Board class

Represents a Go board state and operations.

The board is stored as a 2D list state[y][x] where null means empty, and Stone.black/Stone.white represent stones.

Note:

  • The constructor does not defensively copy the provided state. If the caller mutates it afterwards, this Board will observe the change.
  • set and clear mutate this instance. makeMove returns a cloned board with the move applied and does not mutate this instance.

Constructors

Board(List<List<Stone?>> state, {Map<Stone, int>? captures, KoInfo? koInfo})
Creates a board from an existing state.
Board.fromDimension(int width, [int? height])
Creates an empty board of size width×height (square if height omitted).

Properties

hashCode → int
The hash code for this object.
no setterinherited
height → int
no setter
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
state ↔ List<List<Stone?>>
Two-dimensional board state state[y][x]. null represents an empty point.
getter/setter pair
width → int
no setter

Methods

clear() → void
Resets the board to an empty state (keeps dimensions).
clone() → Board
Returns a deep copy of this board.
copyWith({List<List<Stone?>>? state, Map<Stone, int>? captures, KoInfo? koInfo}) → Board
Returns a new Board with optionally replaced state, captures, or koInfo.
diff(Board board) → List<Vertex>?
Returns the list of coordinates that differ from board, or null if sizes differ.
get(Vertex vertex) → Stone?
Returns the stone at vertex, or null if empty or out of board.
getCaptures(Stone player) → int
Returns the number of stones captured by player.
getChain(Vertex vertex) → List<Vertex>
Returns the connected component (chain) of same-colored stones containing vertex. If vertex is empty or out of board, returns an empty list.
getConnectedComponent(Vertex vertex, bool predicate(Vertex vertex), [List<Vertex>? result]) → List<Vertex>
Collects a connected component via predicate starting at vertex. Returns an empty list if vertex is out of board.
getDistance(Vertex v1, Vertex v2) → int
Manhattan distance between v1 and v2.
getHandicapPlacement(int count, {bool tygem = false}) → List<Vertex>
Returns candidate handicap placements.
getLiberties(Vertex vertex) → List<Vertex>
Returns the unique liberties (adjacent empty points) of the chain at vertex. Returns an empty list for out-of-board or empty vertex.
getNeighbors(Vertex vertex) → List<Vertex>
Returns orthogonal neighbors (up, down, left, right) on the board. Returns an empty list if vertex is out of board.
getRelatedChains(Vertex vertex) → List<Vertex>
Returns all stones of the same color as vertex that are reachable through paths consisting of same-colored stones and empty points. Returns an empty list for out-of-board or empty vertex.
has(Vertex vertex) → bool
Returns whether vertex lies on the board (0 ≤ x < width and 0 ≤ y < height).
hasLiberties(Vertex vertex, [Map<Vertex, bool>? visited]) → bool
Returns whether the chain at vertex has at least one liberty. Returns false for out-of-board or empty vertex.
isEmpty() → bool
isSquare() → bool
isValid() → bool
Returns true if every chain on the board has at least one liberty.
makeMove(Vertex vertex, Stone stone, {bool preventOutOfBoard = false, bool preventSuicide = false, bool preventOverwrite = false, bool preventKo = false}) → Board
Returns a new Board with stone played at vertex.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
parseVertex(String coord) → Vertex?
Parses a Go coordinate string like "D16" to a Vertex. Returns null if invalid or out of board.
set(Vertex vertex, Stone? stone) → Board
Sets stone at vertex. Use null to clear a point.
setCaptures(Stone stone, int value) → Board
Sets the capture count for stone to value. Returns this for chaining.
stringifyVertex(Vertex vertex) → String
Converts vertex to a Go coordinate string like "D16". Returns an empty string if vertex is out of board.
toString() → String
Returns a human-readable textual representation of the board.
override

Operators

operator ==(Object other) → bool
The equality operator.
inherited

Constants

alpha → const String
Column labels used by string conversions (letter I is skipped).