Kropki (GM[40])

General info

As Kropki is very similar to Go, most of the conventions for Go remain valid. The main difference is that in Kropki there is an additional move: 'stop'.

Move, Point & Stone type

In Kropki the Stone (in Kropki called 'dot') becomes Point and
it consists of two letters. For Kropki it is important to have boards larger than 26x26 (30x30 is one of the most popular), hence we use both lowercase and uppercase letters, see below.

[coordinates (TA2.gif)] Coordinate system for points

The first letter designates the column (left to right), the second the row (top to bottom). The upper left part of the board is used for smaller boards, e.g. letters "a"-"m" for 13*13.
Using lowercase letters only the maximum board size is 26x26.

In FF[4] it is possible to specify board sizes upto 52x52. In this case uppercase letters are used to represent points from 27-52, i.e. 'a'=1 ... 'z'=26 , 'A'=27 ... 'Z'=52. (Note that there should be NO sgfs prior to FF[4].)

Moves

Moves without a stop are encoded just as in Go, for example W[ab] means that White puts a dot on the point 'ab'. Stops are encoded by a dot and then a sequence of points that form the border of the stop, with the end point the same as the start point. Examples:

Stop sequence

A sequence of points encoding the stop should satisfy the following conditions: The stop sequence is the dot '.' followed by the sequence of points as above. Example: ".cecfdgefdece".

Properties

Note that TW and TB may be used in two ways: as in Go, or in a Kropki-specific manner. When used as in a Go, TW and TB points must be unique, i.e. it's illegal to list the same point in TB and TW within the same node.
Property:	TB
Propvalue:	elist of point
Propertytype:	-
Function:	Specifies the black territory.
		Points must be unique.
                This is the way of using TB as in Go, unused yet.
Related:	TW

Property:	TB
Propvalue:	at least one stop sequence
Propertytype:	-
Function:	Specifies the border(s) of black pools.
                This is the Kropki--specific way of using TB.
                Example: TB[.cfdgefdecf.ggghhiihjgifhfgg]
Related:	TW

Property:	TW
Propvalue:	elist of point
Propertytype:	-
Function:	Specifies the white territory or area (depends on
		rule set used).
		Points must be unique.
                This is the way of using TB as in Go, unused yet.
Related:	TB

Property:	TB
Propvalue:	at least one stop sequence
Propertytype:	-
Function:	Specifies the border(s) of white pools.
                This is the Kropki--specific way of using TW.
                Example: TW[.cfdgefdecf.ggghhiihjgifhfgg]
Related:	TB