The AI Sandbox

Capture The Flag Phase #3: The Results

Alex J. Champandard — Sat, 16 Feb 2013 23:02:30 +0000

The CTF AI Competition had ambitious goals to drive forward the field of Game AI by challenging developers to write AI commanders for a tactical objective-based game. It wasn't until this final round that this potential was fulfilled, revealing some amazing ideas and technology from many participants. We'll be posting about that soon!

The Phase #3 Tournament involved running over 8,000 matches between commanders submitted by students and enthusiasts from around the world. These were written in a number of different programming languages — including Python, C++, Java and C#. The tournament included some modified maps from the official SDK release, and new unseen maps as well.

NOTE: Special thanks to Guerrilla Games for supporting the competition and don't forget they're recruiting AI programmers! Also, if you'd like to help with future AI competitions, AiGameDev.com is hiring too :-)

Tournament Results

The winner is ... Alexander Shafranov. His KEFIR commander combines threat prediction and global map awareness using an influence map, as well as a hierarchical task network plnner. Congratulations also to team Terminator and Chris St. John who provided fierce competition and solid decision-making throughout the online ladder.

Rank	Commander	Wins	Draws	Losses
1	Alexander Shafranov #35	72.4%	9.6%	18.0%
2	Terminator #17	69.7%	11.9%	18.4%
3	Chris St. John #53	60.0%	16.2%	23.8%
3	Traffic Jam #44	60.0%	15.8%	24.2%

3rd place is declared as a tie between CSJ and Traffic Jam, who switched places regularly during the final competition and are practically inseparable in the final rankings. The full results of the competition can be found on the Tournament Results page.

Match Recordings

Here are just a couple of the tournament match recordings. More recordings are available from the commander pages linked to in the results.

Kefir vs. Terminator

Chris St. John vs. T-Dup

Traffic Jam vs. Locutus

In Retrospect...

With thousands of submissions from hundreds of participants, hundreds of thousands of matches over three phases, the CTF Competition is now over! Thanks to everyone for participating and for your kind words:

We'll be announcing the future of Capture The Flag as a game/simulation, its codebase and the competition, in the near future. If you'd like to be involved in the early stages don't hesitate to register on this site and we'll keep you notified by email.

Thanks everyone for participating!

CTF Update 1.7 and 1.7.1 Release Notes

Alex J. Champandard — Tue, 15 Jan 2013 15:27:39 +0000

This release adds bug fixes and minor gameplay changes for the Phase 3 of the Capture the Flag competition. Gameplay changes include tweaks to the reaction rate of bots to events and the filtering out of consecutive waypoints that are close to previous waypoints(less that 1.5 metres).

There will be no major gameplay changes for the Phase 3 competition. Releases will only be made for bug fixes.

The AI Sandbox 0.20.7

The AI Sandbox is is available for Linux (32 bit and 64 bit) as well as Windows.

Capture The Flag SDK 1.7.1

This SDK release is available for Linux and Windows.

Bug Fixes

Stopped dead bots from being able to pick up flags. This also fixed a problem with being spammed with flag picked up and flag dropped events.
Fixed several issues causing a degradation in performance during a game.

Capture The Flag SDK 1.7

Gameplay Changes

Reduced the bot perception delay to game events (including player kill events and flag events) that are not visible from 1.0 seconds to 0.7 seconds.
Consecutive waypoints that are too close (less than 1.5 meters) from previous waypoints are now filtered out of Attack, Move and Charge commands. This has been done to discourage micromanagement of bot behavior.
The information about a newly spawned/respawned bot is fully known in the frame that they are spawned.
New orders from the holding state, e.g. Attack Move or Charge (not defend) have 0.0 delay.

API Changes

Changed the semantics of BotInfo properties to remove cases where values were None. The properties position, facingDirection, health and state now contain either the current information for friendly bots or visible enemy bots, or the last known values otherwise.
Added BotInfo.STATE_DEAD. The health and state of dead bots are always known. It is now possible to test for dead bots by either comparing health == 0 or state == STATE_DEAD.
Rewrote the python network client to allow commanders to read from the network socket in a separate thread. This prevents the network from timing out if the commander takes a long time to process its initialize or tick.

