[pbmserv] New game: Orbit

[Cameron Browne <cameronb@optusnet.com.au>]

Orbit, a nice Go variant by Steven Meyers, has been added to the server.

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Help For the Game Of Orbit

Introduction

   Welcome to the network Orbit server. The challenge command is
   described here. Other commands are the same as for all pbmserv games.

   orbit challenge userid1 userid2 [userid3..5] [-size=S]

   Starts a new game between userid1, userid2... up to five players.
   The -size option specifies the board size in the range 3..19 (default
   is 13).

Rules

   Orbit is a Go variant in which players strive to enclose territory
   inside orbits and half-orbits.

   An orbit is a cycle of same-coloured pieces that encloses one or more
   points. A half-orbit is a connected set of pieces that, together with
   one side of the board, encloses one or more points. The enclosed
   points may be empty or occupied by enemy pieces. The surrounding
   connection may include orthogonal and diagonal steps.

   The following example shows an O orbit and two X half-orbits:

     A B C D E F G H I

  9  - - - - x - - x -  9
  8  - - - - x x - x -  8
  7  - - - - - - x - -  7
  6  - - o o - - - - -  6
  5  - o - - o - - - x  5
  4  - o - - o - - x -  4
  3  - o - o - - x - -  3
  2  - - o - - - - x -  2
  1  - - - - - - - - x  1

     A B C D E F G H I

   Players take turns placing a piece of their colour on any empty point,
   provided that point does not lie within an enemy orbit or half-orbit.
   After each move, enemy pieces enclosed by orbits are captured and
   removed from the board.

   The game ends when either the board fills up or all players pass in
   succession. The player with the most territory wins; territory is the
   total number of empty points exclusively within that player's orbits
   and half-orbits (shared territory does not count).

Syntax

   orbit move board# userid password g4
   orbit move board# userid password swap (third move only)
   orbit move board# userid password pass

References and History

   Orbit was designed by Steven Meyers.

   Implementation and help file by Cameron Browne, February 2005.