GNU Backgammon is a fun backgammon game, match and position analysis tool, statistical estimator and random generator based on a neural network.
It can serve you as an application to use when you want to kill some minutes of your free time playing the wonderful game of backgammon, or improve your playing strength through game analysis and playing against a very strong engine.
Playing the game
I suppose that everyone knows how to play backgammon, but let me explain real quick in case some of you don’t.
You start the game with a standard setup of 15 chips placed in a specific way on the board. The goal is to move all your chips to the bottom right side (as you look at it) of the game table. You can achieve this by rolling the dice and moving a chip for as many points as the dice number shows. For example if you roll a three and five, you will be able to move a chip three or five or eight points to the forward direction as shown in the below picture. Note you can’t move a chip backwards.
If you roll the same number with the two dices like two fours for example you can play the numbers twice. This means that in this case you would play four times four using your movement points for up to four different chips.
If a chip is standing alone in a point it can be hit. This means that if another chip of the enemy lands there the lone chip will leave the table and stand on the middle waiting to comeback in from the initial position spacing (example positions here from 19 to 24) using the dice again. You can’t land a chip when a position is occupied by two or more enemy chips.
The game ends when you have collected all your chips from the board. To do that you will first have to gather them all in your bottom right side (positions 1 to 6) and then take them using the dice again. If you roll a six and three for example you will remove from the board the chips that stand to the positions 3 and 6.
In GNU Backgammon you can play using many different options. Let’s just begin by taking a look at the defaults.
This is the initial screen. You can start a new game from the corresponding button on the top left, or edit a position placing the chips the way you want for analysis purposes. After you start a game you can roll the dice by clicking your mouse on the center of your side of the table. You then move the chips either by clicking them, or by draging them. When you grab a chip, a highlighted position will appear showing you the possible landing positions according to the dice roll.
You can resign, end game, accept or reject a doubling proposal, or offer your own at any time of the game by simply pressing the buttons on the middle. You can also choose to play against a human opponent, use manual dice or play in tutor mode that will help you understand the game better and improve your playing strength.
Making it look nicer
I know that you don’t like what you see so far so lets make the board look nicer and more realistic.
First simple thing to do is turn on the 3D view from the “View” menu and you’ll get this:
Then we can enable some more performance reducing stuff like shadows and smooth animations. There is also a big collection of different woods and backgammon sets waiting for you to discover.
After you are done with enabling things you can go fullscreen from the “View” menu again, and get a realistic, animating and shadowed backgammon board like this one:
A lot better don’t you think?
The GNU Backgammon engine can play in 8 pre-set different levels or tuned by the user to the desirable playing strength. Depending on its parameters and its luck in recent games, it rates from around 1900 to 2000 on FIBS, the First Internet Backgammon Server — at its strongest, it ranks in the top 5 of over 6000 rated players there) and is gradually improving.
GNU Backgammon is a fantastic analysis tool for those of you who need it. It can evaluate any position, perform a race analysis, calculate rollouts, show the distribution of rolls and a ton of more things…
You can also change the luck or skills settings of the analysis to get different decision or evaluation results from the engine.
The luck factor
True randomizing is a fundamental problem for every machine out there. GNU Backgammon tries to offer many options that include a big randomizing depth, while also offering some options that can manipulate or override completely the factor of luck.
These are the available random number generators:
- Blum, blum and shub
- Mersenne Twister (default)
- Read from file
You can set the application to override all this and roll specific things like the best or the worst roll, or even the 7th best or the second worst. Why would someone do that? For special analyzing purposes I suppose.
Being a serious backgammon tool, GNU Backgammon offers many options to play with. For example you can change the cubing rule and use Crawford or Jacoby. You can play clockwise or even use a Nackgammon starting position!
Whether you are a backgammon professional, or just a casual player GNU Backgammon is definitely worth your attention. It is a fantastic analysis tool, and a nice game to spend some time on.
There is only one thing I have to warn you about really. Playing against “grandmaster” level can cause serious frustration to an amazingly excessive degree. Even if you are a calm and balanced person, the grandmaster level will really test your patience.