Bug Fixes

Fixed LevelInfo.respawnTime not being set.
Fixed duplicate bot respawns events sent to network clients for initial spawns.
Fixed bot not stopping outside of enemy firing arc during attack order
Fixed cases where a bot does not respond to a nearby kill event.
Handle client disconnect error while waiting for clients to report 'ready'. This is now correctly flagged as a commander failure.
Fixed the visibility rays so they are displayed with correct alpha.
Fix for finding a random free position in box.
Fixed some maps that were not symmetric.

C++ Language Pack 1.4

This language package is available for both Windows and Linux.

Updated the network protocol version to 1.4. This contains the required changes to support the new BotInfo state STATE_DEAD.

Java Language Pack 1.4

This language package is available for both Windows and Linux.

Updated the network protocol version to 1.4. This contains the required changes to support the new BotInfo state STATE_DEAD.
Vector2 x and y members are now private. Vector2 should be treated as an immutable objects and new Vector2s should be created rather than modifying existing ones. Note, setters do exist for modifying x and y if you insist.

Other Language Packs

Other community supplied language packs are listed on the Download page.

Capture the Flag Phase #2: The Results

Alex J. Champandard — Thu, 10 Jan 2013 16:43:03 +0000

The CTF AI Competition was created as a programming challenge that reflects the development of AI for AAA video games. Competitors were required to write commanders to control between 4 and 15 bots in a team-based game of Capture The Flag, with gameplay mechanics inspired by a combination of FROZEN SYNAPSE and KILLZONE 3.

The Phase #2 Tournament was run between commanders submitted by 57 students and enthusiasts from around the world submitted AI Commanders in a number of different programming languages — including Python, C++, Java and C#. The tournament included some modified maps from the official SDK release, and new unseen maps as well.

Tournament Results

The winner is ... Terminator. His commander showed a strong mix of fast map traversal and cautious movement when close to enemies with just a small number of bots left for defending his flag. Congratulations also to Chris St.John who led the live leaderboard for most of the month leading up to the Phase #2 Tournament.

Rank	Commander	Wins	Draws	Losses	Games
1	Terminator #6	70.5%	9.2%	20.2%	173
2	Chris St. John #21	66.5%	12.9%	20.6%	155
3	S. Tilkin #7	62.8%	13.1%	24.0%	183

The full results of the competition can be found on the Tournament Results page.

Match Recordings

Here are just a couple of the tournament match recordings. More recordings are available from the commander pages linked to in the results.

Terminator versus S.Tilkin

Chris St. John vs. Terminator

Chris St. John vs. Neil Bui

Phase #3

Commander submissions are now being accepted again for Phase #3. This phase of the competition will end on Monday, February 11th 2013 at 11:59 AM UTC. Everyone is eligible to enter the competition, whether or not they competed in Phase #1 and #2.

This time there won't be any significant gameplay changes for Phase #3. There will be a minor release early next week to fix some minor bugs and to simplify some of the API. If you have already entered a commander in one of the previous phases it should continue to work for Phase #3!

If you're new to the competition, check out our masterclass on Scouting, Ambushing, Hunting and Sneaking Behaviors, visit the AiGameDev forums and chat to us in IRC.

Go to the Participate page for more info on how to enter.

CTF Phase 2 Closed. Phase 3 Starting Soon!

Alex J. Champandard — Tue, 08 Jan 2013 09:52:18 +0000

Congratulations to everyone who put an entry into phase 2 of the Capture the Flag Competition! The official tournament matches are being run as we speak and the results will be announced on Thursday.

After overwhelming feedback we have added a third phase to the competition. Anyone can join phase 3, there is no requirement to have competed in either of the previous phases. The live competition server will be offline until the announcements of the phase 2 results, however you can submit your commanders at any time so that it will be automatically run when the server is restarted.

