X@COM

There's finally something new worth a video: sound effects! Hear footsteps, guns firing, shooting through windows, blasting down walls, a stompy colossus wrecking houses, and finally the almighty blaster launcher.


The video doesn't include all the new sounds (by far)--for that you can play with the R9 sandbox (when it's available).

The weapons and explosions you hear are quick placeholders I put together for testing, but footsteps, destruction, and impacts are about where I want them to be besides still needing to be expanded. Right now there are 372 sound effects that fall under the above types, with still more categories to be added.

Sound effect volume is based on distance from the nearest unit under your control (and the inherent range of the sound itself), but most of the action takes place up close so you won't really notice it here.

*so-called because you've played Cataclysm and are now dead :)

I've done a few stealth releases in the past several days, mostly little fixes and tweaks to the scenario, so we're actually up to R7.3 now. Here's a rundown of what changed in Cataclysm:

• Unarmed civilians will also take weapons you offer them (originally only armed civilians would swap for better)
• Second evac zone always different from the first
• Police now talk, and eventually receive orders to leave their station and do what they can to help civilians evacuate
• Suicide bomber detonation text uses proper actor (bomber detonates, not their intended target...)
• Mission results correctly shows number of scrolls read
• Fixed actor reference for one of Rev. Jones' lines
• Fixed a few typos

There were a few other gameplay issues I found, which you can read about in the changelog. (The updates do fix a pair of pretty serious bugs, so if you're still playing R7, I highly suggest making sure you have the latest version.)

For those of you only following the project and not actually playing yet, I've uploaded a new video showing a quick overview of the new and old game elements. As usual, YouTube manages to ruin the clarity with overzealous mp4 compression, so HD + fullscreen are essential (and even then the quality leaves much to be desired).



In addition to the tips provided on release, here are some more hints and strategies to help you survive long enough to evacuate:

• Some items may have unexpectedly useful melee attacks.
• Alien enemies are spawned entirely from the necromass, and both it and all of the spawned units except for one are weak against fire. They're also very slow. If you can get your hands on some "fire"-power (there are several sources), you'll be nigh invincible... until your ammo runs dry.
• If you see a growing Necrospore Shell or Bulge and have something with which to destroy it, by all means do so immediately, because what it hatches will no doubt be a fairly big problem.
• Avoid wading through the necrospores--it slows you down.
• If you can manage to persuade the drug dealer to give you some cocaine (guns being the best form of persuasion), it works pretty well on zombies...
• If you can get hold of a bible, they have a chance of smiting zombies when you whack them over the head.
• You should of course immediately gather your family first--they'll be your first rescues, and they all have rudimentary armament, which is better than what you've got, so they can at least shield you if absolutely necessary.
• Always always grab the sledgehammer in the garage. It's your primary weapon until you can find something in another house/building. Also make sure it goes to your strongest soldier--strength = damage for the sledgehammer. Notice you have two rookies and two sergeants--the latter are generally going to be stronger, and better at just about everything else, too.
• House garages always contain one common household tool that doubles as a weapon.
• Remove guns from cases and swords from stands using the undocumented manipulate ('n') command. (They're quite uncommon, but you may find one.)
• If you see a chryssalid, RUN. The only way you can hope to defeat one is with some fairly heavy explosives. Conventional arms aren't effective enough since chryssalids have thick armor and can close on you way too quickly.
• If you spot some useful assets, don't think "Oh, I'll just go around this other building then circle back and get them", IMMEDIATELY go straight for them. Things change fast, and there a lot of unknowns. There may be no later, so if you really them now...
• Food and drink are good for restoring stamina, which you may run low on if you run around a lot (which you probably will)--drinking an espresso and continuing your sprint is better than having to take a breather and wait for those zombies to catch up to you!
• Flares can be useful later on when the power starts failing and street lights start flickering off. Even worse than fighting a horde of zombies is fighting a horde of zombies in the dark where you can't see them until they're almost on your position. Remember to light (use) the flares before throwing them! (These are standard flares, not the X-COM electro-flare variety).

A few screenshots from Cataclysm runs:

Here I've herded herded my civilians together for a final push through the zombies--the necromass decided to spread all over the evacuation zone to the west... This is right before I discover that unarmed civilians won't take weapons you want to give them (fixed in R7.3)... Fortunately the good reverend hooked us up with molotovs and I had found a shotgun elsewhere. (You can actually see a bit of this exact scene in the video.)

