bchess
A chess engine written in modern javascript with a minimal codebase.
Getting Started
Node
npm i bchess
CDN
<script src="https://cdn.jsdelivr.net/npm/bchess@1/dist/bchess.min.js"></script>
Usage
Simply include the library to start using it:
const { Chess, Action, Piece } = require("bchess");
const chess = new Chess({color: "white"});
You can also initialise a new game using FEN notation:
const chess = new Chess({fen:"kb5Q/p7/Pp6/1P6/4p3/4R3/4P1p1/6K1"});
API
move
Carry out the specified move
chess.move({from:"c2",to:"c4"});
A third option is available to specify the piece used for promotion (if available):
chess.move({from:"c2",to:"c4",promote:"Q"});
Returns
One or more Action flags.
The following is a list of possible flags:
- MOVE
- PLAYER_CAPTURE
- OPPONENT_CAPTURE
- CASTLE_KING
- CASTLE_QUEEN
- EN_PASSANT
- PROMOTE
- INVALID_ACTION
set
Set a piece down anywhere on the board:
chess.set({square: "h4", piece: new Piece("Q","white")});
available
Return an array of available moves a piece can make
chess.available({square:"e2"})
history
Get the current game history
chess.history
ascii
Returns an ascii string representing the current board
chess.ascii()
Example output:
+--------------------------+
8 | r n b q k b n r |
7 | p p p p p . p p |
6 | . . . . . P . . |
5 | . . . . . . . . |
4 | . . . . . . . . |
3 | . . . . . N . B |
2 | P P P P P P . P |
1 | R N B Q . R K . |
+--------------------------+
a b c d e f g h
The perspective of the board returned depends on the Chess myColor property.
Options
| Property | Description | Values | Default |
|---|---|---|---|
| border | Toggle border display | true / false | true |
| file | Toggle file display | true / false | true |
| rank | Toggle rank display | true / false | true |
| unicode | Display unicode characters for pieces instead of FEN notation | true/ false | false |
score
Get the current game score
chess.score()
get
Fetch the information at a current square
chess.get({square:"g8"})
fen
Returns the current game state in FEN notation.
chess.fen()
Example output:
rnbqkbnr/ppppp1pp/5P2/1Q6/8/5N1B/PPPPPP1P/RNBQ1RK1
moves
Return the total move count (completed turns)
chess.moves
undo
Undo the most recent move
chess.undo();
turn
Whose turn is it?
chess.turn()
check
Returns pieces in check (and pieces checking them)
chess.check()
checkmate
Returns checkmate status for both sides
chess.checkmate()
stalemate
Returns stalemate status for both sides
chess.stalemate()
moveToSAN
Return the SAN notation of a move
chess.moveToSAN({from:"f2",to:"f4"})