Understanding Firaxis's programmers.

[Spec]

Posted by Nathan on another forum and I re-used it to make a point

As a programmer who has taken a couple classes in artificial intelligence (although my real work is in other areas), I can sympathize with Firaxis's AI design problems. Civ 3 is a complex game. How complex? Compare it with chess, which itself was a tough nut for AI design teams to crack.

In chess, there are 64 spaces on the board. In Civ 3, there can be thousands. In chess, there are six different types of pieces. In Civ 3, there are dozens of different types of units. In chess, each side makes one move at a time. In Civ 3, there can be a dozen or even several dozen choices in a given turn. In chess, the position after each move can be known in advance. In Civ 3, each individual attack has two possible winners and several possibilities for how badly damaged the winning unit will be. And in chess, players can see the whole board at once. In Civ 3, at least in the rules the human player is bound by, much remains hidden.

Further, a game like Civ 3 has a huge "rock, scissors, paper" element in which a strategy that works great against an opponent who plays one way can be awful if the other side makes different choices. I've fought wars where practically my entire army was on the front lines, sometimes leaving virtually nothing on my home island or continent. If the AI played that way and I figured it out, I could take advantage with a naval invasion before an AI knew what hit it while one AI's troops were away fighting another. We as human beings can figure out the AI’s strategies and adapt, but the AI has to stick largely to strategies that will work reasonably well against a wide range of possible opponents.

Someone (I'm not sure whether it was here or somewhere else) brought up the idea of using something along the lines of genetic algorithms to help the AI adapt. But while genetic algorithms might be useful in refining basic strategies, they lack the "big picture" analysis capability of the human mind. Someone has to come up with the root strategies, and has to code those strategies in such a way that the AI can make use of them (probably losing something in the translation).

Here's a challenge for anyone who wants to call Firaxis's AI designers less than competent. Come up with a rule set that defines your strategy, and try playing a few games where you're only allowed to do things that follow that rule set. NO EXCEPTIONS, EVER. Make sure your rule set can handle both good and bad starting positions on a variety of map types. And if you succeed at that, look for ways you could beat your strategy if an AI adopted it.

And if you succeed at that, ask yourself whether human players would get mad at the game if the AI followed your strategy. If you have to engage in dirty tricks that lots of human players would object to having AIs use against them, you don't have a viable core for an AI design. After all, the ultimate goal is to sell games, not to have the AI win them. (On Deity, AIs could mop the floor with a human player just by engaging in an all-out war early on, but how many players would put up with the AI using its advantages that way?)

If you can get past that last test too, you probably ought to ask Firaxis for a job. Otherwise, you're asking Firaxis to do something you have no particular reason to believe is possible.

I do think subtlety is important in designing an AI's advantages. The AI's advantages need to feel "honest" to the player rather than like "cheating" - sort of like when my father used to spot me a piece in chess when I was a kid to make our games relatively even. The real problems seem to come when the AI's "cheating" digs into the realism too much - ridiculously lopsided valuing of potential trades, or getting techs ridiculously quickly, for example. But the idea of an AI trying to take on a top human player without significant advantages is all but unthinkable.

One last thing: more powerful computers can only do so much. Double the power of the computer and you won't even have the computer able to look one turn farther ahead unless it dismisses an awful lot of possibilities without even considering them. (In practice, the computer will look more than one turn farther ahead along the paths it considers important while not looking any farther ahead at all along paths it considers less unimportant.) In a game as complex as Civ 3, AIs HAVE to rely first and foremost on core strategies provided by human beings and only secondarily on lookahead-based analyses that can be improved (if not necessarily a whole lot) by adding processing power.

I very much hope Firaxis keeps working to improve the Civ 3 AI. But anyone who expects an AI that can even stay within shouting distance of a top human player in a game as complex as Civ 3 without a lot of advantages is being unrealistic.

Nathan

[Thrawn05]

int main()
{

//Insert Civ stuff here

return (1/0); //We want to crash the program
}



Hehe, actualy I agree. It hard enough trying to make a pathfinding AI. So far, the only AI i've seen in detail is the AI used in AL|ENS v. Predator. Lots of Structs and #define statements.

[Spec]

Originally posted by Thrawn05
int main()
{

//Insert Civ stuff here

return (1/0); //We want to crash the program
}

Spec.

