Category Archives: Barotrauma

Barotrauma Source Code

Today I have some important news for the players and modders of Barotrauma. The full source code of the game is now publicly available on GitHub!

This doesn’t mean that Barotrauma is becoming an open source game in the “free and open-source software” sense. The intention is to give modders more freedom to modify and expand the game – the current xml configuration files are simply too limited for anything but the simplest of modifications. It doesn’t mean that we’re giving up working on the game either; now with the netcode update (mostly) out of the way, I’m as eager as ever to start working on new content again!

I know this is a risky move and something not many games have done, but I’m confident that it will open up whole new possibilities for the future of Barotrauma. In my opinion one of the things that made SCP – Containment Breach as successful as it is, was the openness of the development and how easy it was for the community to contribute, and I believe that going in a similar direction could be beneficial to Barotrauma as well. As with SCP-CB, people are of course welcome to contribute to the main game in addition to making mods. And I’d like to stress that I’m not expecting for the community to start doing our work for us for free. If someone ends up making substantial contributions to the development, I’m completely open to discussing some type of compensation.

So, if you’re a modder looking for more freedom than the configuration files offer or just want to take a look under the hood and see what makes Barotrauma tick, head to the following link:

Barotrauma @

Really looking forward to seeing where this goes and what kind of stuff you’ll come up with. :)


Netcode update

As many of you may know, me and juanjp600 have been working on rewriting Barotrauma’s networking code for some time now (oh god, I just checked and it’s been 9 months, why does time have to go so fast). The old networking logic was so full of issues (trivial to hack, constant desync issues, excessive packet rate) that we had to basically redesign everything from scratch, but based on the testing sessions I’ve been hosting recently, it really seems to have paid off. Now we’ve finally got proper authoritative servers and syncing logic that actually works(!).

The rewritten netcode is by far the most important change in the latest update, but it also includes some other new stuff, including reworked UI graphics, a sonar overhaul and bunch of bugfixes. See the full changelog here.

A few words about the sonar overhaul: now there’s the option to select between passive and active modes. The passive sonar doesn’t send out pings, but instead listens to sources of sound around the sub and the sounds reflected from nearby structures. This makes it possible to get a rough idea of the surroundings without alerting monsters (or enemy subs) with the ping. The sonar displays were also given a little facelift:


On another note, I haven’t forgotten the plans regarding opening the source code to modders – more about that later this week. 😉

Steam Greenlight and a brief status update

Last week, Valve brought us some big news regarding Steam Greenlight: they’re planning on getting rid of Greenlight “in the next few months” to make way for a new system called Steam Direct. Personally I think Direct seems like a reasonable move to fight the waves of shovelware that have been pouring through Greenlight for the past few years, but it will also most likely have a major impact on small indie devs like me. Developers will be required to pay a fixed fee for each game they submit through Steam Direct, and while the fee apparently hasn’t been set in stone yet, there have been discussions of a price from $100 to as high as $5000. If they end up going with a fee at the higher end of the spectrum, it will be a major setback to Barotrauma and my meager student budget. So, I thought it might be a good idea to try and get the game greenlit while it’s still possible!

Tl;dr: Barotrauma is now on Steam Greenlight!

In other news, despite the recent lack of updates we’ve made quite a bit of progress with Barotrauma. We’ve mostly been focusing on rewriting the networking code from pretty much scratch in order to get the multiplayer smoother and less vulnerable to hackers and fix to the desync issues the game’s been experiencing since the very first versions. The netcode is starting to be in a pretty good shape: less desync, less teleporting characters, proper authoritative servers and all in all everything is much more robust. We’ve still got a few features to reimplement, some issues to iron out and a lot of testing ahead of us, but we’re not that far away from being able to release at least a test version of some sort.

A beginner’s guide to injecting mind-controlling parasites into people

Step one:

Make sure you’ve been infected with the husk parasite. The most common way to get infected is an encounter with an active husk, but some well-equipped laboratories and research facilities may also house dormant husk eggs.


Step two:

Once infected, you may have trouble swallowing and your throat may feel sore. It is generally not a good idea to tell your fellow crew members about these symptoms, as it would most likely lead to a medical inspection and a dose of antiparasitic drugs. As the parasite grows, you may also find it hard or impossible to speak. If so, try to stay away from other people to prevent arousing suspicion.

Step three:

When the parasite reaches maturity, it extends its ovipositor out of your throat. The feeling may be somewhat unpleasant. At this stage it is highly recommended to wear a diving mask or other headgear to hide the ovipositor from the rest of the crew.

The parasite will slowly start taking over your entire nervous system, but this process can be delayed by working together with the parasite by spreading eggs into new hosts. Just find a suitable target and gently insert the ovipositor into one of their body cavities.

Multiple subs?

The idea of a submarine-vs-submarine game mode has been popping up quite frequently and now we’re one step closer to having one:


There were (and still are) tons of systems in the game that work under the assumption that there’s just one submarine, so even loading another sub into the level took a lot of rewriting. There’s still a long way to go until a fully functional submarine-vs-submarine mode, but adding some sort of small escape/attack vessels might not be that far away.

One idea I’ve been thinking of is adding a small “shuttle” that could periodically transport new or respawned players to the sub mid-round. It wouldn’t only reduce the time spent waiting for a round to end, but it could also create some interesting situations; handful of survivors trapped in a sunken sub waiting for the reinforcements to arrive, a swarm of sea creatures attacking the shuttle, a traitor taking control of the railgun while the shuttle is trying to dock…





Lighting improvements

Some small improvements to lighting in Barotrauma: added a bit of blur on the lightmap and changed the rendering order so that the walls aren’t full-bright anymore. I was really surprised to see how much better it looks with just those small changes:

barol1 barol2 barol3

The second picture also shows a small portion of another new addition: there are now procedurally generated alien ruins in the levels, with traps, new monsters and new alien items inside them. Artifact quests will definitely be more interesting now!

Barotrauma v0.3

The new version is up now! The changes to the way the game handles moving the submarine “under the hood” were definitely the the biggest and most time-consuming change in this update, and unfortunately it isn’t something that’s visible for the players (at least until underwater ruins and shipwrecks are added). There’s still quite a lot of other additions and a huge amount of bugfixes in the update, as seen in the changelog.

Here’s some gameplay footage that shows some of the new stuff:

Some new pics

Since the last update I’ve been mostly working on changing how the game handles moving the submarine which is why there hasn’t been much to show. In the current version the levels actually move around the submarine while the sub itself is stationary, which makes it really difficult to have multiple submarines in the same level, or any structures outside the sub for that matter. Even though a game mode with multiple subs isn’t on my to-do list at the moment (maybe at some point in the future though), some sort of explorable underwater structures (sunken subs, alien ruins…?) are a must, so I needed another way of moving the submarine.

How it works now is that neither the submarine or the level actually move: instead there’s an invisible submarine-shaped physics object moving around the level and the insides of the ship are just rendered wherever that object is.

Here are a couple of screenshots of some other additions:


Some UI improvements


Items and devices are grouped by category and the fabricators actually work now


Nicer looking levels and a new enemy


The crew members now have an AI and can take orders from the player