My attempt to replace the default BF2 strategies turned into the project this post describes. The original code and project designs were created with a pencil and a notebook in the deep woods of an Alabama hunting camp. You don't need a computer for everything.

In short, I have tried to improve the BF2 AI Commander, and due to all the positive feedback from the members of this forum, I believe I have succeeded. When I first created this I thought I would be the only person to ever use it; I was mistaken. A huge Thanks goes out to all the good people at BFSP who have donated their time and energy in testing my work and giving me the feedback I needed to make it better.

The name of this project is "Enhanced Strategic AI",or simply ESAI for short. If you are impatient, the download links are at the bottom of this post.

News: Beta Testers Needed. Read This Post




ESAI is FREE SOFTWARE. It has no copyright or usage license. The only restriction on use of this code is that you may not redistribute it for a fee unless you need to cover the marginal cost of distribution media. The key word is "cost" of the media. You may not use that as an excuse to turn a profit. Individuals who break this rule will be subject to the following vague and non-incriminatory statement of my position:



So what exactly is ESAI? It is an alternative approach to BF2 Strategic AI scripting that gives the AI commander more strategy options. ESAI is designed to enhance each team's cohesiveness and overall effectiveness.

The ESAI package is not exclusive to any particular mod. It has been tested with dozens of them. Here are the answers to the most frequently asked questions about ESAI. Please, restrain yourself - I will no longer respond to queries regarding the information below:








ESAI has now been tested extensively, and it is known to be stable. If you have any crashes related to ESAI, you have almost certainly made a mistake setting it up. Get help from someone who is already using ESAI.



ESAI includes 4 default strategy sets for use with different styles of maps. Strategy Sets are assigned to specific maps on a per game mode basis,using a specially crafted 'Strategies.ai' file. This file loads the ESAI core code,any required plugins,and the strategy set that is to be applied to the game mode. ESAI does not override the default strategies of any mod. If ESAI is not activated inside a map, then the default strategies are loaded as usual.

New (5/13/2011):

The ESAI core now contains over 30 working strategies. The default Strategy Sets assign 12 strategies to each team, and there are more complex strategy sets available in the user directory tree.

ESAI uses a plugin system to allow coders to craft new strategies without reinventing the wheel. A user written plugin can create a strategy by making use of the conditions and prerequisites already defined by ESAI. Plugin authors can also create their own conditions,prerequisites,or strategies as needed.


There was once a branch of this project written specifically for Forgotten Hope version 2.3. That variant of ESAI is now obsolete; FH2 has made many changes to the mod since then. That version had a several custom strategies specific to fh2 maps that have since changed. You can still use the standard ESAI version with FH2.

DOWNLOAD LINK

ESAI v4.2 Public - Now with new-and-improved documentation:

Download ESAI 4.2 Public Release

ESAI v4.1 was exactly the same as v4.2 except for the included documentation. If you are still using 4.1 there is no real reason to download version 4.2, unless you want to read more details about how the code works


I have noticed some spam websites that have posted ESAI crap download links. They are using the typical tricks of posting a zoo of different and confusing d/l options and buttons etc, seems they mostly lead to that site's "automated download assistant", which is of course an executable that is dubious in nature - read "possible spyware". I give this warning for people who may have discovered an older cached version of this post, and took the extra step of coming here to see what has changed.




I have retired from the BF2 world. If you have read this entire post then the requirements for redistributing ESAI should be clear.

BobTheDinosaur has been kind enough to agree to take charge of all ESAI permission requests. (Thanks again man). He has full power of attorney over this project, and speaks on my behalf. If you are still unsure if you can use ESAI with your own project, ask him for permission.

Any future changes BobTheDinosaur decides to make to the rules I have posted must be respected. A minor change has already occured - you now have to credit me if you use ESAI in your mod. I see no problem with that. If for some reason you submit a request and it is denied, his decision is non-negotiable, so don't bother to argue with him.

That said, Please do not pester him overmuch with personal requests for Technical Support. If you are having problems with ESAI setup I would encourage you to post your questions in this topic; there is a high probablity that the BFSP community will help you out.

On a personal note, I would prefer that authors of mods that are strictly AI enhancements not include ESAI as part of their project, but that isn't strictly a rule. As far as that goes, anyone is welcome to try and expand on ESAI or Improve it , but it would be nice if you renamed it slightly in order to make a distinction between my work and yours. Nothing elaborate, just add an extra letter to the name or whatever. This isn't an actual rule either, it is only my preference.

Hello Void and welcome to Battlefield Singleplayer.

Fascinating work. Looking forward to future developments.

