other tracks should you want to.

1.9.3 Patch

For this patch we wanted to focus on naval issues and improvements as we didn't touch that very much for La Résistance. To summarize the most important changes:

Naval tech rebalance
It's best to check the changelog for details here, but our goal has been to make tech investments into more efficient submarines more expensive and sub countering and investments into capital ships cheaper.

Convoys and stun-locking
A very annoying strategy in multiple and sometimes in SP has been being able to essentially stun lock an enemies transports of troops in place at sea by lots of small naval engagements with submarines. Even if well screened they still need to wait to retreat and then would get caught again and again, sometimes taking months to get across the atlantic. To deal with this we have increased the retreat speed bonuses from being well screened and also implemented a cooldown system. This system will give transports a cooldown after being caught where they can not be re-spotted again. The length of it depends on the length of their path as well as how well screened they are. For an unscreened vessel they will be caught pretty quickly in more interceptions while a properly screened one can continue on until the invasion beach if its not too far.

Carriers and other naval changes
Carriers in the pacific really struggle with the large air zones and the weather penalties. It didn't make sense to us to apply the area size penalties to a mobile base with so few planes, so now any mission targeting a specific location (port strike, CAS etc) for planes stationed on a carrier will not have this penalty.

On top of this it didn't make sense to have carriers planes suffer a 100% penalty from bad weather when land based ones had a much smaller one. While I doubt any planes could take off during a really bad storm, it makes little sense when we only really have one level of weather here to make it so brutal, so this penalty has been reduced to 80%. We also felt that if the weather is truly this bad guns really should be struggling more than they do as well as doubled that penalty to 20% to close the gap.

Carriers now also help the fleet overall. The side with the carrier plane advantage in the battle will penalize positioning of the other side, similar a bit in spirit to the effects of air superiority on land. We also made light guns a bit worse and buffed targeting and power of bigger guns to try and strengthen mixed fleets. We have also increased the base detection abilities of carriers a bit to better model how important they were for spotting enemies at sea.

Another thing of note is that we have fixed an annoying interaction between air superiority and naval spotting. Because air superiority applies on average on the zones a task force was operating you could shield them with planes in a zone they were not even in, which might be somewhere your enemy couldn't even reach and contest. Now it will be looking at the specific area they are in instead.

Out Of Syncs
Telemetry was telling us that the vast majority of out of syncs were happening in the first half of 1936, and for weeks we simply could not reproduce this inhouse, but recently we had a breakthrough. We found some data related to technologies that was not properly reset when entering a new game and this is hopefully the core reason for this. We will be looking at telemetry data to hopefully see the OOS frequency take a nose dive, because this stuff is truly hard for us to test fully ourselves, but we are optimistic!

Full Patch Notes:

################################################################
######## Hotfix 1.9.3 "Husky" ########
################################################################

##################################
# Balance
##################################
- decreased suppression value of SP-Art battalions
- decreased suppression value of SP-AA battalions
- decreased suppression value of SP-AT battalions
- decreased research cost on destroyer hulls
- decreased research cost on depth charge technologies
- increased research cost on 1940 and 1944 submarine hulls
- increased research cost on torpedo module upgrades
- decreased research cost of naval munitions upgrades for light and heavy guns
- decreased research cost of armor schemes
- increased the cost of initial radar tech, lowered cost on all other radar techs
- decreased IC cost of all ship heavy batteries
- increased damage of all heavy ship batteries
- increased piercing of all medium ship batteries
- increased damage of all medium ship batteries
- Carrier planes no longer take area coverage penalties on their targeted/ground missions
- Increased carrier hull surface detection base from 20 to 26
- Added a cooldown timer after naval transfers are engaged at sea and escape to avoid stun-locking issues with many small fleets. The cooldown depends on the screening efficiency of the defenders so a defended convoy will have a longer cooldown the better defended it is
- Added an extra speed boost to convoys retreat speed when screened
- Effective carrier plane advantage in naval combat now gives penalties to positioning for the other side
- Increased air-to-air damage factor in carrier battles from 5 to 6
- increase air attack targeting scoring for carriers to make them more likely targets for other carriers
- increased naval hit penalty from 10% to 20% in heavy rain
- reduced carrier traffic penalty from 100% to 80% in heavy rain
- Reduce heavy gun target signature from 90 to 80 and increased light gun target signature from 40 to 45 to make heavy guns a bit more versatile and light guns a bit slower at picking off screens
- Patrol convoy raiding and convoy escort missions now rely on local navy position for air superiority rather than average of air zones to stop high air superiority in a zone from saving the ships from spotting in another.


##################################
# Stability & Performance
##################################
- Fixed OOS related to asking an operative to resume their mission after the operation they are assigned to completes
- Fixed OOS linked to technologies not being properly reset between games
- Fixed OOS triggered by a country asking for manpower after a civil war
- Prevented crash when trying to respond to faction invite from a faction that no longer exists
- fixed a ctd that happens when a non-existing capitulated country checks for uncapitulation


##################################
# Modding
##################################
- Added play_song and scoped_play_song effects
- added on_war_relation_added on action (scope is attacker, from is defender)
- Made targeting weights for air-to-ship in naval combat moddable. See NAVAL_COMBAT_AIR_*_TARGET_SCORE defines.


##################################
# Bugfix
##################################
- Updated the forum link in main menu to match the new forum
- Bulgaria will no longer start with Flexible Navy focus completed in 1939

So what are we up to now?

We have been wanting to shorten the time between content update for a while and are going to take a serious stab at it now. That means that we are currently working on two things at once in parallel actually. In the pipe we have 1.10 ‘Collie’ as well as 1.11 ‘Barbarossa’. That's about as much information as I can give you right now. We are not yet ready to start dev diaries on ‘Collie’ but look forward to it some time after summer vacation. We have some massively awesome stuff planned and I think you are all gonna like it (if people wanna see the roadmap, it was last updated in this dev diary).

As part of the anniversary we are also doing a really cool new take on the 3-day war stream with influencers vs devs and... democracy?



Check out full event details here![forum.paradoxplaza.com]