Seeking refuge by the church altar while Rev. Jones does his thing. No one gets into this church without permission from his shotgun!

A scene I captured while checking on the game as it ran on autopilot just before R7 release. Man are they screwed.

Field Reports

In the past few days, players on Bay 12 have been sharing some of their experiences as they try to escape the alien-induced apocalypse. Read about their exploits here (post order):

Draxis: "My team was leading a large group of civilians out of a zombie-infested area, when a zombie runs up and attacks my lead man. He smashes down the zombie with a sledgehammer, but an alien emerges from the corpse and strikes him down. He drops the unstable compound he is carrying, and it explodes, wiping out my whole team. This causes the similar compounds carried by the rest of my team--we got them out of an abandoned laboratory, and were using them as grenades--to explode as well, killing most of the civilians following us and leveling a block and a half."

Lesson: Spread out when carrying dangerous chemicals.

Crazy Cow: "I explore the city, finding nothing but a Starbucks until I come across a drughouse in the corner. The gang is dead, but it's filled with cocaine and Glocks. I set up shop waiting for the order to evac, and decide to try one of these cocaine blocks. Toshio Tanida promptly eats the entire block and falls into a coma. *facedesk*"

Lesson: Don't try cocaine while fleeing from zombies. Having a medi-kit handy might make it okay, though ;)

Orb: "I had a grenadier with unstable compounds ready to give fiery death to the necrospores. However, Doctor Faust thought it was a great idea to shoot him instead of the zombie, and proceed to have him, the Zombies, Doctor Faust + Pet, and the laboratory destroyed. Thankfully, the other two members of my team were elsewhere (1st death was due to throwing an unstable compound instead of an Anti-Necro 'nade at close range...never making that mistake again.)."

Lesson: Doctor Faust is a bad shot (he really is).

1freeman: "Just had my first 'successful' run on cataclysm, I managed to find the good doctor's lab early on which allowed me to stock up on unstable compounds and a pair of useful companions. I made my way to the northwestern quadrant and found a certain pick-wielding civilian who also joined me, then the good doctor got a little trigger happy and shot one of my guys with the explosives who died and set off a chain reaction killing another agent and most of the civvies including little Timmy and the doctor himself. The survivors then grabbed the doctor's gun and the sledgehammer, the only weapons I had left. I desperately fought off the zombie horde and just when all hope was lost I received a message from HQ informing me of the new evac zone which miraculously was nearby. Then a crystallid pops out of a zombie like a demonic jack-in-the-box, and kills the guy with the gun. I send my last agent to sprint to the evac site, leaving most of the civilians behind and with my points in the negative but hey I survived the !!FUN!! and came out a victor."

Lesson: Death and destruction is enjoyable, even when it's your own squad.

Crazy Cow: "I sat myself in the police station, used my sledgehammer to knock out the floor tiles around the stairs, blew out the far wall, and shot as many zombies as I could. After a while my limited ammunition ran out, and I sat around lobbing unstable compounds at the necrospores if they came close enough. An unnatural shriek pierces the air, and I don't give a fuck because chryssalids can't fly. The bugger paths up to me, which I found strange, so I just stared at it for a bit. Then... the chryssalid tears through the shelves lining the wall and attacks my weaponless soldiers, killing two and zombifying one before my turn rolls around. >_>"

Lesson: Don't challenge a chryssalid to staring contest. It will tear through the shelves and kill you all ;)

kingfisher1112: "A necro lord fucked up my shit, and a homeless guy killed it. Also, 'Package arriving in 5 minutes'? Is it weapons/supplies?" [he was posting while playing--this point was laugh-inducing for anyone in the know] "So. I played again. I played and I got some pretty good weapons. Rescued some civvies. Then A MOTHERFUCKING NUKE LANDED WHY ISN'T THIS IN REGULAR XCOM?"

Lesson: X@COM just gets more and more fun.

Kyzrati (while playtesting): "Down to one man, obliteration by tactical nuke imminent, I'll just hide in this house here... Miraculously SURVIVE the nuke (it happens) while pretty much everything around me is leveled (the toilet from nearby remains!). 'Wow, this is great, now I can walk around the level and see what's going on *after* the nuke!' Apparently I wasn't the only one to survive: Ten steps later a gang member walks out of the smoke at almost point blank range and shoots me dead with his pistol..."