If you're new to the competition, check out our masterclass on Scouting, Ambushing, Hunting and Sneaking Behaviors, visit the AiGameDev forums and chat to us in IRC.

Phase 2 will be run under the same rules as phase 3. We will not be making any significant gameplay changes, only minor bug fixes and tweaks. The closing date for phase 3 is Monday, February 11th 2013 at 11:59 AM UTC.

CTF Update 1.6 Release Notes

Alex J. Champandard — Fri, 21 Dec 2012 12:35:31 +0000

This release introduces gameplay features and balancing changes for the Phase 2 of the Capture the Flag competition. Gameplay changes include tweaks to bot action times and field of view, changes to the low-level Attack behavior and responding to bots triggering events nearby. These are described in more detail below.

There will be no major gameplay changes for the Phase 2 competition. Releases will only be made for bug fixes. A small bug fix release is expected to be made later on December 21.

The AI Sandbox 0.20.6

The AI Sandbox is is available for Linux (32 bit and 64 bit) as well as Windows.

Capture The Flag SDK 1.6.2

This SDK release is available for Linux and Windows.

Gameplay

Field of view is now 30 degrees if a bot is in the defend, 90 degrees while idle and while moving. This smaller field of view is compensated by a faster shooting reaction time when a bot is defending than if it is moving.
Bots will not target enemy bots if they are in an idle state.
Bots in an attacking state will not enter the firing arc of a visible enemy bot. If an attacking bot stops because of an enemy firing arc ahead of it its state will be STATE_HOLDING. If the enemy bot turns away or is killed the holding bot will resume its attacking order.
Reduced the shooting time penalty of Charge to be closer to the action time penalty. Charge should be used instead of attack if you do not want the attack pause behavior at enemy firing arcs.
Bots can no longer see dead people. Dead bots will no longer appear in the list of visibleEnemies of a bot.
BotInfo.seenlast for dead bots (including enemies) has been changed to 0.0, making it now possible to iterate through the BotInfo objects of the enemy bots to quickly identify how many of them are dead.
Bots that trigger events (killing another bot, picking up or dropping the flag) will appear in the visibleEnemies list of enemy bots that have an unbroken line of sight (even if they are outside the enemy bot's field of view). These bots will automatically be targeted by the enemy bot if they are within the target range. There is a delay of approximately 1 second between the event and the event instigating bot appearing in the visibleEnemies list or being targeted and the bot will remain in that list for approximately 2.5 seconds.
Fixed the defend order when issued without an explicit direction specified so that it resumes facing the initial defend direction after shooting someone.
Set BotInfo.seenLast to 0 for a team's own bots. This simplifies some algorithms that are updated by bot positions each frame because it is no longer necessary to test that (bot in team.members) or (bot.seenLast == 0) for up-to-date bot information.
Bots will no longer try to stack on exactly the same location.
Added a crouch animation for the Defend state.
Increased order and reload delays. Reload delay while defending is now the same as for other states.
Added new maps and map balance changes.

Implementation

Fixed a possible infinite loop in GridMapRegion::findClosestPassableNode
Fixed a bug which could cause a crash during initialization of the LevelInfo object.
Fixed characters lying down when respawned
Fixed a bug causing a team's flag to appear in GameInfo.enemyFlags
Updated the network protocol version to 1.3. This contains the required changes to support LevelInfo.fieldOfViewAngles and the new BotInfo state STATE_HOLDING.
competition.py script now displaying results indexed by opponent, for better insights into your bot's performance.
Added an acceleration mode that runs without pausing. Use argument --accelerate to simulate.py (or -a) to enable. Disable vsync in the demos.cfg configuration file (located in the config directory in the AI Sandbox install directory) for additional speed-up.

Python Commander API

New GameInfo helper function holdingBots for listing attacking bots that are blocked by enemy firing arcs.
Replaced LevelInfo.FOVAngle with fieldOfViewAngles. This is a list of angles, one for each state in BotInfo that a bot can be in. This allows per state values of the field of view angle to be used.
Fixed a bug with the MatchInfo.scores not being updated on the python network client.

