Tag Archives: tafl open 2016

Tafl Open 2016: An Update

Unfortunately, turnout for the tournament ended up being rather disappointing. The only entrant to submit an entry was Jonathan Teutenberg, with J.A.R.L.

By the rules as written, this leaves him with the title of champion. Fortunately for you, dear tournament follower, I spoke with Mr. Teutenberg, and we agreed to a one-match playoff between OpenTafl and J.A.R.L.

You can expect to see that game on Monday, January 2nd, starting at about noon Eastern time. There will be coverage available in several forms: a liveblog here, a stream at my hitbox channel (I’ll provide a link when the time comes), and live viewing at a special OpenTafl multiplayer server.

To connect to that multiplayer server, go to Options in your OpenTafl client and change the server address to taflopen.manywords.press. (That server is not up yet; I’ll be starting it on Sunday night.) Connect to the server. (Note that accounts will not be transferred from the main Many Words OpenTafl server. Logging in with a new username and password will register a new account.) The game will be made available for spectators at about the start time.

Stay tuned later today for OpenTafl v0.4.5.0b, the version which will play in the tournament.

Tafl Open 2016 Contenders: J.A.R.L

The first submission to the 2016 OpenTafl Computer Tafl Open arrived in my inbox yesterday morning. Since I had not yet finished my coffee at work, I decided to open it up and extend my break a bit.

J.A.R.L was developed by Jonathan Teutenberg, who comes to us from the java-gaming.org forum (under the name Jono). It’s a fairly standard iterative deepening depth-first search player, the same structure as OpenTafl’s AI, with two fascinating features.

First, it uses as a component in its evaluation function the distance to a king victory in a simple abstraction of the game. In the simplified version, only the king is allowed to move, and he can move through pieces with a move count penalty. The score is a combination of the abstract distance to each corner, the material balance, and the freedom of the king’s men.

Second, it does some advanced pruning of the search tree, along with some move ordering. Moves which make or avoid captures are weighted heavily and searched more deeply, while states which are much worse than alternatives and worse than the current position are not expanded.

The upshot is an AI which seems to have no small measure of strength to it, enough so that a game against it was worth commenting on, to some degree. (Granted, only because it lost a particular corner endgame I’ve seen come up before.) My suspicion after one game is that it’s one of the best AIs for the attacking side I’ve played to date. I look forward to seeing it in action in the tournament.