[petey]

A good point and a valid argument against those who keep bashing how the AI plays without bothering to give any concrete examples of what they'd do better. They've put out a very good product here and programming AI is a tough thing to do, especially if you want to have a complex game that handles a variety of instances.

On a side note, I'd like to add that the AI sucks and the people at Firaxis can't program worth a damn.

[Inverse Icarus]

it appears as if firaxis adopted this diety code:

int main()
{

char outcome[20];

moverandomly();

outcome = talktohuman();

if (outcome == "war")
{
cheat();
attack();
}
else
{
cheat();
moveunits(humanterritory);
attackanyway();
}
return(0);
}

[Locus]

Great post. However, this is exactly why everyone wants Multi-player!

[Inverse Icarus]

exactly.

any AI short of the matrix will fall before a good human contender... and perhaps even that would crumble.

[Thrawn05]

Originally posted by Locus
Great post. However, this is exactly why everyone wants Multi-player!

int main()
{
unsigned short Players[16];
PlayerTurn();
if (PlayerTurn(True))
{
LagCode();
}
else
{
MoreLagCode();
}

If(Player == Ming)
{
GodCode();
}
else
{
TankKillerSpearmen();
}

return 0;
}

[Locus]

Imagine marathon weekend Civ tournaments with 16 players on a huge map!!!

[Sze]

The AI seems to be better than Civ 2, but I'm not so sure. It's been discussed before how the game rules were altered in dozens of ways to make the AI appear smarter. If they couldn't figure out how to make the AI play smartly by the rules, they just changed the rules. Please note that this will diminish the MP experience, if MP is ever finished. I like how they don't automatically gang up on you if you're ahead or behind, but that's about the only nice thing I can say.

There are some very silly things the AI does that really makes it look dumber than it actually is. The AI will build a Forbidden Palace in its capital city. It will start building a wonder in a city that is under seige. It will send 30 workers to mine a mountain that is in its cultural borders but not in any of its city borders in the same turn. I've seen these things happen. I'm not a coder, but I imagine such checks would be fairly trivial to implement.

[Coracle]

The hell with Firaxis' programmers.

Everyone knows that Civ 2's AI made more sense than the AI of Civ 3. And we've all played both games enough to know that.

It should not take a genius programmer to know that when your civ is being seriously invaded you do NOT start a Happiness Wonder. Nor when you are at war and one of your cities was razed by the invader do you send a settler/pikeman combo wandering towards the open tiles right past twenty enemy knights. And so much more that shows me nothing other than SLOPPY RUSHED PROGRAMMING.

[asleepathewheel]

Originally posted by Locus
Great post. However, this is exactly why everyone wants Multi-player!

I don't want multiplayer. I'll let you know when I want to proxy my opinions to be included with "everyone" so as to make that an accurate statement.

[asleepathewheel]

Originally posted by Coracle
The hell with Firaxis' programmers.

Everyone knows that Civ 2's AI made more sense than the AI of Civ 3. And we've all played both games enough to know that.

It should not take a genius programmer to know that when your civ is being seriously invaded you do NOT start a Happiness Wonder. Nor when you are at war and one of your cities was razed by the invader do you send a settler/pikeman combo wandering towards the open tiles right past twenty enemy knights. And so much more that shows me nothing other than SLOPPY RUSHED PROGRAMMING.

I agree with you that the AI can do some strange things at inopportune times.

Perhaps I played a Civ2 that was different than the one you played. In the Civ2 that I played, I found that, among other things, the AI could not use caravans or spies effectively, at least no where near what a human could, would send slow streams of units that I could take apart piece by piece, never seriously threatening me and I could go on and on.

Sure, the AI in civ3 does some odd things, but really, I can't begin to compare the abiliity of the AI to that of Civ2. The challenge is much greater for me now. No more invincible howitzer rushes at the end, thank god.

If you have such a problem with Civ3 maybe you should just get over it, its been out over 5 months now. I have felt disappointed in games before, myself, but really, let it go man, let it go, enjoy life.

[nbarclay]

Originally posted by Coracle
And we've all played both games enough to know that.

