twixtbot

Code for AI to play the board game Twixt

Requirements

The code is written with tensorflow 1.12 and python2 and runs on linux. I know all the cool kids use tensorflow 2.2 and python3 nowadays. Sorry!

How to Play!

Um... so the bad news is there is nothing plug-n-play here. Maybe some enterprising soul can turn this into an app that someone who doesn't want to fight with code can just turn on and play. What I can give you is the brief outline.

I first run a nns.py (Neural Net Server) with

./nns.py -m ../models/six-917000 -l /tmp/loc1 > out1 2>&1 &

Here -m gives us a pointer to the TensorFlow model, I have given you my best one. As we have seen from results on Little Golem, it can probably be improved with more training and/or a bigger net. -l is the "location" which is a combination unix socket and shared memory.

Now, if you want to get a smart move, you use the magic one.py program, example:

./one.py -m v19,r19,t18,p13,n13,m9,i9,k17 -t asn_player:trials=50000,location=/tmp/loc1 -T

Here -m gives a list of comma separated moves (swap is a legal move too), -t tells us what thinker we want to use. asn_player is the Asynchronous Net Player (I use nnmplayer for training runs), and trials is the amount of time to spend; on my computer it takes approximately 1 minute per 10000 trials. Even a very low number like 200 gives quite a strong opponent and is much faster. location you will recall from the nns.py command.

Other files

I don't remember what all of these do. The biggies are:

• battle.py which you use if you want to test two nets or configurations against each other
• bcount.py which is nice if you use battle.py in conjunction with pmany.py
• mkbig.py creates a raw, untrained net
• naf.py is a bunch of code to convert twixt positions to numpy arrays and back
• nnclient.py, nns.py, smmppy.py - these three files work together to create a "neural net server". This is especially useful during the part of training where you are self-playing, because it is important both to batch up your queries and also python sucks at threading.
• nnmcts.py, nnmplayer.py - these two files work together to make the synchronous player. Note you can use nnmplayer with one or battle with the model: option if you don't want to set up a nns server.
• one.py - as explained above, this is great if you want a bot player to give you a single move.
• pmany.py - a super handy python script to let you run a zillion copies of the same program. For example, during self-play what I do is set up a single nns.py and then around 80 battle.py with nnmplayer bots set to add 25% random noise (as per the Alpha Go stuff) all connecting to the same server.
• swapmodel.py - instead of writing code to MCTS the swap rule, I just played the bot against itself a few hundred times with each starting move, figured out whether white or black wins, fit a (almost) linear model to it, and there you go.
• train.py - runs a round or two of training on the neural net.
• twixt.py - twixt.Game is a super handy class for representing the state of a game of twixt.
• scripts - ugh, I barely remember what any of these do. You can see some stuff relating to AWS; what I'd do is rent several of the cheapest possible box with a GPU on it, run self-play games, and then download the output of those games to my home computer with manly GPUs to run actual training.
• web - believe it or not, this is an almost working web page where you can just come in and play a game of twixt against the bot.