Yeah, that was a real mouthful for my first post in this forum. I hope there are indeed future developments,but I need to first see if there is any community interest in what I've written so far.

I'm downloading and will test it in my own mod to see how it affects the bots!

I like the concept. Used it on AIX Iwo Jima and Aberdeen, and it seemed pretty intense, some flags that weren't usually getting capped did get capped, although it may be a freak incident. requires more testing!

ESAI has been updated to version 2.7b. The download link is in my first post. I won't go into a detailed change log here, but I will say that I think the new version achieves some desired effects.

The new version is backwards compatible with the initial release. You can install 2.7b without breaking any maps that are already hooked to ESAI. This will always be the rule when ESAI is updated. As always, comments and feedback are welcome.

Interesting work, Void.

Do you find these strategies help squad cohesiveness? Or just stream the bots more efficiently?

One of the major design goals of ESAI was to stream the bots more effectively. I think I may have accomplished this to some degree.

I've also tried my best to create strategies that result in sane Commander orders,though this is highly dependent on the quality of the map's design - particularly with regard to well planned SA neighboring.

In my tests I've noticed a higher level of overall action. I've also seen more CPs getting capped that usually don't get touched when I'm running the Vanilla default strategies.

ESAI seems to also increase "squad cohesiveness",as you put it.I think this is a side effect resulting from better management of the team as a whole.

It has never been my intent to produce perfect strategies.Just as important as my other design goals is the desire to create a framework that others can expand on, and that inexperienced SAI scripters can learn from.

Well I've seen that the bots seem to be much more aggressive which required that I turned down the difficulty to .9 as they seem to head-shot me much to quickly.

Has made it much more difficult to grab flags without an immediate counterattack happening.

ESAI is now at version 3.0. The biggest change is that the SA temp multipliers used in the core are now constants defined in a seperate file. There are some other minor improvements as well. This release works with all maps hooked to previous versions of ESAI. 

Download link is in my first post.

GONA ETEST!~

CAN SOMONE explain how i install this. do i drop most of the foldser into the mod directory. and just put the map files into the ai folder in each gamemode?

 
Sure. The easiest install is just to copy the ESAI directory into [bf2Directory]\mods\bf2, so you end up with \mods\bf2\ESAI.

After that you add your choice of map file to \[level]\server.zip-->\GameModes\[gameMode]\[numPlayers]\AI\.

You can add the ESAI map files to levels in any mod, regardless of where you put the ESAI folder. If you install ESAI to a directory other than \mods\bf2\, you will need to edit the paths inside the default map files before you use them.

If you still need help, feel free to PM me.

so i throw the file named STRATEGIES. from what ever strat i choose and just dump it in an ai folder? in a map game mode

Yep. Just pick a `Strategies.ai` file from \ESAI\MapFiles\default\[strategy]\ and put it in the AI folder for the gamemode you want to test. (Same place in server.zip where the file `StrategicAreas.ai` lives.)

Hey, good job on the Strategic AI System
I will use it for AIX 2.0 and see if there are many big changes.

my ai seems. a lot. lot more aggressive. and they react a hell of a lot faster

Are you saying that the ESAI strategies make this happen, or that the AI you were previously using is more aggressive ? (Hopefully you are talking about ESAI.)

Could you explain what the difference is between the map sizes?

The different map sizes are just different organized sets of ESAI strategies. As you go up in size, the number of maximum attacks per strategy family increases, as does the time limit for the strategies.

If you look at an ESAI strategy set (the ai file that actually assigns the strategies to each team) you will see a number after each core strategy, such as "basicAttack2". The 2 here means a basicAttack strategy with a maximum of 2 attacks.

Subsequently, a "map size" should be chosen based more on the number of control points in the level, as opposed to geographic space.

ESAI has undergone a major update to version 3.5. The download link has been updated in my first post.

As always the new version works with all maps hooked to any prior ESAI release.

Features include better documentation,new strategies,extra map files,more plugins, and a library of stock conditions ready for use in your own plugins. All new content is separate from the ESAI core and default files - it has been added to the user directories.

Feedback and questions are welcome as ever.

Sounds great. I've added this to all my favorite maps, it really does make a difference. If anyone can't decide about downloading this, the answer is YES, you should.

I have made a minor update to the ESAI package:

All claims of copyright have been removed; now anyone has my permission to use and distribute ESAI however they please - provided no one charges anyone money for it.

Folks haven't exactly been beating down the door to get to this thing, but there have been several downloads, and the feedback I've gotten has been mostly positive.