C++ Language Pack 1.3

This language package is available for both Windows and Linux.

Updated the network protocol version to 1.3. This contains the required changes to support LevelInfo.fieldOfViewAngles and the new BotInfo state STATE_HOLDING.
Fixes for incorrect scores in MatchInfo.

Java Language Pack 1.3

This language package is available for both Windows and Linux.

Updated the network protocol version to 1.3. This contains the required changes to support LevelInfo.fieldOfViewAngles and the new BotInfo state STATE_HOLDING.
Fixes for incorrect scores in MatchInfo.

Other Language Packs

Other community supplied language packs are listed on the Download page.

Capture the Flag Phase #1: The Results

Alex J. Champandard — Fri, 14 Dec 2012 16:50:15 +0000

36 students and enthusiasts from around the world submitted AI Commanders in a number of different programming languages — ranging from Python to C++ — to compete in the Phase #1 Tournament. The tournament included some modified maps from the official SDK release, and new unseen maps as well.

Tournament Results

The winner is ... CurlyMo, thanks to a combination of solid defensive positioning and clever attacking. CurlyMo was in the lead in the online ladder, though the top five (last minute) submissions were ranked very closely, with different commanders doing better on different styles of maps. Special credit goes to Nick Caplinger's commander in second place, who was often ahead and impressed us with its decisions.

Rank	Commander	Wins	Draws	Losses	Games
1	CurlyMo #3	67.6%	11.1%	21.3%	469
2	Nick Caplinger #7	67.3%	6.3%	26.4%	474
3	RedTougu #8	62.8%	10.9%	26.3%	358

The full results of the competition can be found on the Tournament Results page.

Match Recordings

Here are just a couple of the tournament match recordings. More recordings are available from the commander pages linked to in the results.

Roger Valldeperas versus CurlyMo

Red Tougu versus Chris St John

Moduspwned versus CurlyMo

Benjamin Han versus Chris St John

Phase #2

Commander submissions are now being accepted again, and the automated ranking ladder is now fully operational. Anyone is eligible for competing in the competition; you don't have to have participated in Phase #1 compete in Phase #2.

We will be announcing some small tweaks to gameplay mechanics next week. There are unlikely to be major changes to the API so the existing commanders should continue to work for Phase #2. Now's a great time to enter as the rules will be changing, and you can use the best ideas from the current commanders by watching the replays!

Go to the Participate page for more info on how to enter.

CTF Phase 1 Closed. Phase 2 Upcoming!

Alex J. Champandard — Mon, 10 Dec 2012 13:08:31 +0000

We closed the submissions for phase 1 of the capture the flag competion at 11:59am 2012-12-10. First of all congratulations to all of you who succeeded in creating and submitting a commander for this phase!

All submitted commanders will now take part in an internal competition (no live updates of the results table) and we will post the results end of this week. Good luck to all participants!

Phase 2 around the corner

But there is more! End of this week we will announce the focus of phase 2 of the competition. We will make some gameplay/game mode changes with a focus on more strategic AI. Together with this we will launch video replay capabilities and other updates to the page. Stay tuned!

CTF Update 1.5 Release Notes

Alex J. Champandard — Thu, 06 Dec 2012 16:41:29 +0000

Capture The Flag SDK 1.5

This SDK release is available for Linux and Windows.