Lesson: Murphy's law of X@COM: If you survive the nuke, it must be because you deserve some other ironic death.

Kyzrati (still playtesting): "Looking into the drug dealer's house from afar I see that everyone on the first floor is already dead. Must've been hit by a wave of zombies. Guess I'll just go pick up some free weapons. Sure enough, the first floor is littered with corpses both human and undead, and GUNS, yay! So I grab a nice pistol for myself by the stairs. Hm, should check upstairs and see if anyone's left... Ah ha, one last gang member looking out the window with his back to me. Well, I'll just shoot... *click*. DAMNIT, the pistol I grabbed is out of ammo. (That must've been some firefight downstairs.) Oh well, I'll just whack him in the back of the head with my pistol then! Sneak up behind him... *wham*, he takes the blow but doesn't go down, instead spinning around to shoot my guy in the face with reaction fire... [Several minutes later another unarmed soldier dodges into that same house, fleeing a group of zombies.] Nowhere to hide from all these zombies but upstairs... He heads up stairs to find there's already a zombie up there facing off with that same gang member. He has plenty of time and is standing behind the zombie, but decides to wait and hope that dude gets mauled. Unfortunately he blows the zombie away with his pistol. My turn. Walk up and pick up the sledgehammer my earlier friend dropped from his backpack. *WHAM* The hit doesn't kill him, but knocks him right out the window he was standing in front of... right into the middle of the zombies that had chased me up to the house earlier."

Lesson: Revenge is sweet.

That's enough fun for one post. The next one will be about modding X@COM. I've also updated the FAQ with a new section that addresses some questions which have come up multiple times in the past months.

"Nine meters. Seven. Six."
"That can't be! That's inside the room!"

Yes, this will probably happen to you, too.

Actually, the short range of X-COM motion scanners makes it all that much more likely. Of course, with about five seconds of modding you could expand their effect to cover the entire map. Not that you'd want to, but it's *very* easy now that they're a part of the special abilities system, too.

Since returning from vacation I've been pushing forward on that same system, adding yet more triggers and effects, most notably object spawning which means triggers can now create terrain, items, and units. But everything so far is internal stuff that doesn't make for interesting posts with something visual to show for it, so I sidetracked myself in order to bring you a simple implementation of the motion scanner interface.

Motion scanners are nice, and you are definitely going to want one on the new scenario that will come with the next release, but that's all I'll say about that for now...

Check out this video showing the scanner in action as it gets some relatively heavy use in the urban Exodus map: A spotter locates an enemy hiding in a building and his buddy blows through the wall with his gatling laser. Then we put up a smoke screen before moving into an open area, and find another building swarming with aliens and send a rocket through the door...



Now back to chipping away at the trigger/effect list.

It's been a surprisingly long time since the last post. Sorry about that. Not that nothing's been happening over here, but I prefer having something concrete to show with every post. I'm still chipping away at the todo list, but the current stage of development involves spreading out into quite a few new areas of the game code, certainly much more time-consuming than banging out simple and well-documented game mechanics!

Plus, I don't want to screw something up now in the core program that'll become a source of endless headaches later.

Recent developments have been all about paving the way for a new interface. The HUD is still waiting on the sidelines, mostly because I have yet to decide what exactly it should contain and how to organize it all. Instead I'm testing the system by implementing a simple inventory window. I know your soldiers are getting antsy about the fact that they just *know* they have more ammo in their backpack, but, um... forgot how to get it :)

Well, now they'll finally be able to stock a few extra grenades and missiles, and do it in style!



Okay, so it doesn't look like much yet, but look again... it's alive!



The system is capable of far more than you see here. This sample is powered by a simple, generic window-drawing script; the interface animations are completely exposed in text files, similar to the weapon particle effects. So, just as you see weapons producing a range of snazzy effects, windows can do all that and more, and can be tweaked, or even rewritten, from the text files. (For those interested in the dev aspect, the system is very basic but powerful nonetheless: every visual component of the engine (window/control/button/etc) inherits from the same console base class, and every single one comes with its own lightweight particle engine--I LOVE PARTICLES! Besides making it not too difficult to implement good-looking effects, giving every object its own particle engine also makes control/manipulation fairly easy: even windows containing complex interconnected animations can be manipulated piecemeal and the flow seems to work almost automagically!)

