Class: Rule

Rule

(abstract) new Rule()

Rules define specific characteristics of each variant of the game. All rules should inherit from this base class and define the following properties: - Maximum number of points (usually 26 - 24 on board, one on bar, and one outside) - Maximum number of checkers (usually 15 per player/colour) and methods for: - Rolling dice (and a list of moves the player has to make after drawing a specific dice) - Reset state to initial position of pieces. - Validating a move - Checking if game has ended - Checking which player won - Checking how much points the player won
Source:

Members

country :string

Full name of country where this rule (variant) is played. To list multiple countries use a pipe ('|') character as separator.
Type:
  • string
Source:

countryCode :string

Two character ISO code of country where this rule (variant) is played. To list multiple codes use a pipe ('|') character as separator. List codes in same order as countries in the field above.
Type:
  • string
Source:

description :string

Full description of rule
Type:
  • string
Source:

maxPieces :number

The number of pieces each player has
Type:
  • number
Source:

name :string

Rule name, matching the class name (eg. 'RuleBgCasual')
Type:
  • string
Source:

title :string

Short title describing rule specifics
Type:
  • string
Source:

Methods

allPiecesAreHome(state, type) → {boolean}

Check if all pieces are in the home field.
Parameters:
Name Type Description
state State State to change
type PieceType Type of piece (white/black)
Source:
Returns:
- True if all pieces are in home field
Type
boolean

(abstract) applyMoveActions(state, actionList)

Call this method to apply a list of actions to a game state. Actions depend on rule and usually are `move`, `hit`, `recover` or `bear`.
Parameters:
Name Type Description
state State State to change
actionList Array.<MoveAction> List of action to apply.
Source:

bear(state, piece)

Bear piece - remove from board and place outside
Parameters:
Name Type Description
state State Board state
piece Piece Piece to bear
Source:
Throws:
Throws an error if there is no piece at fromPos or piece is of wrong type

calculateMoveWeights(state, movesLeft, pieceType, rootPiece, stopAtMax) → {Object}

Recursively try out all combinations for the specified player (by piece type) and check the "weight" of each combination. Weight is the sum of all piece movements for a particular combination of moves (called "branch")
Parameters:
Name Type Description
state State State
movesLeft Array.<number> Move values left
pieceType PieceType Type of piece (white/black)
rootPiece Piece Check only branches starting from a specific piece
stopAtMax boolean Stop calculation if a branch that allows all moves to be played has been found.
Source:
Returns:
- Map containing maximum weight for each branch, indexed by piece ID and total maximum weight for all branches, accessed with 'max' index
Type
Object

countAtHigherPos(state, position, type) → {number}

Count pieces of specified type at higher positions
Parameters:
Name Type Description
state State State to check
position number Normalized position (inclusive)
type PieceType Type of piece (white/black)
Source:
Returns:
- Number of pieces at positions higher than position
Type
number

(abstract) getGameScore(state, player) → {boolean}

Check game state and determine how much points the player should be awared for this state. If opponent player has not borne any pieces, award 2 points. If opponent has not borne any pieces, and still has pieces in home field of player, award 3 points. In all other cases award 1 point.
Parameters:
Name Type Description
state State Game state
player Player Player
Source:
Returns:
- True if player has won the game
Type
boolean

(abstract) getMoveActions(state, piece, steps) → {Array.<MoveAction>}

Call this method after a request for moving a piece has been made. Determines if the move is allowed and what actions will have to be made as a result. Actions can be `move`, `hit`, `recover` or `bear`. If move is allowed or not depends on the current state of the game. For example, if the player has pieces on the bar, they will only be allowed to recover pieces. Multiple actions can be returned, if required. Placing (or moving) a piece over an opponent's blot will result in two actions: `hit` first, then `recover` (or `move`). The list of actions returned would usually be appllied to game state and then sent to client. The client's UI would play the actions (eg. with movement animation) in the same order.
Parameters:
Name Type Description
state State State to change
piece Piece Piece to move
steps number Number of steps to increment towards first home position
Source:
See:
Returns:
- List of actions if move is allowed, empty list otherwise.
Type
Array.<MoveAction>

(abstract) hasWon(state, player) → {boolean}

Check game state and determine if the specified player has won the game. This method assumes that the specified player was on turn and has played and confirmed his move.
Parameters:
Name Type Description
state State Game state
player Player Player
Source:
Returns:
- True if player has won the game
Type
boolean

havePiecesOnBar(state, type) → {boolean}

Check if there are any pieces on the bar.
Parameters:
Name Type Description
state State State to check
type PieceType Type of piece (white/black)
Source:
Returns:
- True if there are any pieces on the bar
Type
boolean

hit(state, piece)