Gameplay & Interface

Field of view is now 60 degrees during defend and idle (90 for moving orders). Defend is intended to represent a more focused state, trading a smaller field of view for a faster shooting reflex.
Specified different order delays for if you are repeating an order (eg Charge order while charging) and specifying an order from idle. There is now a 1 second delay for re-issuing a defend command while already defending.
Issuing orders in padding areas previously would cause an error to be printed to the output and the bot to ignore the command, now it picks the nearest free node from the GridMapRegion
Added a warning if target position is inside a block or outside the level
Fix for bots shooting through walls.
Prevent shooting through diagonal wall of blocks.
Commands that are resumed after shooting no longer resume at beginning of target waypoint list.
Increased game time on all maps to 5 minutes.
Fixed map00 so that you can't cover the flag spawn positions from the bases.
Added a new map11 with tricky flag and return point placement, as well as three lanes.
Added a new map30 with crossing diagonals and relatively open play.
Fix for character respawning while still holding the flag (if they died holding it during the frame of a respawn)
Fixed instigator and subject properties of combat events. This should fix the problems people were seeing with the bot references not matching the bots in the team members lists.
Added LevelInfo.respawnTime to expose the number of seconds between bot respawns.
Added support in the network protocol version for LevelInfo.respawnTime. This does not change the network protocol version number sent during handshaking.
The simulate.py by default picks a random level. Levels are listed at the top of simulate.py.
Renamed the --map parameter of the simulate script to --level, to prevent clashes with built-in function 'map'.

Implementation

Added timeouts for the python network client and network server to handle dropped connections or unresponsive clients.
Fixed missing events sent to network clients. Previously we could miss events that occurred immediately before the tick was sent to the network clients.
Fixed bug during sending of large network messages sent to some network clients.

Python Client

Fixed network disconnects on linux with Errno 11 Resource temporarily unavailable.
Fixed the Python client so the combatEvents list does not nest lists, and is structured identically to non-networked clients.
Added **kwargs parameter to the python Commander __init__. Commanders with their own __init__ functions must call pass through the kwargs parameter.
Added optional --serverHost and --serverPort command line arguments to the python network client. If not provided the default is localhost:41041
Added an optional --name argument to the python network client. This is used for controlling the log file name.

The AI Sandbox 0.20.5

The AI Sandbox is is available for Linux (32 bit and 64 bit) as well as Windows.

Fix for the overlay in Ubuntu/Linux.

C++ Language Pack 1.2.1

This language package is available for both Windows and Linux.

Added support for the network protocol 1.2.1 (described above).
Fixed incorrect network shutdown in the C++ client
Extended the c++ wait time for initial connection to 10s

Java Language Pack 1.2.2

This language package is available for both Windows and Linux.

Added support for the network protocol 1.2.1 (described above).

Other Language Packs

Other community supplied language packs are listed on the Download page.

CTF Newsletter 2012/11/25

Alex J. Champandard — Sun, 25 Nov 2012 15:47:19 +0000

It's been quite an amazing start to the event and the last few weeks have been hectic — in a good way! There's even more in store, so we figured now's a good time for an update... Here goes, in no particular order.

1. Bugs & Other Problems

There's a small team working on the CTF competition full time, but we don't claim it's perfect (yet)! A few days ago, we've shipped version 1.4.x of the CTF SDK and have been fixing minor bugs since. The current version 1.4.2 on Linux, and 1.4.1 on Windows are reported to work perfectly. The corresponding AI Sandbox release 0.20.4 is only known to crash due to graphics driver issues, which we're trying to address.

If you have any issues or problems, don't hesitate to post them in the forums and we'll get back to you ASAP! We're also working towards open-sourcing the Python game code, but that will take a bit more time as our focus is on the online ladder right now.

2. Platform & Language Support

We launched the competition with only Windows support, added 64 bit Linux, and recently 32 bit Linux. We're also prototyping the OSX build, but can't say yet when that will be available. (In the meantime, the Linux version works great in virtual machines on Mac.) Download the latest versions here:

http://aisandbox.com/download

As far as programming languages are concerned, we launched with Python and our amazing community followed quickly with Go, Lua, NodeJS and Java clients; you guys are awesome! We also shipped the C++ starter kit. With the JSON API it's trivial to add new clients in other languages too! Also see the download page to get your hands on those, or if you'd like to help with other languages email us.

3. Gameplay Update & SDK

The latest update includes a small order delay to prevent micro-management. We'll tweak that delay to make it behave better when taking orders while idle, or taking the updates to the same order, but overall you should design your commanders to be able to deal with this. You can also customize your maps by editing the assets/map*.[png,ini] files, and we encourage you to do so! The next update will include more maps and different layouts to stress test your commander's AI.