In the game you won't have to watch entire windows be redrawn every time they're accessed--the way I have it now only the content portion will be redrawn after seeing the complete animation once (per run).

In its current state, the inventory screen should already be pretty informative and usable, showing TU costs, weight/encumbrance changes, highlighting valid/invalid targets for moving items or reloading, and telling you exactly why you can't do something, etc. It'll be expanded later on with additional functionality like the ability to define and apply set loadouts/equipment kits, and direct manipulation of other units' inventories (tanks that hold things, or those with modular weapons that could be swapped out by an engineer?).

In terms of control, the inventory is 100% controllable by obvious and intuitive keyboard commands. I used the mouse in the video so you could better understand what the heck was going on...

I originally thought the inventory interface would be a bit more graphical, but that wouldn't be as compatible with the new arbitrary inventory slot system. Armor and inventory slots have now been completely exposed in the text files, enabling simple creation of different kinds of armor which provide unique amounts of storage space and locations. Races are also connected to the slot system (also through the text files), so different races can specify different natural slots (which combine with armor slots to give a unit's total inventory layout). As each unit keeps track of its own available inventory slots, eventually adding the possibility of losing a limb won't be too much trouble (it'll still require a more specific body part list, though, which would also be compared against armor to make sure a given armor is usable by a certain unit at all).

Soon/next I want to finally integrate some sound effects into the particle engines to see how that should work with the animations. Hopefully those windows will be bleeping, blooping, whishing, and whooshing in no time. The audio engine is already in place, I just have yet to put together the resources and add ways for particles to trigger sounds.

The number of new features has hit critical mass, so time for another release. See the files page for a link.

As detailed in the last post, large units have been added. You get a tank this time, too. Admittedly not an impressive one, but anything will help against your new enemies, the alien "terror units." For now only large terror units are included; normal-sized thralls will come in a future version.

Terrain smashing is now implemented. Talk about putting the gravity system to the test... Giant units plowing through buildings, heavily-armored X-Com units dropping through weak house roofs in style, tanks mowing down fences... Everything went smoothly except the house filled with stuff getting bulldozed by a house-sized alien--he really helped me fix all the rare bugs :)

Now you can jump through windows without bothering to shoot them out first! By default, "smash movement" is *not* active--you can toggle it on a per-unit basis using the 'h' key. (This is so that the pathfinder knows what kind of path to take.)

Stronger units can smash almost anything, while most rookie soldiers can't get through much more than glass, shrubbery, and other weak obstacles, though stronger soldiers can eventually push through fences, thick hedges and weak walls, or even smash chairs and some other furniture as they move. Later on, some armor and equipped weapons will probably improve a soldier's ability to smash things. Sledgehammer, anyone?

Essential for large units, built-in weapon modules are now operational. The system is very expandable and can later be used to enable units to accept multiple modules, even non-weapon modules with special effects.

Melee attacks (m/M) are now possible, too. In fact, you can use any item to perform a melee attack. Farm level? Grab a pitch fork and stab the little bastards! (Warning: May not work on big bastards.) I divided melee damage into three types: bludgeoning, slashing, and piercing (others can be used or more added easily). Melee attacks can of course do non-melee kinds of damage, like the stun rod.

Bludgeoning damage may also knock targets backward depending on relative strength and item mass. Whack an alien right through a window and have him fall to his death! Or, if you're strong enough, push him right through a wall...

Melee attacks do not currently harm terrain (as in the original), though that can easily be changed by modifying the materials.xt file.

Knockbacks and terrain smashing are both optional (though in the demo there's no button to toggle them); those and the many other optional settings will eventually be accessible through a config file.

About the new demo:

• Most of the large units are what you'd expect from X-COM: UFO Defense, but I did throw in the chance of one 3x3 unit. Here's hoping you don't get mauled by a Mega Reaper. (Murphy's Law says you will.) And if you see some toppled houses and trampled hedges while you're scouting around... well, let's just say you're probably not safe :)
• Explosives are quite effective against large units since *all* sections take damage separately.
• For those who have previously checked out the bunker, there's a couple new toys inside :)
• See the changelog for a full list of changes (some commands have changed)

I also put together a quick demo video showing large units. To speed things up, I'm controlling the aliens in a mock battle. In retrospect, there should've been more wanton destruction :)



There will probably only be one more tech demo release soon (reaction fire), then a rather long gap before the first alpha version.