Hit piece - send piece to bar
Parameters:
Name Type Description
state State Board state
piece Piece Piece to hit
Source:
Throws:
Throws an error if there is no piece at fromPos or piece is of wrong type

(abstract) incPos(position, type, steps) → {number}

Increment position by specified number of steps and return an incremented position
Parameters:
Name Type Description
position number Position
type PieceType Type of piece
steps number Number of steps to increment towards first home position
Source:
Returns:
Incremented position (denormalized)
Type
number

initialize(state)

Initialize state.
Parameters:
Name Type Description
state State Board state to initialize
Source:

isMoveActionRestricted(state, movesLeft, piece, steps) → {boolean}

Checks if a specific move action is restricted. If there are any move combinations that would allow the player to use all dice values, then the player is obliged to use one of those combination. If playing both dice values are not possible and the player should choose which one of them to play, they must play the higher value (as long as it is possible).
Parameters:
Name Type Description
state State State
movesLeft Array.<number> Move values left
piece Piece Piece to move
steps number Number of steps to move
Source:
Returns:
- Returns true if move is restricted (not allowed).
Type
boolean

(abstract) markAsPlayed(game, move)

Mark move as played
Parameters:
Name Type Description
game Game Game
move number Move (number of steps)
Source:

move(state, piece, toPos)

Move piece to specified point, without enforcing any rules or performing any validation.
Parameters:
Name Type Description
state State Board state
piece Piece Piece to move
toPos number Position to which to move the piece to
Source:
Throws:
Throws an error if there is no piece at fromPos or piece is of wrong type

(abstract) nextTurn(match)

Proceed to next turn. Start next turn: 1. Reset turn 2. Change players 3. Roll new dice
Parameters:
Name Type Description
match Match Match
Source:

place(state, number, type, position)

Place one or more pieces from player set to board point.
Parameters:
Name Type Description
state State Board state
number number Number of pieces to place
type PieceType Type of pieces to place
position number Position at which to place piece(s)
Source:

recover(state, piece, position)

Recover piece - place from bar to board
Parameters:
Name Type Description
state State Board state
piece Piece Piece to recover
position number Position to which to place the piece
Source:
Throws:
Throws an error if there is no piece at fromPos or piece is of wrong type

(abstract) resetState(state)

Reset state to initial position of pieces according to current rule.
Parameters:
Name Type Description
state State Board state
Source:

rollDice(game, valuesopt) → {Dice}

Roll dice and generate list of moves the player has to make according to current rules. Descendants rules would normally override this method in order to properly determine the allowed move values that correspond to a specific die combination (eg. doubles).
Parameters:
Name Type Attributes Description
game Game Game object. Used to check if it is the first turn of the game.
values Array.<number> <optional>
 Optional parameter containing the dice values to use, instead of generating random values. Used by some rules as RuleBgGulbara.
Source:
Returns:
- Dice object containing random values and allowed moves
Type
Dice

validateConfirm(game, player) → {boolean}

Validate confirmation of moves. This is the base method for validation of moves that make a few general checks like: - Is the game started and is finished? - Is it player's turn? - Was dice rolled? - Are all moves played? - Not confirmed already? Descendant rules must extend this method and add additional validation checks according to the rule specifics.
Parameters:
Name Type Description
game Game Game
player Player Player
Source:
Returns:
True if confirmation is allowed
Type
boolean

validateMove(game, player, piece, steps) → {boolean}

Validate piece move. This is the base method for validation of moves that make a few general checks like: - Is the game started and is finished? - Is it player's turn? - Was dice rolled? - Are moves with values equal to the steps left? Descendant rules must extend this method and add additional validation checks according to the rule specifics.
Parameters:
Name Type Description
game Game Game
player Player Player requesting move
piece Piece Piece to move
steps number Number of steps to make forward to the first home position
Source:
Returns:
True if move is valid and should be allowed.
Type
boolean

validateTurn(game, player) → {boolean}

Validate player's turn. This is the base method for validation of moves that make a few general checks like: - Is the game started and is finished? - Is it player's turn?
Parameters:
Name Type Description
game Game Game
player Player Player
Source:
Returns:
True if move is valid and should be allowed.
Type
boolean

validateUndo(game, player) → {boolean}

Validate request for undoing moves. This is the base method for validation of undo that make a few general checks like: - Is the game started and is finished? - Is it player's turn? - Was dice rolled? - Are all moves played? - Not confirmed already? Descendant rules can extend this method and add additional validation checks according to the rule specifics.
Parameters:
Name Type Description
game Game Game
player Player Player
Source:
Returns:
True if confirmation is allowed
Type
boolean