AI behaviour

[inteck]

Yeah, hang on....this will take a little while to get organized, but i'll post some of the info here for the geoscape. What i'm going to put here should allready be known, with the exception of one or two items like where the intelligence and aggression flags for the various aliens are.

 

As far as alien intelligence goes, i'll have to go back and find the offset. It was right next to aggression. All I had to to was eliminate what was known in hex values and see what I had left. After that it was a matter of matching values with the stuff in the official guide....Terrorist units have the highest aggression ratings (naturally) they run, bite, attack, and shoot madly till you or they are dead. Sectoid Commanders and Ethereals have the highest I.Q. but fairly average to low aggression ratings. They don't have to have high aggression ratings for the obvious reasons.....usually they simply hide and either lob blaster bombs at you or screw your people up mentally while using their I.Q. to hide. I have'nt been able to use your editor as far testing civs go( Ive been busy...i finished correcting the reversed aliens subs in tftd with help from daishivas program) ....this would/will probably be the best way to test out and see what the aggression ratings do though as even a negative response with the civs would be useful....process of elimination.

 

As for my own comments on this, well aliens seem to have another unseen advantage over your own troops....they don't bleed to death from wounds....makes sense because they don't carry around stuff like medikits. As far as alien morale goes, yes they lose it, occasionally you will see one get scared and drop a weapon, but compared to your people the algorithm for losing morale is probably set up differently. As far as patrol nodes go....Well I didn't know that the algorithms were that advanced. This is an older game to be sure, and I don't think that the A.I. is that good. Unfortunately, this is something we may never know since Microprose and their management in their infinite wisdom didn't ever release the source code.....I mean it's been what??? over a decade now?? and this thing and its sequel still has bugs which should should have been fixed a month in to discovering them.

 

Oh well, enough complaints. Here's the first of the alien dat info, this comes from Marco's Kaisers editor so all credit goes to him. As everyone should know, it edits savegames. It also permanently edits most alien stats including civs and xcom tanks in Geoscape.exe. There are a couple of things that it doesn't edit-namely intelligence, aggression, and immunity or vulnerability to weapons I also think that one ore two thing in this table are wrong, but it gives a general idea of the attribute format. Like I mentioned I have found the I.Q. and aggression by simple process of elimination with his editor. Working with the official strategy guide and my hex editor they were easy to find.....Its going to take me some time to find my notes.....there buried. Also, it might be of interest is that the flag which tells which animation to use(muton, sectoid, civ etc.) is here (cosmetic change only....you still get penalized for shooting a civilians dressed as an aliens) You will notice the gaps between his information here.....its where the rest of the information I have mentioned is stored why he didn't put in the remainder in his editor is a mystery to me. If I remember correctly, after the flying/non-flying flag is where the next set of alien data starts.

 

geoscape.dat

 

** ALIENS **

 

39 bytes per alien

 

 

Offset 00 01 02 03 | 04 05 06 07 | 08 09 0A 0B | 0C 0D 0E 0F

---------------------------------------------------------------------------

0611A0 | | FL | TI HE EN RE | ST FI TH

0611B0 | FA LA RGA RA | UA | |

0611C0 | PSK PST BRV | | | FL TI

...

 

v1.2 0611A0

v1.3 0621A0

v1.4 05CB53

 

FL: Flying - 00 false

01 true

 

TI: Time Units

HE: Health

EN: Energy

RE: Reactions

ST: Strength

FI: (Firing Accuracy) * 2

TH: Throwing Accuracy

BRV: 11-(Bravery/10)

 

FA: (Front Armour) * 2

LA: (Left Armour) * 2

RGA: (Right Armour) * 2

RA: (Rear Armour) * 2

UA: (Under Armour) * 2

 

PSK: Psi-Skill

PST: Psi-Strength

 

 

I'll post what little I have when I unbury my notes.

[NKF]

If I'm not mistaken, there's no predetermined patrol routes. It's more of "walk to this node. When you get there, randomly select the next nearest node and walk there. Repeat."

 

- NKF

[BladeFireLight]

If I'm not mistaken, there's no predetermined patrol routes. It's more of "walk to this node. When you get there, randomly select the next nearest node and walk there. Repeat."

