Adding dice to the board

Dice can be set up and added to the board by selecting dice values from the dropdown lists marked "left die" and "right die" (under the "Cube problem" button). Note that you cannot set dice if the "Cube problem" button is set on (shows a green tick). If you set dice, you must set both — if only one die is set, both will be ignored and reset. The dice are placed according to the player on roll. Once you have set the dice you want, click once on the "submit" button at the bottom right of the GABBI window. This will cause the form elements to be read and the board will be redrawn, complete with dice. If you wish to ensure no dice are displayed, set both dice to the default "-" symbol.

Default — no dice are shown.

Setting the cube value and position

Display of the doubling cube will be on or off according to thebutton. If this button is off (shows a red cross), the cube will not be displayed and the cube value and cube location fields immediately below it will be grayed out. The cube can be placed at the top, centre or bottom of the board and it can have a value of 1,2,4,8,16,32,or 64.

Note: If the cube is not in the centre, its value must be 2 or more or it will be reset.

Defaults — Show Doubling Cube is on, Cube value is "1", Cube location is "centre".

Setting up a cube problem

You can set up a cube problem by clicking once on thebutton. This changes the display and location of the cube and introduces a Cube-Arrow-Cube image which is called the CAC device. If the cube is initially in the centre of the bar or set to a value of "1", the CAC device will contain a short arrow, with the first (initial) cube placed in the centre of the board and connected to the new cube which is placed nearest the player being cubed. If this is a re-cube, ie one of the players already owns the cube, the CAC device will have a long arrow, with the current cube value nearest the player cubing and the doubled cube value nearest the player being cubed.

Note: The CAC device has some intelligence — it will move around the board if there is not enough room to display it without overlapping checker stacks. By default, it will try to appear centred in the half of the board containing the "home" boards. If it cannot find space in the home (inner) board, it will move to the outer board. If all else fails, the CAC device will end up on the bar.

Default — "Cube problem" is off.

Setting the match score

Under the "Show labels" button is a radio button labelled "money" or "match". Setting this to "money" will disable the match length and score fields immediately below. If it is set to "match", you can enter a match length between 1 and 99 and scores accordingly. Any scores entered must be less than the match length of course. Invalid scores will be reset to 0. Click on the "submit" button after setting the score.

Defaults — Match Length is "7", both player scores are "0".

Adding player names

Player names can be assigned to each side. Player names do not affect the board itself, or the match information. They are only displayed at the bottom of the board in the text label area if the "Show labels" button is checked. Note that swapping colours does not swap player names. If you want to swap player names you need to re-enter the names in the form section above the board diagram. Names can be a maximum of 20 characters long.

Defaults — Player names are set to "Player0" and "Player1".

Using the Crawford flag

The Crawford flag signifies match point for one player and means that no cubing is allowed in this game. If it is set, the "Show cube" button is set to off (shows a red cross) which prevents cube data being entered. You need to click on the "submit" button after setting the Crawford flag. If one of the player scores is not match point (ie match length -1) the Crawford flag will be ignored and reset to Off.

Default — Crawford flag is off.

Setting the display of pip count, point numbers and text labels

There are three more buttons on the right of the GABBI window:

The pip count for each player is displayed above and below the bar of the board. If you do not wish to see the pip count, click once on "Show pip count" — the button will change from containing a green check mark to one with a red cross and the board display will have the pip count removed.

Point numbers are used when describing backgammon plays and are a useful visual aid. Point numbering will change according to the direction of play and whose turn it is. You can prevent the display of point numbers by clicking on "Show point numbers".

The text labels consist of three lines of text; at the top (above the board diagram) is the gnubg Position ID and Match ID of the current board. Under the board are two more lines which describe the match scores, turn, dice and other information. Display of this data can be turned off by clicking on the "Show labels" button.

Defaults — all these buttons are set to "on".

Note: You can quickly reset all the form elements to their defaults by pressing thebutton at the bottom right of the GABBI window.

Importing and exporting to/from gnubg

• V1_01 update: GNUBg 0.90 has combined Position ID and Match ID into GNUBg ID which is now supported by GABBI.

The match information can be compressed into a convenient format called the Match-ID. It is a 12 character code similar to Position-ID (see previous section) and will change whenever match data is changed or added. Match data can be imported from gnubg by copying the Match-ID into GABBI and pressing the "submit" button next to the Match-ID field. You can submit Match-ID and Position-ID together or separately — they are both read when the button is pressed. Entering a gnubg match-id will overwrite the current form data.

If you'd like to know how gnubg Position ID and Match ID are constructed, click here:

http://www.gnu.org/software/gnubg/manual/html_node/Technical-Notes.html#Technical-Notes

and then click on the appropriate link.

Importing and exporting to/from eXtreme Gammon

• V1_02 update: New feature!

Positions can be imported or exported to/from Extreme Gammon using the XGID code. The XGID is a string of text which contains all the information required to construct a backgammon position and match information. It works in a similar manner to gnuBgID.

Importing

In eXtremeGammon, press <ctrl><shift>c to copy the current position, move to your GABBI window, select the field marked Xg ID and paste the id into the box with <ctrl>v. You must then press the "submit" button to enable GABBI to create the diagram.

Exporting

When you've finished editing your board in GABBI, select the XGID code from the field marked Xg ID using <ctrl>c, then move to your eXtreme Gammon window and press <ctrl>v. It's as simple as that!

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© Simon Woodhead 2008-2010. All rights reserved.