Rts AI?

[Spectral Paladin]

Alright I was in this discussion about whether it's better to play against a human or cpu opponent. I was pretty convinced that AI, when it comes to rts games, would never be able to compete with humans. But I had several ppl disagreeing, saying that pretty soon it will.

Now I realised that for the last few years I 've been lost in the mmo world and I have no clue in the matter. Is it true what they were saying then? Will there be cpu opponents that are able to battle it out with a human player with no resource/build time advantages? I find it quite hard to believe, given that the human player can acquire experience and come up with tactics the developers simply don't have the time to...

[Acriku]

I've heard of AI that evolves, in a way remembering what happened before and adjusting. As far as building and money handling, it'd have to be superior. As soon as what's built is done, it immediately goes to the next while simultaneously covering the entire field with procedures and whatnot. I think it's in the near future if not already here.

[Cyborg]

Well, right now it's a long way to go. To make an AI seem tough today, it usually begins with more resources than you or something like that.

[Andrew]

What about an AI that copies your every move? Would it end the game in a stalemate?

[Sneakgab]

''I've heard of AI that evolves''

Reminds of the much hyped ''radiant'' (or whatever they called it) AI of half-life 2 that supposedly was to do just that. Instead, the enemy AI was less advanced than most bots and pretty much just ran at you and followed explosive barrel related scripts... oh well.

Right now they seem to have trouble making AI that won't follow a single enemy to his doom, squad mates that don't throw themselves of mountain andor into their own grenades,e.t.c. So from my experience it seems like decent non-script reliant AI is aways off.

Either improving AI is ludicrously difficult, or most desighners just don't bother. Simple unit AI in strat games today is pretty much the same as in RA 2, EE,e.t.c from many years ago, with perhaps some added options like: ''hold position'', or , ''standard'', that come with their own stupidities which garauntee that you can't leave anything on it's own for longer than two minutes without it killing itself (though these things are generally still very useful though for some reason they seem to have been largely absent lately).

Reminds of some comedic AI moments Iv'e seen before. Anyone know Total war 2 (medieval). I had a cannon crew, which comes with twenty men (3 for using the cannon, 17 as, you'll soon see, neccesary replacements). One of the fools was standing directly in front of the cannon when it fired, resulting in his doom. Of course, him and his position was promptly replaced with 1 of the 17 fools, who befell the same fate. The pattern continued till the crew was thinned down to 7, at which point I tired of what was initially amusing and ordered the crew to move. However, they assumed the same positions until two remained, who were no longer able to operate the cannon but still obeyed the attack command which sent them running towards the towers (invulnerable to inf of course) and their deaths. Thusly, with a simple command of ''attack the walls'' a 20 man cannon crew went inextricably to their deaths.

Such scenes tend to lessen my faith in future AI improvements

[X3M]

Well, 5 years have passed. Time to bumb this interesting topic, since I wasn't on this forum yet back in those days.

What do you think about AI these days? :)

The best AI in RTS are created by Blizzard in my opinion. They don't "really" cheat. Except the Insane settings.

However, they do seem to know what kind of strategy you are using on very hard, without scouting :D.

So cheat free would be the hard setting. The AI also focusses fire on certain units during a fight. Killing of your units 1 by 1 instead of damaging them all.

Although, some micro management is still missing. Like aiming projectiles on units where it's effective against. They didn't do this, they simply created units which didn't have any other option. Like AA units in a ground versus ground battle, where the colossus get hit by the AA units.

[MrFlibble]

I haven't played much newer RTS games, so I have no idea what modern AIs are. On a slightly related note though, the AI in C-evo (a turn-based strategy game) seems to successfully pull off the trick of being hard without cheating.

[X3M]

With starcraft/broodwar I created fair and hard AI triggers myself.

First a scout unit explores, watches your army, then retreats. You might kill it, but that doesn't matter. You better prepare for what is coming.

Once your army has been seen at that location. The enemy starts building what is appropriate for countering. And enough of it for overpowering at that location.

In that map that I created back then. There are infantry, armoured and flying units. And their weapons as well allow them to have 9 different kinds of units.

One of the armoured types is chosen by random, or all 3. Then the units are build that are good against the army that you had at the triggered location. If you had a lot of infantry, then the AI builds a lot of anti infantry.

