After a bunch of beta testing, it's time to release the new networking code for everyone. There are still rare desyncs, but the game is able to recover from them, and I hope to hunt down the last few issues soon.

• Much faster loading and saving
  
• Preview info of saved games
  
• Much faster checking of Steam subscriptions on startup
  
• Smoother, more resilient multiplayer
  
• The ability to load modded ships when you're missing some required mods
  
• Mechanical tentacles
  
• Mostly up to date translations

Modder note: The game now also checksums the files in data/lang, so if you changed them, it will complain that the game data is wrong. This is to prevent desyncs from happening where two players' games end up naming things differently.

I've been working on improving the game's networking and save/load functions, and it's now time for a last open beta to make sure it all works before it gets officially released. So if you're interested, switch to the "mp_beta" branch to experience:

• Much faster loading and saving
  
• Preview infos of saved games
  
• Much faster checking of Steam subscriptions on startup
  
• Smoother, more resilent multiplayer
  
• The ability to load modded ships when you're missing some required mods
  
• Mechanical tentacles
  
• Bugs, potentially

If you try it out, please document and tell me about any problems you run into! Don't assume that I already know a problem exists. You can contact me here, or on the Steam forums, or on Discord, or via email to zarkonnen@gmail.com .

To switch to the beta, right-click on the game in your Steam library, choose "Properties", then select the "Betas" tab from the window that appears, and finally "mp_beta" from the drop-down in that tab.

• Fixed performance problems with grenadiers and other boarders.
• Saw blades and other ammoless weapons once again will fire at harmless targets if they have nothing better to do.
• Temporarily disabled multiplayer chat overlay, as it was causing lag spikes. It will be fixed and re-enabled soon.
• Fixed crash caused by ships producing less than 0.5 command points.
• Fixed rare crash in file screen.
• Fixed weird behaviour in file screen when you hit enter with nothing selected.
• Limited number of particles in a combat to 4000. This can be changed by editing launch_settings.json.
• You can now deactivate the enemy combat AI entirely, useful for testing purposes.
• Cow-catcher ram is now called wurm-catcher ram, as there are no cows in the game's setting.
• Instead of tips you now sometimes get in-universe ads in the world generation screen.
• Modding: Ability to hook charges/tinctures/layouts into existing heraldic styles. See Modding Notes.txt in the game data folder for details.

Well, looks like you all really enjoyed this years April Fools for Airships, which introduced a set of in-game ads for a variety of strange and frightening products and services. While April 1 has passed, by popular request, the ads will resurface occasionally in loading screens.

If you missed them, here's all the ads, plus some commentary:



These were a real product in late 19th century America. I changed frighteningly little in this ad from the original. Given the way they're advertised, you'd expect them to contain cocaine or amphetamine, but it was actually worse: they contained strychnine - hence the line about rat poisons at the bottom. I also drew the third face in the picture to show signs of risus sardonicus, also know as rictus grin, which is a symptom of strychnine poisoning.

So why would you put strychnine into these pills? My guess is that as a nerve poison, a small dose would make you tense up in a way that might be mistaken for increased vigor.



"Make easy money at home" scams have a long history extending to today. Of course, no one actually wants those geckos you're breeding, and the FAQ I wrote suggests that the real business model is selling overpriced anti-gecko tincture to the marks.



A silly pun. The three monks have beards that look like monk's beard - barbe di frate, a type of vegetable. I always get confused and call it frate di barbe instead - monk of the beard.



Floatmead is full of Suspendium and hence provides unique challenges in drinking. The contraption here is basically an upside-down Belgian beer glass holder.



These are partially a reference to Triscuits, a long-running brand of biscuit with an unclear etymology. Likely they were named Triscuits because they were baked with elec*tri*city. But "biscuit" really means "twice baked", so it should be "thrice baked", which they aren't. Anyway, Heptascuits *have* been baked seven times, rendering them akin to some new kind of metamorphic rock with infinite shelf life and zero edibility. Which brings us to the other reference, ship's biscuits or hardtack, which were the standard ship's ration during the age of sail, and only slightly more edible. Remember: if the biscuit floats, it's safe to eat. If it sings, it's not.