If the admins here think it is worthy of it, this thread can be moved to community mini mods. ESAI is now a community release.

Any feedback is encouraged, and requests for help will be answered. There is contact info in the ESAI readme, though I do still check this board from time to time.

Enjoy.

I appreciate the work.

Yeah, well - it was fun creating this system, especially learning how to make plugins load correctly. It also taught me much about writing SAI code for BF2. I see, at the time of this writing, that 15 people have d/l ESAI since I posted the "copyright free" updated package. I hope you and everyone else gets some good use and enjoyment out of it.

I used the old version on AIX Aberdeen and it made the AI hard to beat. Thanks for all of your work on the AI.

Okay, I'm going to give it a try -- it sounds interesting! Thanks, Void!

Seems that people are actually interested in this project after all. I may as well add that I am willing and able to write custom strategies for deserving SP/COOP maps.

Interested map authors, feel free to PM me, or send a request to the email address given in the ESAI documentation.

Good to see BF2 living on with fresh ideas and mods still being developed (I even bought the BF2 complete collection (only $20) the other day to make future installing easier - I have never bought two copies of game ever!!).

I have had not a chance to try this package yet, so just wondering if these AI improvements have eliminated or reduced the spinning bot issue? Has anyone seen spinning bots using this AI?

Thanks for sharing your work!!

ESAI doesn't eliminate spinning bots, but it doesn't make the problem any worse either.

Spinning bots can be minimized by reducing the number / opportunities for bots to attempt to use handweapons on aircraft. While it may look cool for a heavy machine gunner to shoot at a helicopter, he is not doing much damage realistically and will get owned shortly.

I have a question
why my BF2 will crash after i used your mod?? (only the map i intalled ESAI )

Ok, ESAI can crash BF2 under three conditions:


1. The mod you are using it with has default strategies with the same names as the ESAI strategies (unlikely)

2. The file path is incorrect in the map file you added.

3. The ESAI folder is not in the expected location.

If you don't want to edit the paths in the map files, make sure you have extracted the ESAI package to \mods\bf2

The directory structure should look like this: \[battlefield install directory]\mods\bf2\ESAI

I will be happy to help you further if you can give more details about how you installed ESAI and the nature of the crash. Just post here or PM me.

THX that helps
btw My BF2 get crash usually after i use ESAI why?
its like after few minutes I join the game it'll get crash

 

I've never had this problem - if there is an issue with the ESAI setup, the map will either crash while loading, or else crash the moment you first spawn in.

Lots of people have tried this system, and you are the first to report any crash issues...I'm not sure what is going on with your game.

All I can think is that you might be adding the file "strategies.ai" to the map's main \AI folder - it doesn't go there. The ESAI map files go here:

server.zip-->\GameModes\[gameMode]\[numPlayers]\AI.

EDIT: I thought it might be a problem with patch 1.5, since ESAI was developed and tested under patch 1.41. I just made it through an entire 600 ticket match in my personal SF mod under 1.5, and was running Warlord 64 player version with ESAI enabled.


What mod are you getting the crashes with?

nope there's on problem with the ESAI setup. I fix the first problem that I said it . but i haven't fixed the second one .
The mod i used is my own mod . I'll try others mod to make sure that there is nothing wrong with ESAI. and yeah I used 1.5 . maybe it's my mod issue. I'll check .

Does it eliminate trapped bots? I often have a bot that will get stuck behind an object (e.g., UAV trailer on AIX carrier) and can't find its way out. If I issue a "get in" instruction, for example, the bot will respond positively with "you got it" or similar, but continues moving around behind the object instead of going around it and toward/in my vehicle.

Does it do anything about bot drivers? Not only are bots generally poor drivers, slow and indecisive, but the other day, I watched a bot repeatedly ramming his FAV into an empty/parked FAV, obviously doing nothing to further the cause of his team.

Or, does your project merely enhance overall victory strategies, whereas these issues are more of a pathfinding/navmesh problem (assuming that's what they are)?

Lastly, I've never seen a bot use TV missile in vanilla or AIX. Does ESAI give bots the ability to use the TV missile, or is it hard coded into BF2 that the bots cannot be made to use it?

Welcome to the BFSP forums SP4Me.


What map was it? "Operation Road Rage?"

HAR HAR!


I believe that's the focus of this project. Bots making better choices in strategies to enhance difficulty against players and offer acute playing ability of winning in a given map, and not so much overall intelligence (such as driving and pathfinding).

Granted that's my understanding of this project, Void of course will be able to elaborate much further and to the point.

