MetaBoard is a framework for board games that models the core components of many classic games like Pacman, Tetris, and Minesweeper. The framework represents games as a board space with items that move according to rules, similar to a board game played with physical pieces. It defines common player roles like moving pieces and tracking game state, and allows new games to be created by subclassing components like boards, pieces, data, and directors that orchestrate the game flow. Examples show how Pacman, Tetris, and Minesweeper could be implemented using the core framework components of players, boards, data, and directors.

1. MetaBoard: a framework for board
games.
By Laura Risani (alias) with the
collaboration of Stéphane Ducasse

2. Motivation
Games like
•PacMan
• Tetris
•Sokoban
•Snake
•Miner
•SameTile
•Atomic
•BoulderDash
A tiled space through which pieces are moved
according to some rules

3. Boardician’s design metaphor
There is a board on a table, a post-it of game data
attached to it, players sitting around and a director
standing.
He says 'play' successively to each of them and, as a
consequence, they according to their thoughts (play-
conditions) modify other players' thoughts by saying
things to them and modify the board/post-it with
their hands.

4. board
data
play-
conditions
#play
director
player
player
player
player

5. BGPlayer
BGDirector
BGData BGUserInterface
BGBoardSpace
BGBoardPlace
BGWall
BGFloor
BGMovableItem
BGSteadyItem
<PlayCondition>
BGBoard
BGPosition
*
*
*
*
BGHuman
BGPointer

6. •BGPlayer : action of modifying game’s board/data/players'
play-conditions when
1. receiving #play
2. receiving other msg to do some work related to its
playing purpose
Tell #nextPlayer.
•<PlayCondition> : anything that conditions how a player
behaves when receiving #play (like
BGDirection : BGDown, … ;
BGPlayState : BGOver , BGPaused, … ;
BGUserInput: BGClick, BGKeyStroke). Not necessarily directly
known by the player.
•BGHuman : action of modifying (…) because of user input.

7. •BGDirector : action of directing game flow. Initialize and
know the things that made up the board game. Loop while
game not over : decide who plays next, send him #play.
•BGBoard : board’s space and items placed at it.
•BGData : game data that doesn't belong to any particular
object (like lives, score, ... )
•BGUserInterface : handling of user input/output.
•BGFloor can hold any type of BGBoardItem
(BGMovableItem, BGSteadyItem), while BGWall doesn’t
accept any

8. A possible workflow
To implement a game with the framework
1. Define game's director (subclass of BGDirector) and
then define/implement successively what is needed
in each msg sent from within BGDirector's msg
#initialize.
2. Run game sending 'BGDirectorSubclass new play'
and adjust details according debug windows.
3. Add enhancements (menu, settings, … )

9. Example : Mines (MI-)
BGFloor
MIBoard
MITile
MIMine MINumber MIVoid
BGBoardSpace
MICoverState
MICovered
MIUncovered
MIFlagState MIFlagged
MIUnflagged
BGBoard
*

10. BGData MIData
BGPlayer
MITileAction
BGHuman MIHuman
BGDirector MinesGame
•MIData: mines left, seconds spent playing.
•MITileAction: action of doing something on a tile (toggle flag /
uncover) and carrying on its consequences. It’s play-conditions are
the pointed MITile’s MICoverState and MIFlagState.
( 1° )
( 2° ) MICoverState
MIFlagState

11. Example : Tetris (DP-)
BGSteady
Item
DPBoard
DPSquare
DPPiece
BGBoard
BGMovable
Item
DPPieceLayout
*
BGData
DPData
•DPData: number of completed lines.

12. BGPlayer
DPPieceMover
BGHuman DPHuman
BGDirector TetrisGame
•DPPieceMover: action of moving current piece. It’s play-condition is
aBGDirection.
•DPPieceDropper: action of dropping current piece (if not bottomed
periodically drop it, if bottomed add it to board and drop a new one).
It’s play-conditions are aBGTimedState and the BGPosition of the
board where new pieces are first dropped)
( 1° )
( 2° )
BGTimedState
BGDirection
DPPieceDropper
( 3° ) BGPosition

13. Example : Pacman (E-)
BGBoardSpace
BGFloor
BGMovableItem
BGSteadyItem
EBoard
*
*
EEater
BGBoard
EBiFloor
ETeletransporter
ETriFloor
EDirectedFloor
EBullet
EBigBullet ESmallBullet
EScoreItem
EMonster
BGData EData

14. BGPlayer
EEaterMover
BGHuman EHuman
BGDirector PacmanGame
( 1° )
( 2° )
BGTimedState
BGDirection
EMonsterMover
( 3° )
EScoreItemPlacer
( 4° )
BGDirection EAttitude
EVulnerability
EMoveConseq
uencer
, ,
EPositionSituation
EEaterAtBullet ,
EEaterAtEmptyFloor ,
EEaterAtMonster ,
EEaterAtScoreItem ,
EMonsterNotAtEater

15. •EData: lives, score.
•EMoveConsequencer : action of carrying on consequences of
moving an EEater / EMonster. Play-conditions: BGPosition,
EEater/EMonster , EPositionSituation subclasses.
•EEaterMover : action of moving an EEater and carrying on
consequences. Play-conditions: BGDirection.
•EMonsterMover: action of moving an EMonster and carrying on
consequences. Play-conditions: BGFloor subclasses, BGDirection,
EVulnerability, EAttitude.
•EScoreItemPlacer : action of placing/displacing a EScoreItem on the
board. Play-conditions: BGTimedState.

16. Other example games : Sokoban, Snake, SameColor.
More info at
http://boardician.blogspot.com/2015/07/metaboard.html
Questions? Comments? Suggestions? Mail me at
laura.risani@gmail.com
Thank you !
<3