In our world, "moon hoax" refers to the conspiracy theory that people never actually landed on the moon. In the world of Airships, there are three moons, and no one claims to have visited them. But they're central to the dominant religion of the world, so this "moon hoax" book is really an attempt by cultists to recruit new members. There's a long tradition of cults and other fringe organisations operating their own tiny publishers to create materials and sometimes act as fronts.



Mushroom Wine from the Unterzee! This is a reference to the Fallen London universe, and Sunless Sea in particular. I'm really pleased with how the drawing of the mushrooms turned out.



This is a reference to that infamous scene in A Clockwork Orange. See "Burgess" and "Alexander Lane".



Of course I had to include a dubious "tonic". There were a lot of those in the 19th century, and some of them are in fact still around. Their ingredients ranged from harmless plant extracts to highly dubious substances, including, again, strychnine. The joke - yes, this is where I explain all the jokes - is that it's deliberately left unclear what the relationship of spiders to this tonic actually is. For spiders, against spiders, made with spiders, who knows? The offset of the color and the black is intentional, of course, meant to evoke shoddy printing.

Finally, if you look at the detail on the bottle, the ingredients include:

• Pennyroyal - a toxic flower traditionally used as an abortion-inducing tea.
  
• Castoreum - beaver scent gland extract used in perfumes, and as a food additive in the 19th century.
  
• Parsley - a common and pretty harmless herb. It might help with digestive issues.
  
• Certain Essential Saltes of Animals - a reference to HP Lovecraft's The Case of Charles Dexter Ward.

The Six Day Stilt is a location in Caves of Qud, another favourite game of mine.



Moustache tonics are a real thing. Here's one with Suspendium in, allowing for truly improbable arrangements of facial hair.



The shape of the landship is based on a giant mining truck. Note also the suggestion of two watchful eyes in the trees.



Another product that is far less altered from its original than you'd expect or hope. Wine fortified with cocaine was a real thing, and yes, there really was a brand that claimed to be endorsed by the pope.



The world of Airships lacks cows, so they have to make do with Corned Wurm, made from giant angry lizards.



Also available in a substitute version. Please don't ask what it contains, you would not like the answer.

Finally, here's a list of ideas that I didn't get around to, because I didn't have the time, or I didn't know how to draw them:

• Hiddelsten's Vibrating Underwear
  
• Mr Stockton's Safe Aerial Descent Device
  
• The Todestrieb Institute recommends that men, women, and children of all ages smoke thrice daily to calm the lungs, clear out harmful Suspendium dust, and prevent disease from taking hold. (I nixed this one because I didn't want to make the lives of recovering smokers any harder.)
  
• Try Floatcheese from Floatgoats!
  
• The Floating Fireplace: Spreads Light and Warmth throughout the House
  
• Mizzenmast's Candied Jellies
  
• Athory's Blood Purifier Engine

Q Why?
A To create new revenue streams and maximise shareholder value by exploiting existing IP.

Q I don’t see any ads.
A The ads become available at the start of April in your local time zone, and require the game language to be set to English, French, German, or Russian. Also, make sure that you are not in a beta branch on Steam.

Q I do see ads and I wish I didn’t.
A If you really must drive me to ruin with your unwillingness to see ads in a game you already paid money for, go into Settings & Info in the main menu to turn them off.

Q I’m not entirely clear on how to purchase the advertised items.
A You may request a detailed catalogue of items by sending two Gug Shillings or other coins of equivalent value to 11 Uncouth Road, New Glottenbourg.

Q Is spider tonic made out of spiders? Is it to prevent spiders? Is it for spiders???
A What ridiculous questions. Everyone knows what spider tonic is.