All? I got my start in Civ games with the original Call to Power shortly after it came out. I bought the "Test of Time" edition of Civ 2 but never got around to installing it because the idea of having to worry about mess like which unit is supported by which town seemed like it would be more hassle than I was in a mood for. Maybe someday I'll get around to trying it out, but it's hard to imagine giving up the things that were done RIGHT in Civ 3.

Nathan

[Spec]

Originally posted by nbarclay


All? I got my start in Civ games with the original Call to Power shortly after it came out. I bought the "Test of Time" edition of Civ 2 but never got around to installing it because the idea of having to worry about mess like which unit is supported by which town seemed like it would be more hassle than I was in a mood for. Maybe someday I'll get around to trying it out, but it's hard to imagine giving up the things that were done RIGHT in Civ 3.

Nathan

Hey Nathan, I hope you dont mind I used your post from Civgame, I thought it was really good and that I could use it here to make my point.

Again thanks.

Spec.

[BillChin]

Originally posted by Spectator
Posted by Nathan on another forum and I re-used it to make a point

Civ 3 is a complex game. How complex? Compare it with chess, which itself was a tough nut for AI design teams to crack.
...

Further, a game like Civ 3 has a huge "rock, scissors, paper" element in which a strategy that works great against an opponent who plays one way can be awful if the other side makes different choices.
...
I very much hope Firaxis keeps working to improve the Civ 3 AI. But anyone who expects an AI that can even stay within shouting distance of a top human player in a game as complex as Civ 3 without a lot of advantages is being unrealistic.

Nathan

I agree and disagree. I believe Civ III is a relatively simple game especially when compared to chess. I am a novice player (only three months in). I taught my 14 year-old nephew how to play a half-decent game of Civ III in a day. He was struggling on Warlord difficulty and now can crush Regent difficulty consistently. There is little chance that a three month chess player can play a decent game, much less teach someone else. Even a great chess coach would have a hard time teaching a novice player how to play a half-decent game of chess in a day.

Looking at the number of pieces and the size of the map frames the problem in a difficult way. I prefer to look at what the computer can do easily and build upon that.

I agree with the Rock, Scissors, Paper element of Civ III. Good point.

The Civ III AI is decent. It can beat 20% of casual players. Look at the many threads from players wanting basic help. I believe with a doubling or tripling of AI resources, Firaxis could get the AI up another 20% to beat about 40% of players. Unfortunately, marketing would likely veto such a budgeting decision. Many humans do not want a better AI. They find it frustrating and makes them want to toss the CD in the garbage.

No publisher is going to sign up for higher costs and fewer customers. I believe the AI problem is primarily a matter of marketing and budgeting. With enough resources, I am sure Firaxis could come up with a good AI. Good defined as an AI that can beat 80% of casual players on an even playing field. However, the overall budget might be 50% higher (maybe 10x or 20x more for AI) and the customer base 20% smaller.

[Jason Beaudoin]

Nathan has created an incredibly well written point here, and I totally agree with him. Firaxis has done the best job they could given the time and resources they had, and I'm satisfied with what they have produced in CIV3.

I don't think we will see better computer AI for a quite some time. No AI will be comparable to a human player until software engineers are able to figure out how the human brain works, particularly how the brain uses existing knowledge to create new thoughts.

However, I do believe that once scientists have figured out the basic functions of the brain, they will be able to mimic those functions. At that point, AI will program itself, just like a baby learns basic skills just through trial and error. I think that if scientists can figure out how to make AI teach itself, even something simple, and give it a strong sense of curiosity, AI should develop the ability to store skills and then use them later for other, more complicated tasks. Without the skill to learn, AI will never be better than what we have today, because a programmer can only code so much.

[WarpStorm]

Originally posted by BillChin


I agree and disagree. I believe Civ III is a relatively simple game especially when compared to chess. I am a novice player (only three months in). I taught my 14 year-old nephew how to play a half-decent game of Civ III in a day. He was struggling on Warlord difficulty and now can crush Regent difficulty consistently. There is little chance that a three month chess player can play a decent game, much less teach someone else. Even a great chess coach would have a hard time teaching a novice player how to play a half-decent game of chess in a day.

Ah, but could your 14 year old nephew beat one of the players who regularly plays on Emperor or Diety? Compare apples to apples. The Civ AI is fairly easily exploited at all difficulty levels due to the complexity of system.

