stonkfish

Source Code

Model

File	Description
cell.py	Chess board square (FEN: a1, b2, f8...)
chess.py	Chess game model
fen.py	Parsing FEN strings into objects
game.py	Base game model
move.py	Chess move (FEN: a1a2, b1b8, ...)
piece.py	Chess piece (FEN: p, n, b, r, k, q)
result.py	Chess game result
state.py	Chess game state (FEN: rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR w KQkq - 0 1)
vector.py	Support direction abstraction (up, down, left, right...)

Algorithm

File	Description
evaluation.py	Evaluation functions
player.py	Players (random, alpha-beta 1-10)
strategy.py	Search algorithm (alpha-beta cutoff)

Examples

Overall

• The type of the board:

state.board: list[list[Piece]]

See piece.py for piece format.

• Use state.at() to get a piece at a Cell:

piece = state.at(Cell(7, 0)) # get piece at square a1

# or use FEN
piece = state.at(parseCell("a1"))

• Empty cells are stored as Piece(PieceType.NONE). You can check for empty cells using:

piece = state.at(parseCell("a2"))
state.is_empty_cell(piece) # True

• You can use state.to_move to get the turn (it is PieceColor.WHITE or PieceColor.BLACK)

Get all legal moves

state = State()
legal_moves = state.possible_moves()

Chess move

WARNING: state.move() does not check for legal moves, you must use one of the moves from state.possible_moves()

from src.state import State

# P1 moves pawn from e2 -> e4
# you can also use: move = parseMove("e2e4")
move = Move(Cell(6, 4), Cell(4, 4))

if move in legal_moves:
    state = state.move(move) # returns new state

Check game status

# check if game is over
if state.game_over():
    print(state.result) # check result.py for format
else:
    print("Game is not over yet")