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fairy-stockfish / Fairy-Stockfish

chess variant engine supporting Xiangqi, Shogi, Janggi, Makruk, S-Chess, Crazyhouse, Bughouse, and many more
https://fairy-stockfish.github.io/
GNU General Public License v3.0
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Fair-Stockfish 14 in WinBoard: Illegal move "O-O" (rejected by first chess program) #715

Open numlockkey opened 1 year ago

numlockkey commented 1 year ago

In Winboard pick New Variant ... CRC

Psste this position: br2q1kr1n/ppp3pppp/4pp3c/1n1p6/1Q3P4/1P1P4P1/PBP1P1PPCb/1RNB2KR1N b HBhb - 1 1

Set Fairy-Stockfish 14 to play White.

Try to castle manually by first clicking the King, and then the Rook.

I get this error:

Illegal move "O-O" (rejected by first chess program)

The same move tested in Cute Chess works fine.

ianfab commented 1 year ago

Yes, Fairy-SF currently only understands the normal castling notation in the CECP/xboard protocol, not the FRC notation. The CECP documentation states that

Castlings are indicated as the King move, e.g. e1g1 or e8c8, except for Fischer castling, which is O-O or O-O-O (oh, not zero!).

In UCI that all works fine, therefore other GUIs have no issue.