ESAI is Strategic AI code. It cannot alleviate the basic limitations of BF2 bots, some of which were enumerated by SP4Me. It works at the AI Commander level, controlling which Flags are attacked, when they are attacked, and with what level of resources.

The Vanilla BF2 Commander only has one basic strategy to work with 99% of the time - just a basic attack strategy. ESAI gives the AI commander more options. At the ESAI core there are sets of strategies for when a team is behind on flags, when the number of flags are even, and for when a team is ahead on flags.

Further, the core ESAI strategies are divided into *attack and *attackHarder families, and these strategies have time limits. The result is that there are intervals where bots are more likely to spawn near vehicle depots/airfields, and intervals where they are more likely to spawn at the front lines.

There are many more strategies available than just the core strategies. They are implemented as plugins. The default strategy sets use some of these plugins; more are used by the user space strategy sets.

At its most complex, ESAI provides 12 different strategies per team. At its simplest,it provides 6 strategies per team.

To summarize, ESAI attempts to streamline the bot orders as well as enhance the flow of well equipped soldiers to the front line battles.

It appears as if the individual who writes custom strategies for a given map is playing Chess with the players/AI of whomever takes his AI to task. Void you make writing AI sound like fun.

Congrats btw on creating one of the more popular threads (aside from stickies) in "Advanced Topics" these days. 39 replies in 3 pages with 2,410 views as of this post. Who says Singleplayer/Co-Op BF2 is dead?

With this do the ai still follow the strategic neighbours set by the mapper or does this make them ignore that.

Strategic Area (SA) Neighboring is still obeyed. There is no way around this, and I wouldn't want there to be. In fact, well planned SA neighboring and map layout go a long way toward letting ESAI really show an advantage over the Vanilla code.

In fact, ESAI seems to make BF2 even more sensitive to bad SA neighboring. For example, two-way neighbors to uncappable flags drive the Commander absolutely insane when ESAI is running.

Further, ESAI can be made more effective by adding extra SA objectTypeFlags. Most SAs have at least the flag for ControlPoint set. ESAI supports other flags as well. For example, to reduce bot's spawning at far away locations, an SA can be flagged as Remote. The full list of supported SA objectTypeFlags, and how to add them to Strategic Areas, is included in the package documentation.

Ok, will look elsewhere for basic bot behavior fixes, if any exist.

ESAI sounds fun, so I'll try it when I get around to creating a dedicated 1.41 install (still mad at EA for breaking the Commander in 1.5!).

Btw, does ESAI work well with AIX?

don't get your hopes up too high. BF2 uses reactive ai for its bots. this means they can be dropped into any scenario at any point and they will be able to operate correctly, but this also means they might appear somewhat unrefined when compared to e.g. another game's bots with scripted ai, but scripted bots can only work within the area for which their script was written. some bot issues can be fixed. some have kludges or workarounds. the rest we have learned to live with.

trapped bots are a navmeshing issue and can only be properly fixed by repairs to the navmesh.

BF2 bots will always make crappy drivers, but a good SP mapper can bear their driving faults in mind and can make an SP map with fewer potential 'bot disaster points' than the average MP mapper would.

hehe.. nah, it was AIX Refinery 64 at the lab:




I tried to fraps it, recreating the vehicle positions several times tonight, but the bots managed to either push the FAV out of the way or back up and continue on their merry way behind the two parked ones, so it was apparently a fluke. Or, either I didn't get the angle/distance precisely the same as before, or some bots are just dumber than others.

ESAI was developed and tested under the HardJustice mod, but it works well with every mod I've tried it with. People here have tested it with AIX and reported positive results.

One thing I've noticed about many AIX maps is that the Strategic Areas often have very high basic temperatures. ESAI doesn't require high SA base temps, and you can set these back down to around 50, if you are using ESAI with an AIX map. ESAI will still run fine in AIX if you do not bother to do this however.

I've posted this over at the FH2 SP site to see if they'd be interested in using it to enhance their gameplay.

Thanks Bubbles. Glad you think that the project is worth spreading around. If mappers / modders would get more interested in it, the code has a lot more potential than folks just using the strategy sets I made. ESAI is designed to be tinkered with and expanded on.

I don't play much FH2, but I have at least tested ESAI with that mod and gotten good results.

would it be possible to use your superior AI to stop planes from flying off the map all the time in ITHH's battleaxe?

Uhm, not unless the AI commander is ordering them to fly away, which he isn't. I have noticed however, and others have reported, positive side effects from ESAI that don't seem to be directly related to the AI commander, so I suppose you could try it out and see.

Maybe you should just replace the planes with attack helicopters?