We've also updated orders like the Defend order, to take multiple threat directions. The bot will then cycle between those various defend directions. We're also considering an Escort order and an Attack for moving targets, which may or may not be in the next release depending on the behavior of the submitted bots! Which leads to...

4. Submissions

We had early alpha submissions for testing, and we ran the first tournament manually. The ladder is now online and you can see the results live here:

http://aisandbox.com/rankings/

The full automated system should now be running smoothly, and can now submit your commander here. If you encounter any issues don't hesitate to let us know:

http://aisandbox.com/submit/

Python will be the first supported language, but upload any language at this stage and we'll add support by prioritizing the most popular languages.

5. Tutorial Replay

This weekend, Alex gave a more advanced tutorial about techniques specifically for the competition. We'll look at the types of 2D graphs available, and see what libraries can be used to perform tactical pathfinding, and other forms of terrain reasoning.

You can watch the replay by clicking on this link. (You can skip the introduction, 18:00 is the starting point.)

If there's anything else on your mind, or if you have any ideas that would improve the competition, don't hesitate to let us know!

CTF Update 1.4 Release Notes

Alex J. Champandard — Thu, 22 Nov 2012 14:24:26 +0000

Capture The Flag SDK 1.4

This SDK release is available for Linux and Windows.

There is a known issue with this release when using game.NetworkCommander to create a network game server. More information about this issue, including a workaround, can be found on the Known Issues page.

Gameplay & Interface

Added a delay between a bot receiving a new order from a commander and beginning to execute that order. This is currently 1 second. This is shown in the game as a salute animation.
The Defend order has been modified to allow a list of (direction, time) pairs to be passed as the facingDirection. The following syntax is now allowed for the defend order.
Defend(botId) # faces in the previous facing direction.
Defend(botId, Vector2.UNIT_X) # turns to face in 'direction'.
Defend(botId [(Vector2.UNIT_X, 1.5), (Vector2.UNIT_Y, 1.0)]) # faces in +ve x-direction for 1.5 seconds, then +ve y-direction for 1 second.
Times smaller than a minimum time (currently 1 second) are increased to the minimum time.
Turning is no longer instantaneous during Defend orders and while shooting
Bots resume their previous command if it was interrupted by them shooting at another bot. Resuming the interrupted command does not incur the time delay normally imposed when a bot takes an order from the commander.
New map added, map21.[png,ini] in the #/assets/ folder. To specify which map is played, pass --map to simulate.bat or modify simulate.py.

Implementation

Maps can have a corresponding .ini file that describes the team sizes, flag and bot spawn locations and the scoring locations.
Added a graphical representation for the team score location (the location a team must take an enemy flag to score) if it is in a different position to the team flag spawn location.
Re-added the ability to add a Vector2 and a float. This is equivalent to adding the float to each of the Vector2 elements. This was added to fix existing code that was using this behavior.
Bumped network protocol to 1.2 to support modified Defend order and additional combat events (flag restored event and bot spawned event)
Fixed pause at start of a network game while waiting for ready command from network commander.

The AI Sandbox 0.20.4

The AI Sandbox is is available for Linux (32 bit and 64 bit) as well as Windows.

Support for running on Windows XP. The AI Sandbox installer doesn't work on XP, the .exe should be manually unzipped and the game/run.bat file in the Capture The Flag SDK modified to specify the path where the AI Sandbox is extracted to.

C++ Language Pack 1.2

This language package is available for both Windows and Linux.

Changed the Defend facing direction to allow boost::none, a single facing direction, or a list of facing directions and the time spent facing each direction. If a list is provided the bot will cycle through the directions in the list.
Added support for the network protocol 1.2 (described above).

Java Language Pack 1.1

This language package is available for both Windows and Linux.

Added support for the network protocol 1.2 (described above).

Other Language Packs

Other community supplied language packs are listed on the Download page.