Could use move generation

[dkappe]

For a chess library, it seems the absence of legal move generation is an is an oversight. Hopefully it would be easy to add. It's the only thing keeping this library from being truly useful.

[pioz]

There is a draft: http://blog.pioz.it/chess/classes/Chess/Gnuchess.html

[dkappe]

I meant legal love generation, I.e. A list of all legal moves, not the best move selected by an engine.

DJK

Sent from my iPad

On Mar 17, 2016, at 7:31 AM, Enrico notifications@github.com wrote:

There is a draft: http://blog.pioz.it/chess/classes/Chess/Gnuchess.html

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[pioz]

Ok, I will work on this, but I dont know when -.-

[dkappe]

I can give it a whack, but a hint on how to do it most efficiently would be appreciated.

DJK

On Thu, Mar 17, 2016 at 12:49 PM, Enrico notifications@github.com wrote:

Ok, I will work on this, but I dont know when -.-

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[pioz]

I think that a efficiently way is to use the xray bitboard. For example I want to know all the possible valid move that Qd1 can make: I can get the xray bboard with xray (cur_board, 3, FALSE). Now you can use the method try_move for every pseudo legal move indicated by the xray bboard.

[pioz]

Now you can generate all legal moves for the piece in a square position:

:001 > g = Chess::Game.new
 => #<Chess::Game:0x007f88a529fa88>
:002 > g.board.generate_moves('b1')
 => ["Na3", "Nc3"]

http://pioz.github.io/chess/Chess/Board.html#generate_moves-instance_method