[pbmserv] New game: Star

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

Star is a famous connection game by Craige Schensted, and is widely thought 
to be one of the deepest of this group of games. Players try to connect as 
many edge cells with as few chains as possible.

Maxi-Star is also included as an option.

camb

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Help For the Game Of Star

Introduction

   Welcome to the network Star server. The Star challenge command starts
   a new game between userid1 and userid2. Other commands are the same as
   for all pbmserv games.

       star challenge [-size=number] [-maxi] userid1 userid2

   The -size parameter sets the board size in the range 3..14 (default =
   6). This number describes the number of cells along each of the
   board's three longest sides.

   The -maxi parameter specifies that Maxi-Star scoring is used
   (explained below).

Rules

   Star is played on the following board. Note that the sides alternate
   short/long around the board..

           1-   . . . . .
          2-   . . . . . .
         3-   . . . . . . .
        4-   . . . . . . . .
       5-   . . . . . . . . .
      6-   . . . . . . . . . .
       7-   . . . . . . . . .
        8-   . . . . . . . .   \
         9-   . . . . . . .   \ J
         10-   . . . . . .   \ I
                            \ H
                 \ \ \ \ \ \ G
                  A B C D E F

   Players takes turns placing one of their pieces on the board. Players
   may pass.

   Each chain of a player's pieces that touches an edge scores 1 point
   for every external cell it touches minus 2. The player's overall score
   is the total score of all of their chains.

               ? ? ? ? ? ?
              ? . . o o . ?
             ? . . . o . . ?
            ? . . . . o . o ?
           ? . . . . . o o . ?
          ? . . . . . . o . . ?
         ? o . . . . . o . . . ?
          ? . . o . . . o . . ?
           ? . . o . . . o . ?
            ? . . . . . . o ?
             ? . o . . . o ?
              ? ? ? ? ? ? ?

   For instance, the external cells are marked ? in the above example.
   Note that corner cells have three external neighbours and edge cells
   have two external neighbours.

   Player O has scored:
      + 1 for the single corner piece (3 external neighbours minus 2)
      + 0 for the double interior chain (no external neighbours)
      + 0 for the single edge piece (2 external neighbours minus 2)
      + 7 for the large chain (9 external neighbours minus 2)
     ------------------
      = 8 points total
     ==================

   The game ends when both players pass in succession, and the player
   with the highest score wins. Due to the design of the board there will
   always be an odd number of external neighbours hence draws are not
   possible.

   Maxi-Star: As above except that each players' score is the score of
   their best group. Games can be tied in this variant, in which case
   players' second best, then third best etc chains are compared to
   determine the winner (tie-breaker not implemented yet).

Move Syntax

   X moves first. The move syntax is:

       star move board# userid password coord

   Where "coord" is an empty board point in the form 'F6'.

       star move board# userid password pass
       star move board# userid password --
       star move board# userid password -

   Pass this turn. The game ends when both players pass in succession.

       star move board# userid password swap

   Swaps the opening move (second move only).

   Other commands are the same as for all pbmserv games.

History

   Star was invented by Craige Schensted.

   Maxi-Star rules by R. Wayne Schmittberger.

   Implementation and help file by Cameron Browne, December 2003.