[Spiffor]

I don't think chess is more complex than Civ3, it's more a "simple-and-elegant" game, where a very basic design makes it for a great replayability. But Chess, unlike Civ3, is multiplayer since its invention. Had you a clumsy AI (some Chess video games are a joke), you'll teach you nephew to beat it in less than 2 weeks.
I'm not saying that Civ3's AI is clumsy, I consider it as the most advanced AI ever seen in an empire building game. I'm saying that it is much more complex for an AI to handle. But if your nephew was to play against a deity-beater on a MP session, you'd probably think he would need much time to play a decent game.

[WarpStorm]

Spiffor,

You said what I was trying to say, but yours came out much better.

[BillChin]

Originally posted by WarpStorm
Ah, but could your 14 year old nephew beat one of the players who regularly plays on Emperor or Diety? Compare apples to apples. The Civ AI is fairly easily exploited at all difficulty levels due to the complexity of system.

He'd have a shot due to the Rock, Paper, Scissors nature of Civ III. In a seven game series, he might win one game and maybe two if he gets some great starting positions.

My main point is that a better AI is more of a budgeting and marketing problem then a technical problem. I am confident that with enough resources, time and budget, a good AI can be delivered. Unfortunately this may increase the overall budget by 50% and cause much of the customer base to become frustrated. In my opinion, this equation of more costs and fewer customers is the biggest stumbling block to a better AI, not technical factors. People that say it can not be done with the current technology are misguided. It can be done, but at what cost, and with what approach.

My favored approach is a scripting language that lets the fan base direct the AI. Have the game randomly choose from available scripts at the start of the game. Due to the Rock, Paper, Scissors nature of Civ III, a player will lose every now and again. Good scripts will be copied and improved upon. Bad scripts will be weeded out very quickly. This Darwinism will produce a good AI. Again, good defined as one that can defeat 80% of casual players on a level playing field.

"Nothing we do is hard, we make it hard."

[Sze]

Originally posted by asleepathewheel


I agree with you that the AI can do some strange things at inopportune times.

Perhaps I played a Civ2 that was different than the one you played. In the Civ2 that I played, I found that, among other things, the AI could not use caravans or spies effectively, at least no where near what a human could, would send slow streams of units that I could take apart piece by piece, never seriously threatening me and I could go on and on.

Sure, the AI in civ3 does some odd things, but really, I can't begin to compare the abiliity of the AI to that of Civ2. The challenge is much greater for me now. No more invincible howitzer rushes at the end, thank god.

The AI is programmed to build as many cities as it can and attack in numbers. Really those are the only improvements made to the AI.

Oh wait I forgot, the AI can manipulate spies better; and caravans; and it can get around a ZOC blockade better; and it can use air bases more effectively; and it can manage home cities better; and it can terraform better; and ...

[asleepathewheel]

Originally posted by Sze


The AI is programmed to build as many cities as it can and attack in numbers. Really those are the only improvements made to the AI.

I think thats a pretty significant improvement in the game, you do not? For me it changes the AI from a patsy (in Civ2) into something that is more competitive

Originally posted by Sze

Oh wait I forgot, the AI can manipulate spies better; and caravans; and it can get around a ZOC blockade better; and it can use air bases more effectively; and it can manage home cities better; and it can terraform better; and ...

Thankfully, neither the AI nor myself have to bother with those anymore. Though airbases would be alright to have back, as would some limited terraforming.

Have you actually played Civ3 (it seems many of people who complain of the game actually have little or no experience with it)? The AI IS better than in Civ2. Whether this is because of the streamlined trade and spying or because the AI expands rapidly and is more able to attack, I don't care, it makes the game more challenging (for me) and thus more enjoyable. This doesn't mean that the AI will not do dumb things, but the AI in civ 2 did some inane things as well. What about the polar fortresses? Very effective to prevent circling the world by land. And I'm sure that for every critisism of civ3's ai you have, i could find one for civ2, if prompted, but I don't think its necessary.

[Coracle]

The AI being programmed to build cities - as many cities as possible EVERYWHERE - is NOT an improvement. It is asinine and a big joke.

The AI will spend its limited resources building settlers that it dispatches to every open tile it knows of - and it knows of most of them as the AI cheats and clearly can see the whole map.