Q Are Ambition Pills safe to take?
A We have heard no complaints.

Q How do I drink floatmead?
A Bow your head and then carefully invert the flagon to let the mead float upwards into your mouth. Swallow carefully.

Q Help! I have bred too many geckos! They’re in the walls! They’re everywhere!
A Send a letter to 11c Goat Lane, Cogburgh. Enclose 3 florins to receive our highly efficaceous anti-gecko tincture.

Q I have attempted to eat a Heptascuit.
A Send a letter to 11d Goat Lane, Cogburgh, enclosing your teeth.

• Added an "anchor" toggle that lets you exclude ships in a fleet from being selected by default.
• Ships no longer fire on harmless targets, wasting ammo.
• Ships no longer think that unarmoured decorative spikes are vital enemy systems that must be destroyed at all costs.
• Fixed some minor GUI/display bugs.
• Limited length of ship and empire names to 50 characters to prevent messages taking up a distracting amount of space.
• Game preferences are now stored in the game data directory (%APPDATA% on Windows). This improves performance of the open file screen and allows you to do a full, clean reinstall.
• Improved game performance by a few percent.
• Registration for non-Steam users works again.

These balance changes were suggested through a community process on Discord. Thank you all for participating!

Modules

• Saw blades damage 30 -> 25, but increases to 30 with advanced metallurgy tech.
• Targeting computer weight 500 -> 400.
• Grenades base damage 20 -> 25.
• Deck gun HP 40 -> 50, added light steel armour, reduced crew requirement by 1, cost $50 -> $70, +10% accuracy, +25% shoot troops range.
• Increased kinetic bomb accuracy by 50%.
• Engine pod: added light steel armour.
• Suspendium ray damage: 15 dmg x 12 shots -> 12 dmg x 12 shots.
• Pressurised suspendium dust tank lift 1200 -> 1400.
• Grapeshot cannon damage: 7 dmg x 14 shots -> 8 dmg x 14 shots.
• Aerial charge: +40% accuracy, +50% speed.
• Fire door weight 20 -> 10.
• Triplane, Biplane, Bomber, Torpedo bomber: modules no longer produce drag.

Armour

• Dragonhide HP 60 -> 75.
• Massive stone wall HP 100 -> 130.
• Reinforced wooden armour weight 15 -> 12.
• Shell armour cost 10 -> 6 (5 -> 3 in conquest).

Decorative/structural modules

• 1x1 slope weight 3 -> 2.
• 3x1/1x3 slope weight 7 -> 6.
• 4x1/1x4 slope weight 9 -> 8.
• Round corner weight 4 -> 3.
• Concave corner weight 3 -> 2.
• 3x1/1x3 curve weight 7 -> 6.
• 0.5x2/2x0.5 slope weight 3 -> 2.
• Crenellation weight 10 -> 5.
• Stained glass windows now have the same stats as ladderless corridors.

A whole lot of new sails courtesy of Orang. The old sails still work but can't be placed anymore. The new sails have fewer restrictions, and various advantages and disadvantages. I also updated a number of AI ship designs to use the new sails.



A whole lot of new armour and armour variants, mostly courtesy of YellowMiner.



New heraldic charges: sextant, chalice, fist, and new coat of arms layouts: orle and double tressure, plus a bunch of AI-only ones.



New set of AI ships by Orang, in an Aztec-inspired style.

A new mechanic for calculating a ship's air resistance and hence speed from its shape. See the new drag overlays in the ship editor.

I also added thin slices of dust tanks and dust tank envelopes with ladders in to allow you to easily fix drag issues caused by having struts go through tanks. Take this example ship:



And compare it with this one, where the struts have been replaced to allow for better airflow:

• Flamethrowers provide a steadier stream of flame.
  
• Bomb accuracy is no longer affected by firing mode or weather effects.
  
• Reduced restrictions on dorsal and ventral turret placement.
  
