Help For the Game Of Antipod
Welcome to the network Antipod server. The Antipod challenge command is described here. Other commands are the same as for all pbmserv games.
antipod challenge [-radius=number] userid1 userid2
Start a new game between userid1 and userid2.
The -radius parameter sets the number of points along each edge of the board. The valid range is 4..10 with 6 being the default.
Two players, White (o) and Black (x), take turns placing a piece of their colour on either the left board or the right board. Pieces connect with adjacent neighbours, as in Hex. Any piece placed on a board edge belongs to both boards at once, and a duplicate piece is placed on the corresponding point of the other board to show this. This allows the connection to pass continuously from one board to the other.
Black wins by connecting the two boards' central points with a chain of 'x's. White wins by preventing this, i.e. by completing a ring of 'o's around at least one of the central points. Draws are not possible.
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Each game starts with two target points 'x', and an 'o' in each of the six equatorial corners to balance Black's inherent advantage. White (o) plays first.
Antipod models the connection of antipodal points upon a sphere, where the left and right boards represent the two halves of the sphere. Duplicated edge pieces are really just two views of the same piece from different sides of the sphere, and are not necessarily any stronger than non-duplicate moves.
This is not a perfect hexagonal mapping on the sphere; the six equatorial corner points only have four unique neighbours each.
Smaller board sizes favour Black while larger board sizes favour White. We are still experimenting to determine the optimal board size.
The following example shows a game won by Black, who has connected the central
point of each board with a chain of 'x's.
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Black's winning path may not be immediately obvious as it jumps from board to board several times.
The move syntax is:
antipod move board userid password coord
Where coord is of
In all cases the point must be vacant. Any piece placed at an edge point is automatically created on both boards, and the move marked with a '+' in the move list.
References and History
Antipod rules copyright (c) 2003 Cameron Browne.
Antipod was invented following discussions with Bill Taylor regarding projective Hex games (games of connection which continue across board edges). Antipod's method of edge piece duplication has the advantage of explicitly showing edge crossings on both boards, making the game more comprehensible to the player than some others of this class.
Antipod was originally named Corpus Callosum for obvious reasons.
Implementation and help file by Cameron Browne, September 2003.