DAG-Tournament

Introduction

DAG-Tournament, where DAG stands for directed acyclic graph, is a graphical program to manage an informal tournament of games such as foosball. It is designed for open-for-all tournaments without schedule, for example to record all games as they happen in the free time program of a serious event, such as a conference.

Games can be entered as they happen. The program does not generate a complete ranking, but only visualizes what it knows about who is better than who based on direct comparison, or a path of direct comparisons. Cycles are broken at the edge of least significance. The visualisation is baesd on springs and forces and updated in real time, already producing entertaining effects.

DAG-Tournaments supports more than one tournament at the same time, e.g. foosball and pool billard, and can switch between the two rankings with one keypress, again showing an entaining shuffling of nodes until a stable state is reached again.

Using

DAG-Tournament has no configuration file and takes no command line optins. Only if you want to handle more than one game at a time, you need to pass the names of the games as command line parameters. $ DAG-Tournament or $ DAG-Tournament Foosball Billard

At first, the screen will be blank, because no players or games have been added. You can now interact with the game in these ways:

Double click Add a new player. You will be asked for the name of the player.

Drag’n’drop one player onto another Add a new game result. You will be asked for the final score. If your game does not have scores, just enter 1:0.

Tab Switch between games, if you have more than one.

Hold shift Show the number of games per player. Useful to decide who ought to play next.

These are sufficient to use the program. Additionally, there is functionality meant to be used by the tournament organizer:

Ctrl-R Re-set the position of the players. If the nodes are in a somehow stuck and you expect that they are not yet in their optimal position, this puts them all into a straigt line, possibly allowing them to find a better possition on the screen.

Ctrl-E Edit the game state. This opens a text edit window with the list of players and games as a raw Haskell value. Here you can edit mistakes. If the result does not parse, it will be discarded, so edit with care!

After each change to the game state (adding a new player, adding a
game result, or using Ctrl-E), it is written to
~/.DAG-Tournamet.backup. If you need to resume the program, e.g.
after an accidential close or a crash, you can paste the contents
of that file to the edit window provided by Ctrl-E

Explanation of the screen contents

Player names are sometimes coloured. These colours mean:

Red Currently hovered by the mouse. All games with this players are shown on the left. Blue Start of a drag action. Let go of the mouse above another player to enter a game. Yellow A player that has already played at least against once against the player marked in red. Useful to find out who he has not yet played against.

The back arrows, usually pointing down, indicate that at the current standings, the upper player is better than the lower, either by direct comparision or a series of comparisions with intermediate players. Only a minimal amount of arrows are shown. So if there is an arrow from A to B and from B to C, there will not be an arrow from A to C, independently of whether A and C have played each other.

Credits

DAG-Tournamet is © 2009 Joachim Breitner and published under the terms of the GNU General Public License, Version 2 or later.