 

This is true. What route is chosen is limited to what the node at the other end will allow

 

Also, it might be of interest is that the flag which tells which animation to use(muton, sectoid, civ etc.) is here (cosmetic change only....you still get penalized for shooting a civilians dressed as an aliens)

 

Only partley true. The value of the loyalty stat determins how your score is effected when the unit is killed. It also effects weather there is a enemy sighted box in tactical and who the unit shoots at. I belive it's 0 = xcom 1 = alien 2 = civilian. set it to 3 and it's jut like Alien, execpth they are hostil to the first Alien team.

 

The Skin flag does effect the natual weapon on a unit. Changing an unarmed aquatoid to a Deep one will get you killed by the spiting attack. Tanks and other 4 square units are another story as they use a spacific stat for its weapons.

 

As for the AI. Back in 1995 the Galop brothers were intervied by some E-zine I used to get (a CD based Magazine that is no nonger in circulation) They talked about how the AI works.

 

Basicly units randomly follow predefinded routs in search of targes. Then an enemy is poted it reacts acrding to it's agressinon setting (basicly how likely they are to attack or move. the higher the more likely they will stand and fight with all there time units) then there was a number of turns tha unit would remember it it had spoted a unit and know where it is. (this is higher at higer levels and techicly cheeting) this is the Inteligent stat. Level also effects how far alines see. at the highest level they will see farther then xcom units by about 5 squars and know there location for 5 turns

 

PSI works diferently, Alien units can chose to use PSI, and they do not have to have a clue were units are located.. I would chalk this up to 'sensing' your mental presence but not being able to translate this to phisical location. This is why the week minded rookie you left in the triton keeps getting taken over. (they do tend to targed the weekest first)

 

Morale does not effect the AI. Basicly at the begining of each trun all units make a Morale check (ala D&D) if they fail they panic (lose there move, drop wapon and run), or if they Criticaly fail they go Bizerk. If they pass then it goes on to the patrol or attack based on what they see (or saw in the last few turns)

 

Oh and Aliens do take critical woonds and do bleed to death.. this is rare as we usualy dont let them get a chace to bleed long , but it does happen.

 

-Blade FireLight

[inteck]

So the little buggers actually do bleed to death??? I'm kind of suprised by this revelation, it must be really rare as I have never seen it. They must calculate the wounds differently than the normal XCom troops that get wounded all the time. I always thought of aliens insides sort of like self sealing tires you shoot em' the damage is there , but they seal up and don't loose any life blood. Usually I experiment on the Mutons who can take a heavy plasma blast or two and are still standing afterward. I usually mind control them and then look at the stats after the plasma hits just to see whats going on and they never seem to recieve a critical wound......doesn't mean they don't, just means its a rarity to see.

 

I figured the aliens and civs had flags as to which side they belonged to, but I can't find my notes-and I don't remember if I ever rooted out where this particular flag is located at. At the time, you couldn't arm civs anyway so it really didn't make much difference.....They just ran around like chickens with their heads cut off and basically got in the way. With bomb blokes civ arming program these flags along with the info you posted could/can make for an incredibly interesting terror site mission.....STILL can't find my notes i'm beggining to wonder if I didn't chunk them in the garbage by accident when I moved last year <sigh>, you wouldn't happen to have the offsets for the loyalty values there BladeFireLight???

[NKF]

unitpos.dat

 

Each entry is 14 bytes long. If we count the first byte from 1, then the loyalty flag is in byte 10. Or, if you're like me and start with 0, it'll be in 9.

 

Values normally used are 0, 1 and 2. With 0 being X-Com, 1 as the aliens and 2 as civilians. (this value is not remembered anywhere else, so this tends to lead to the problem where civilians get turned into aliens after recovering from mind control).

 

- NKF

[Zombie]

Oh and Aliens do take critical wonds and do bleed to death.. this is rare as we usualy dont let them get a cha[n]ce to bleed long , but it does happen.

This event isn't that rare. Anyone that frequently uses a Mind Probe on the aliens after shooting them can expect to see maybe one critically wounded alien per mission (this depends on the weapon of course). Inflicting a critical (or fatal) wound on an alien depends on three major factors:

1) Armor. The more armor the alien has, the greater the chance of it happening.

2) Health. The more health...