Now what are you waiting for?! Go stun yourself an alien!

You read the title...

You've played X-COM before...

You know exactly what I'm talking about...

Let's flex our new-found throwing muscles and put the hurt on an unsuspecting alien emerging from his craft...


(Not a great video, but maybe throwing the electro-flare and smoke grenade helps make up for it? :)

So as you can see, proximity grenades work, as do many other kinds of grenade explosions. Any item with an attached "throwing explosion" also has a "grenade use" setting. Besides the standard/expected PRIME and PROXIMITY settings, I added support for these:

• IMPACT: Explodes immediately on impact if thrown (instead of waiting until the end of the turn like a normal grenade primed to 0).
• VOLATILE: Like IMPACT, but will also explode if it falls and hits the ground.
• REMOTE: Thrown/dropped and set off remotely/manually with a detonator. This is not yet fully supported, since there is no way to create detonators, but it seems like a frequently requested option in X-COM remakes, so it could eventually be added (not going to bother in the short-term, though).

None of these were in the original X-COM, but they could later be used to create interesting items.

In other news, I've decided to join this year's ARRP with X@COM! Everybody's doing it :) Seriously, if I wait until I'm far enough along to make the game semi-playable and good enough to get through my perfectionism filter, it could be many months away, and this being a project with a fairly clearly defined initial goal, it's not like I've got a ton of secrets to hide when it comes to gameplay. The unique components are a ways down the road, anyway.

I may as well let people try the game out early, so I'll be releasing occasional tech demos beginning September 18th, 2011. Tech demo releases probably won't be all that frequent (compared to playable releases, which will be updated quite often when they start coming), but I may as well throw something out there just to be a part of ARRP.

So what can you expect? It'll no doubt come with a big fat disclaimer, but hey, it's a sandbox tech demo, after all. Content-wise, you'll basically be getting the latest version I'm using to debug/code the game, so it'll include all the features you've read about in posts and seen in the videos. Unfortunately AI will be nonexistent, so you'll have to settle for blowing up terrain and static units. Anyone interested could, however, play with the data files (text) and create/modify just about any object... I'm still undecided on whether to leave debug output/interface features in the demo.

As usual, opinions are welcome!

Here's a quick video of guided weapons in action:


I was going to add grenade priming today, but the X-COM system seems like it may be incompatible with X@COM. For a breakdown of the original timing system, see here.

I like the original system. Despite not being intuitive and obvious at first, it's fair and works pretty well. The problem is, it only really works when you have two sides (X-COM + aliens), no more (civilians are ignored for grenade timing purposes). But X@COM supports an unlimited number of factions (teams on a given level) so you can potentially have more groups than just X-COM and aliens.

Not sure what to do about this yet. Checking grenade timers only at the beginning of a new round is obviously unfair, and using the thrower's turn as a reference may not be flexible (or fair) enough in some cases. I'll have to think on it some more, but thought I'd throw it out there to see what others think.

Maybe a faction's grenades can only go off at the beginning or end of their own turn. Thus priming to 0 will explode as soon as you end your turn, 1 will go off just before your next turn, 2 = after your next turn, 3 = beginning of the turn after that. Seems confusing, though really you don't prime for much other than 0 or 1, maybe 2...

The main thing this leaves out is the ability to have a grenade go off between other factions' turns
but that doesn't seem possible to work out, or even necessary actually. And maybe I've come up with the answer myself while writing this post :)

Quick addition: light-emitting items. It was only a few lines of code, since light sources were already attachable to any other object--it was just a matter of detecting and updating light-equipped items. Below is an unexciting shot of an electro-flare (seen top-center, on the ground, as a squad moves in on the area).

The last set of YouTube videos were pretty fuzzy, small, and unimpressive-looking, so I've made a new one that includes most of the same material, but in a larger format and zoomed. Check out the smoke-filled incendiary extravaganza below (you can use HD/fullscreen):

There's no sound yet, so I added some music instead. Not all that X-COMish, but it's the first thing I thought of. The game itself won't really feature much in the way of music--ambient sound/music at the most (like the original)--there'll be an emphasis on sound effects (with lots of interface sfx).