• Hussar modules are now armourable. You may want to go back to your designs that use hussars and add armour.
  
• Fixed graphical glitches with biplane hooks and damaged bomber planes.
  
• Fire burns longer, does less damage, spreads faster.
  
• Unimportant building fragments are now more aggressively deleted after battles.
  
• Increased normal propeller propulsion by 25% and small propeller by 100%.

• Fixed problem with editing landscape that placed soil underneath everything you put down, which made e.g building trees hard.
  
• Buttons underneath the edit ship panel are no longer active or highlighted.
  
• Removing decals now looks at the "place underneath" toggle to see which decal to remove.
  
• Duplicating decals now also duplicates their paint.
  
• Duplicating modules now also duplicates their window configuration.
  
• Invading fleet indicators now show time to arrival.
  
• Monster nest upgrade popup now properly pauses the game in single player.
  
• You can now access the game settings from conquest mode and some other places.
  
• Nicer-looking sliders in the settings.
  
• Buttons and other clickable things in scrollable areas no longer extend beyond their area.
  
• Updated heraldry editor: Each charge is now in a separate tab to make it less cramped.
  
• Fire noises and other loops now stop playing when you pause the game.

• Improved boarder pathing on the outside of ships, especially concerning sails and other geometries with a lot of empty space.
  
• Fixed some AI building designs pointing the wrong way.
  
• Fixed a replay desync bug.
  
• Fixed outline display of selected decals in flipped ships.
  
• Outside view is now toggled off when you switch to refitting buildings from the defences screen.
  
• Fixed bug where placing modules would use the wrong armour variant.
  
• Fixed bug when placing a module where it looked like it would join up to another module, despite that module not having a door in that place.

• Coats of arms layouts are now fully data-driven, so you can create your own layouts. Finally. That's one of the last major bits of hard-coded information in the game.
  
• You can now derive module types, armour types, and decal types from others earlier in the load order. (Earlier in the same file, or in a file with a name that comes earlier alphabetically.) See ArmourType/Wood.json, ModuleType/JUNK_SAIL.json, and DecalType/JIB_SAIL.json for examples.

• If you run the game in non-windowed fullscreen and alt-tab away, it stops completely, which breaks multiplayer. Use windowed fullscreen for multiplayer.
  
• Missing translations.

I'm working on an entirely new system for saving and syncing conquest games. It's currently in beta, and it's not certain that it will make it into the game yet, but I thought you might enjoy a dive into the why and how of it.

So yeah, this is a pretty technical post you can just skip if you're not into programming. tl;dr is: I'm doing things to make the game go faster.

There's two closely linked things here: saving the game, and calculating checksums to make sure that multiplayer games haven't desynced. Desyncing is what happens when the realities of two players in an MP game diverge, which is of course bad. Being able to detect it helps me fix bugs that cause the game to desync. Long-term, I hope to also add in functionality for desyncs to heal automatically.

Currently, both save and sync are very simple: the entire game world - map, empires, ships, landscapes - is converted to the JSON data format, basically one long blob of text. When saving, that blob of text is written as a file to disk. When syncing, the game calculates a checksum of the text and compares it to other players' checksums to make sure they're in sync.

But that's a lot of data, especially in the later stages on a large map. Dozens of megabytes. And of course the game world can't change while it's being saved, and so when the game syncs or autosaves, there's a noticeable pause. Sometimes, a very noticeable pause that causes your multiplayer game to steadily fall behind, because it can't keep up.

The new save system does two things to fix this, both a bit fiddly:


Most of the game world doesn't actually change between saves. A ship that's just flying around without engaging in combat doesn't change. The landscapes of peaceful towns, with nothing crashing into them, also don't change. So re-creating all the JSON data for them isn't actually necessary. By splitting the save game into a bunch of smaller files, one for each landscape and ship, the game can avoid doing most of the work of saving.

