## Help for the Game of Trilbert

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

trilbert challenge [-num_tiles=number] [-win_largest|-lose_largest|-no_largest] userid1 userid2

starts a new game for two or three players.

The -num_tiles parameter specifies the maximum number of tiles (default no limit).
The -win_largest option specifies that the player with the largest group when the tiles run out wins.
The -lose_largest option specifies that the player with the largest group when the tiles run out loses (default).
The -no_largest option specifies that the game is drawn when the tiles run out.

### Introduction

Trilbert is boardless strategy game for two players. Players takes turns adding pieces called trilberts; the aim is to form a loop of your colour.

Each trilbert is like a jigsaw piece with four arms, with each half coloured a different player colour:

```         _---_                   _---_
/     \                 /     \
|       |               |       |
\     /                 \     /
|   |                   |   |
|   |       _---_       |   |
/     \_   _/     \_   _/     \
|        ---         ---        |
|                               |
\_    __---_       _---__    _/
----      \     /      ----
|...|
_----__   _/.....\_   __----_
/.......---.........---.......\
|...............................|
\......_---_......._---_....../
|..../     \_..._/     \....|
|...|        ---        |...|
/.....\                 /.....\
|.......|               |.......|
\_..._/                 \_..._/
---                     ---    ```

### Rules

To start, a trilbert is placed on the playing surface.

Players then take turns adding a trilbert to extend the existing group. Trilberts can only be placed where they would be held securely by existing pieces and not move unless lifted out. For instance:

```        x---x   o---o
o       o |   |
|       | x---o
o---o---o |   |
| x---x   o---o
x---x---x
|       |
x       x```

Players win by completing a loop of their colour. The loop may pass through touching pieces of the same colour but may not jump across gaps. The enclosed region may be empty or occupied by enemy pieces. If this is achieved simultaneously for both players then the game is a draw.

For example, the following position shows a winning loop for X:

```        o       o
|       |
o---o---o
|
x---x---x
o---o | x---x | x---x   o---o
| x | o   x   o |   |
o---x |       | x---o
|   | o---o---o |   |
o---o   x---x | x---x   o---o
x---x---x
|       |
x       x```

If the tiles run out before either player wins, then the player with the largest connected group loses.

### Syntax

The move syntax is:

trilbert move board# userid password b13

Place tile rotation b at move position 13.

### History

Trilbert pieces and rules copyright (c) Cameron Browne, December 2007.

More details are available at the official Trilbert page.

The name "trilbert" is a contraction of "Truchet Hilbert", as the piece shapes are actually a mathematical curves called Truchet contours and the H-like motif is reminiscent of the Hilbert curve generator.

Implementation and Help file by Cameron Browne, December 2007.