Since it's random, you don't know what is coming unless you scout for yourself. Anyway, if you weren't active enough, your armies would be falling 1 by 1. While the map was properly balanced for the computer and the player.

It took me a lot of triggers to pull this one off. Perhaps this is what is lacking with programmers. I never succeeded in aiming for the right units with certain other units.

Except for 1 time, where your units from a certain type are actually immortal for a while until another type is dead. But this could be abused. So I discarded that trigger.

I just noticed while playing WC3, that certain units tend to try to reach a heavily damaged unit. And sometimes all units focus on 1 unit. But this might be involuntary.

[Spectral Paladin]

I haven't played any RTS in a long time. But I play chess and I 've also had a look at chess engine programming. Needless to say, against the best engines on a good machine, only a top grandmaster can hope to get a draw with very careful play.

There are 'neural network' algorithms - basically AI that learns, as Acriku said back then.

But of course, chess is a game of perfect information where brute force computation goes a long way. And even so, - apart from increasingly powerful computers obviously - it took decades to develop the algorithms we have today and the evaluation functions themselves draw from humans' 100+ years of experience to assess a position. RTS games stay popular for a few years; there's no time to reach that depth of knowledge.

[MrFlibble]

I just noticed while playing WC3, that certain units tend to try to reach a heavily damaged unit. And sometimes all units focus on 1 unit. But this might be involuntary.

This is actually a pretty old trick in RTS games, I'm sure I've observed that in Command & Conquer already. I think when the individual unit AI handles target selection, it takes into account several factors such as the state of the potential target (damaged or not), its proximity to the attacker, general threat value etc. I guess this is one of the easiest things to pull of with the AI in strategy games.

On another note, recently I've read an interesting article about en experiment that involved custom AI scripts for Age of Mythology that attempted to emulate emotional states associated by the Big Five personality traits. These AIs were pittted against the standard AoM AI bot, and while all of them won most of the matches, the neurotic AI turned out to be the best winner. Here's a recap of the article:

http://www.newscientist.com/blog/technology/2007/10/neurotic-software-is-top-gamer.html

[X3M]

The AI in that game is rather bad. I asked 1 of my co-workers who plays this game a lot. He doesn't like the AI, it's being predictable. No wonder that bots, which are made at a later stadium, are better then the AI of that game.

Of course, chaos (read worst) players still have a good chance against bad players in most RTS. Since the bad try to guess what's coming, where the chaos just doesn't think at all and rushes in with 'rather strange or mixed up forces. Not what the bad player expected.

In a Dune2000 example (and correct me if I am wrong with the strategies, I only played practise, never online):

Bad player, lots of combat tanks.

Chaos player, something of everything and on the attack since he doesn't know when to attack.

Where the mixture of combat tanks with missile tanks are rather good but outmatched in numbers. But then again, there is a lot of infantry and vehicle fodder around. Even the siege tanks are out there as fodder. All in a close pack, since he knows that would be good.

The Bad player tends to crush most of the infantry by moving. He succeeds, but he is already losing units. Then he focusses on missile tanks? A lot of his units also try to reach the selected targets. Meanwhile, the units of the chaos player just fire away since the chaos isn't even trying to battle. It will be getting real close. While the bad player focusses on destroying units, the chaos player simply thinks, "I loose that one". And continuous building mixed reinforcements. The bad player also will start to forget to actually crush those annoying troopers :).

Ow no, what doest the chaos player do now? Some groups are actually already into the bad players base. Not knowing what to do, they just kill singled out units. Like harvesters etc. Bad players goes back to base and doesn't focus on the main battle field any more.

Some are also in the field, killing harvesters.

The chaotic missiles tanks, have plenty of time for focussing on carry-alls.

So a summary, chaos goes fast and on the attack and does radical things with mixtures. Bad player tries to focus on micro, but fails because the accidental complexity of his opponent is too much.

Only counter by the bad player would be, rushing first, taking out income.

What do you think?

[vota dc]

A strange thing is that once I added a weird unit for Atreides in EBFD. It has contaminator model and shoot inkvine projectile with a different warhead: they damaged only light vehicles. The AI didn't build that until I spammed a lot of dust scout. That was awesome: the unit build the unit when it was useful and I even didn't touch the AI.
Then I played with Red Alert 3 and gave cryocopter and vindicator to Empire....AI never built them. It doesn't even if I edit AI. Even with C&C generals I had the same problem.