The hard part is that it has to know when a landscape or ship did change, which means that these things now need to keep track of a version number. That version number needs to be increased whenever a change happens. If not, the save will be partially outdated.

Conveniently, I realised that during development and testing, the game can produce the JSON for things that are supposedly unchanged, and compare it with the information that's in the file on disk to see if it really hasn't changed. This lets me root out cases where the version isn't getting updated.


JSON is a convenient format, but it's also very bulky. It's text-based and each data field is individually labelled, which makes it human-readable but verbose. Completely changing the data format of the game would be a huge effort. Instead, I created a more compact representation of JSON. (There's probably a lot of compact JSON representations out there, but this one is mine.)

There's a bunch of minor gains to be made. For example, the number 9845329 takes seven bytes to store in JSON but only four if you store it as an integer number. A small number like 109 fits into one byte.

The major gain is not having to repeat all the names of the fields. For example, each crew member on a ship stores a "weaponReload" value. On a ship with 100 crew, this means the letters "weaponReload" are repeated 100 times, which is 1200 bytes just for that. But in a compact format, you can just use "weaponReload" once and then refer back to that text using a back-reference that uses far fewer bytes. Because most of a JSON file's size is made up of field names, the total size of this new format is a fraction of the old one.

A back-reference here means that instead of spelling out the text you keep track of all the bits of text you used previously, and then refer to them by number when you need them again. For example the following sequence of words:

fruitbat, fruitbat, llama, fruitbat, iguana, squirrel, llama

can be abbreviated to:

fruitbat, 1, llama, 1, iguana, squirrel, 3

Where the numbers represent the position in the list where a word was first encountered.

What makes changing formats hard is that it needs to have 1:1 fidelity to JSON. You should be able to convert any JSON into this format and back again without losing or distorting any information.

But wait, why do we care about a compact format? We want a fast format! Well, conveniently those are very similar goals. Having to glue together far fewer bytes in less complicated ways makes this format faster. And having to write fewer bytes to disk also makes saving faster.


So by combining these two techniques, saving and syncing will take two orders of magnitude less time. It's more work, but it's also necessary.

You might be wondering why I'm messing around with save formats instead of working on the diplomacy update, but the way I see it, I can't do a big update and tell everyone to play multiplayer games when there's problems like multi-second sync pauses still happening.

• Improved user interface for selecting ship names: You can now set a prefix for your ships to have, and you can automatically choose distinct names or numbers when building multiple ships.
  
• The fleet list now has a compact mode and a select all button.
  
• You can replace modules, armour, paint, and decals in the ship editor by selecting them and choosing "replace".
  
• You are no longer prompted to name dragon riders and fleshcrackers.
  
• Toggle for switching to placing decorations underneath the ship.
  
• All decoration types can now be placed underneath the ship, including flags, coats of arms, and name plates.
  
• New AI fleets by Eliphaser, JimmyJam, Proton, 14pat and me.

• Planes go back to repair and rearm, and obey commands again.
  
• Showing module ammo per shot/clip again.
  
• Date panel moves to stay visible when fleet is selected.
  
• Fixes to tentacle AI.
  
• Boarders no longer get amnesia from going through doorways or dropping short distances. (Yes, they had doorway effect!)
  
• Boarders will now climb down landships and buildings when stuck on them.
  
• Planes no longer keep attacking buildings that used to be enemies but are now friendly.
  
• Crew no longer spawn exactly on top of each other, giving the appearance of missing crew.
  
• Planes using their weapons now reset the draw timer.
  
• The insides of modules with no armour are now drawn even when zoomed out.

• Adjusted biplane hook pricing to be consistent.
  
• +25% accuracy for landships and buildings.
  
• High Pressure Jelly now also increases flamethrower projectile speed.

Until recently, time has been a bit... vague in the game. Ships took some time to build, some time to move somewhere. But it's useful for players to be able to tell how long a process will actually take.