3) Weapon strength. Lower weapon strengths often equate to more fatal wounds being inflicted.

 

Sectoids have the lowest Health rating and almost no armor. Rarely do I see a critical wound on one of these critters. Normally, any weapon strength will mow them down rather easily. Mutons, on the other hand, have a huge health rating of 125 (on beginner). Couple this with a higher-than-average armor rating, and you have a recipe for frequent fatal wounds - even with a Heavy Plasma.

 

I know the living terrorists (like Reapers, Chryssalids, Silacoids and Celatids) can get fatal wounds. Has anyone noticed a robot (Sectopod or Cyberdisc) with a fatal wound?

[BladeFireLight]

I know it happens.. I just said they dont usualy get to bleed to death. If one soldier cant take them down the next one finishes them off

 

-Blade FireLight

[Bomb Bloke]

Phew, this thread's gone off and left me...

 

However, even if you were able to lift the "fog of war" through xcomutil, the results might not be too helpful. Say you take an aliens inital position reading at the end of X-COM turn, then take a position reading at the beginning of X-COM's next turn. Most of the time, aliens move around but then return back to their original starting point (and orientation, may I add).

 

There must be some sort of memory concerning movement, in order for the motion scanner to work... Or maybe not. I don't know if that information would get saved to disk, because I don't think it needs to be. Nor do I know how complete this information would be.

 

Bomb Bloke, I was joking in those last statements.

 

I know a joke when I see one.

 

As for my own comments on this, well aliens seem to have another unseen advantage over your own troops....they don't bleed to death from wounds....

 

Yes they do.

 

Also, it might be of interest is that the flag which tells which animation to use(muton, sectoid, civ etc.) is here (cosmetic change only....you still get penalized for shooting a civilians dressed as an aliens)

Only partley true. The value of the loyalty stat determins how your score is effected when the unit is killed. It also effects weather there is a enemy sighted box in tactical and who the unit shoots at. I belive it's 0 = xcom 1 = alien 2 = civilian. set it to 3 and it's jut like Alien, execpth they are hostil to the first Alien team.

The graphics of a unit are entirely determined by the type of unit. You can give a sectoid the attributes of a tank, and even make it a four segment unit, but it's still a sectoid.

 

Also, whenever you kill a civilian/alien/trooper/tank, it gets scored the moment it happens, as opposed to at the end of the game. If you change a civilian to an alien loyalty, I believe you will then get scored as though it was an alien when it dies - making it a good idea to mind control civilians.

[Zombie]

If you change a civilian to an alien loyalty, I believe you will then get scored as though it was an alien when it dies - making it a good idea to mind control civilians.

That is exactly right. If you mind control a civilian, he/she initially is X-COM, but there after is considered alien. Every round after that, the civilian shows up as alien, and you must kill it in order to finish the mission. I haven't checked the points gained by killing a civilian recently, but if my memory serves, it's something like 10 points (same as a Sectoid Soldier).

 

That's a good point about the Motion Scanner, Bomb Bloke. It might be possible that when the Motion Scanner is called upon, it just checks whether that alien moved during that round, and overall, how much (a qualitative check). I doubt it actually reads an aliens actual movement "file" (if it has one), for a quantitative determination on position and speed (TU used in movement) throughout that round.

[Danial]

I haven't checked the points gained by killing a civilian recently, but if my memory serves, it's something like 10 points (same as a Sectoid Soldier).

That's not very good considering you get 30pts for saving them

[Zombie]

In the interest of accuracy, I decided to quicky recheck the points for killing an "alien" civilian. Turns out, my initial calculations were off a bit (forgot a dead Cyberdisc nets 20 points). Anyhow, you will get NO points (0) for killing an "alien" civilian. So therefore, it is in X-COMs best interest to save the civilians, instead of Mind Controlling them and killing the new "alien"!

[NKF]

It's harder to save a true civilian, but you can be more wreckless around a turned civilian and not get negative points for accidents. You just don't get the positive points either. But that's just the price you pay.

 

I think the motion scanner simply does a check of the max and current TUs of the units in the scanning area. It then picks the size of the unit blip depending on how many TUs have been spent. The more spent, the larger the blip, obviously.

 

But that's just a guess, as yes indeed, how far you've moved in any given turn isn't saved.

 

- NKF