By popular request, here's a screenshot showing damage distribution from a large rocket, as impeded by brick walls:
(Okay, it was just Creepy who mentioned it, but seeing as how few people know about X@COM, he does make up a good percentage of the readership :)

I've also added a page containing the full changelog, which will be updated with every new version (whether internal or released). See the link at the top of the blog.

Probably going to work on parabolic trajectories next, to enable throwing and the potential for weapons like mortars (obviously not something to be included in the initial core game, but they could appear in a later mod).

Ready to roast some aliens? The newest additions are all about various ways to turn up the heat.

First, explosions of any kind can now be attached to props and entities, so UFO power sources, cyberdiscs and more can now explode. How to do a suicide run on a UFO:


Taking out a cyberdisc (2x2 units aren't yet implemented, but it blows up just the same):


Incendiary weapons now create fire which ignites terrain and entities. Here's a rocket launcher firing incendiary rockets, after which you can see the fire spread a little (it would spread much more in a wheat field). Burned terrain will produce varying amounts of smoke/dust based on its composition (also occurs when destroyed or when props fall from heights and smash into the ground).


Although not as effective as incendiary ammo for the job, HE weapons may of course cause some small fires, too:


Fire is naturally useful as a makeshift light source:


Smoke grenades make a much denser, longer-lasting patch of smoke (throwing not yet implemented--this is shot from a weapon):


Smoke affects FOV (kinda the point):


And for the grand finale, lets burn that house to the ground, just because we can (and then blow it up afterwards, because that's fun, too :)


On a side note, even though the videos were already cropped down to nothing, YouTube still  felt compelled to compress them to nothing. Maybe next time I'll just record the entire window in HD instead. (I wish I could use screenshots instead, but the latest updates are best shown in videos...)

So here are the latest major additions:

• Exploding Props & Entities
• Effects of incendiary weapons/explosions
• Fire burning/propagation and light emission
• Entities catch fire and burn
• Smoke results from fire and some weapon effects
• Smoke affects FOV and stuns units
• Materials can release varying degrees of smoke/dust when burned or destroyed

Current state of the near-term TODO list:

• Light-emitting items
• Variable animation speed
• Throwing
• Sound effects
• 2x2 units
• Reaction fire

Talk about an unexpected diversion!

With explosion damage calculations out of the way, next up was figuring out how to best animate them. One moment I'm scratching out some possibilities, then I jot down an innocuous little note along the lines of "need a particle system?" and ended up resting on the idea.

Next time back at my desk I'm writing a fully-featured particle engine, and the next and the next...

Never written one of these things before so it was a somewhat slow start, but once the pieces started coming together it became obvious this was the way to go. Particle engines are awesome!

I've opted for the heavily parameterized single-class model. Overall it's a pretty versatile system:

• Particles make use of a wide range of dynamic variables:
• Age can be a constant, random, or dependent on distance from a point
• Speed can be static, constant, random, or follow a linear or sine function
• ASCII characters, if used, can be static, based on direction, or sourced from an animated list or a random set
  
• Color blending options (foreground/background) are more or less the same list available in libtcod: 
• Add
• Subtract
• Multiply
• Scale
• Linear Interpolation
• Add Alpha
• Screen
• Color Dodge
• Color Burn
• Overlay
• Any color can be dynamic, since particles are able to mix multiple colors based on their current age or speed using 10 or so kinds of linear/sine functions
• Particles can also be emitters themselves, spawning other particles based on various triggers, rates, randomness, direction information, etc, so it's pretty easy to chain together complex effects
• All these parameters are loaded from a text file, and attaching a particle effect to a weapon/item is as easy as writing its name in the item text file.

Internally, projectiles and explosion results are now a kind of particle, since integrating them into the system seems like an obvious choice.

Particle engines are pretty powerful, and I still don't know all the tricks to using this one, but in the coding process I designed several test effects and made a video where you can see them in action. Everything's kinda small at first, but it'll zoom in; and going fullscreen will help a lot since I recorded it in large format. (Note: This was my first-ever attempt at recording a video. Next time I'll try to keep the mic out of my mouth, promise!)