Which led to the question: how much in-game time passes in a second of the player's time? Obviously, an airship takes longer than a minute to build, so there's some time warp factor at work. Interestingly, ships do have a speed expressed in km/h, and since they move at a certain speed on the conquest map, picking a time factor also implies picking a scale for the map.

So I started juggling around some numbers and trying to figure out a time factor that felt right, that didn't make the map weirdly tiny or huge. In the end (and after some player feedback) we've ended up with one in-game day taking 0.4 seconds of player time.

The second question was how to display this time. Airships is set in a fictional universe, so it would be jarring for dates like "November 5, 2020" to appear in the game. At the same time, players need to have a reasonable grasp of timespans. A month should be roughly thirty days, a year roughly 365. A date like "six-moon, ninth period of the goat" or a time interval like "four plorkengs" tells the player nothing.

Then Orang on the Discord pointed out that the calendar should be lunar, given that the religions in the game revolve around the moons. Lunar calendars also have the advantage that each month is the same length, and given that I didn't want to go even more overboard with all the intricacies of real calendars, that was a nice simplification.

So the calendar in the game is a lunar one, where each year is 13 months and each month is 28 days, for 364 days in a year. On Earth, lunar calendars require constant adjustment so they don't drift out of phase with the year, but in the world of Airships, the year is conveniently really exactly 364 days long. The month names are taken from the old Babylonian calendar.



Of course, the world of Airships has three moons. The calendar uses the cycle of the largest one, but there are two others with different cycles.

And this being Airships, the moons are moddable. Yes, the game has data-driven moons. And data-driven calendars, which can be different for different players.

Here are the moons:




28 day period. The big moon that has the major influence on the tides. Associated with fertility. The current mainstream Trilunar religion was predated by a Mono-Lunar religion that only worshipped this moon. There are still Monolunarists around, mostly in rural areas, and they're tolerated if considered backwards. And there's varying enthusiasm for the worship of the two other moons within the Trilunar church as well, bordering on crypto-monolunarism.




61 day period. When Tessagon is full, there is a minor religious festival where people get together in their communities, relax and get drunk. It's also considered a good time for fishing.




109 day period. A smaller moon with an eccentric orbit. The sophisticated theological position is that Mith is the moon of things that are unexpected, unplanned, and out of season. The folkloristic view is that it's the moon of death, accidents, and monsters. A child born when Mith is full is considered cursed.

The major religious celebrations happen when two or three moons are full at the same time. Ea and Tessagon coincide every 1708 days, and the festival is a time of renewal. Mith and Tessagon coincide about once every 18 years, and that festival is a raucous but spooky celebration. Ea and Mith coincide about every eight years. This is a muted festival, and its main function is that debts are cleared and illegitimate children are accepted by their families.

Finally, all three moons are full about once every 511 years. These grand conjunctions are considered the start of a new epoch, though history rarely obliges. The old empire fell partway into the current epoch, on an indistinguished day. Other combinations also happen every 511 years, like the day when Ea and Tessagon are full and Mith is nowhere to be seen, or the darkest night, when there are no moons shining at all.

So if there are Trilunarists and Monolunarists, are there Bilunarists? Well, yes! Three kinds, because there's three combinations of two moons to choose from.

The ones that believe in Ea and Tessagon, but not Mith are the most numerous. Worship of Mith and the associated festivals are not very popular in some regions. While declared Ea-Tessagon Bilunarists are rare, there are plenty of congregations that choose to downplay or outright ignore Mith.

Believing in Ea and Mith, but not Tessagon, is a position held by a few austere reformist thologians. Unlike Ea-Tessagon Bilunarists they're very outspoken about their beliefs, and are roundly ignored.

Finally, Tessagon-Mith Bilunarism is what secret Monolunarists accuse others of being, because they don't put enough emphasis on the actually important moon, Ea.

And what if you're a Worm Eye cultist? You use a completely different calendar of twelve 30-day months, because of course you don't believe in all that moon stuff!