It settles in deserts, tundra, and deep into a rival civ's territory where the town will eventually likely Culture Flip (another crock). The AI will send a settler wandering across enemy territory right past enemy cavalry to try to settle the open tile where the just razed city was! I saw the AI do that three times in a row, and each time I destroyed the settler and its pathetic foot soldier escort.

The AI shows how STUPID it is when it tries for turn after turn to get to those four open tiles in the middle of my kingdom (which they should not even know of) and I just keep moving warriors to block him. Another waste of resources and time by the AI.

The diarrhea of settlers flooding the map is intensely irritating. None too smart, either.

[asleepathewheel]

Originally posted by Coracle
The AI being programmed to build cities - as many cities as possible EVERYWHERE - is NOT an improvement. It is asinine and a big joke.

So I take it you would call the ICS of Civ2 asinine and a big joke as well, eh? I certainly would myself, I tried it once and never bothered again. But I also think that it makes the AI in Civ3 more difficult to handle, as you have to expand rapidly to secure land for later resources. I fail to see how this attribute of the AI is a joke.

[/QUOTE]
The AI will spend its limited resources building settlers that it dispatches to every open tile it knows of - and it knows of most of them as the AI cheats and clearly can see the whole map.
[/QUOTE]

I have seen games where the AI never fills in the entire map. Of course, I play on huge maps either continents or pangea, where there is more than enough land to go around.

[/QUOTE]
It settles in deserts, tundra, and deep into a rival civ's territory where the town will eventually likely Culture Flip (another crock). The AI will send a settler wandering across enemy territory right past enemy cavalry to try to settle the open tile where the just razed city was! I saw the AI do that three times in a row, and each time I destroyed the settler and its pathetic foot soldier escort.

The AI shows how STUPID it is when it tries for turn after turn to get to those four open tiles in the middle of my kingdom (which they should not even know of) and I just keep moving warriors to block him. Another waste of resources and time by the AI.
[/QUOTE]


The diarrhea of settlers flooding the map is intensely irritating. None too smart, either. [/QUOTE]

It has been said by others on this site, that if the AI is irritating, you. it is probably doing something right.

While there are definately problems with the AI, and I agree with you in part, I think that it is an improvement over Civ2.

[ALPHA WOLF 64]

You've seen spots unfilled by AI cities? What level? After I raze a city, its a guarentee theat every AI civ with a settler anywhere near will immediately be rushing towards the open spot. thats ok by me, my units use them as cannon fodder

[asleepathewheel]

Originally posted by ALPHA WOLF 64
You've seen spots unfilled by AI cities? What level? After I raze a city, its a guarentee theat every AI civ with a settler anywhere near will immediately be rushing towards the open spot. thats ok by me, my units use them as cannon fodder

I usually play on monarch or on emperor, but like I said, I usually play huge pangea, which often do get filled, eventually. But I have seen times where this doesn't happen. It also depends on how many civs I'm up against. of course, the more civs you have, the more likely there is to be no open land, but playing against a modest number, there may be.

[PatLasch]

Originally posted by Coracle

It settles in deserts, tundra, and deep into a rival civ's territory where the town will eventually likely Culture Flip (another crock). The AI will send a settler wandering across enemy territory right past enemy cavalry to try to settle the open tile where the just razed city was! I saw the AI do that three times in a row, and each time I destroyed the settler and its pathetic foot soldier escort.

Maybe the AI is planning for a culture flip to put you over the optimal city limit. And into corruption.

[The Thinker]

Originally posted by asleepathewheel

It has been said by others on this site, that if the AI is irritating, you. it is probably doing something right..

Declaring war on someone who has been an ally for a thousand years and is 10 times your size, more veterans that you have units, and money to burn, thus ending a trade of luxury for luxury plus gold is not right, but it is irritating.

Rik

[asleepathewheel]

Originally posted by The Thinker


Declaring war on someone who has been an ally for a thousand years and is 10 times your size, more veterans that you have units, and money to burn, thus ending a trade of luxury for luxury plus gold is not right, but it is irritating.

Rik

That does sound quite irritating, though if I was as large as you, I would be glad for the opportunity to take the luxury off their hands.

but, you're right, that doesn't make sense. if that is "not right", well, I don't know if I would go that far. were you at war with other countries? perhaps they were bought out by another power?