RedQueen is a free and open source chess program available for Windows and Linux. The code has been written in C++ using minimal library dependencies as possible, so that it could be easily ported to other OS. RedQueen is an UCI chess engine which means that you will need to have installed on your computer a chess graphic interface such as Arena or XBoard/Winboard to be able to play with it. The name RedQueen comes from the Red Queen character in Lewis Carroll's Through the Looking-Glass novel.

Please follow the instructions of your favorite GUI (Arena, Winboard/Xboard, Scid, Chessbase, etc) to install the engine on it.

RedQueen can be executed from the command line of your Operating System. The command:

redqueen bench

will run a benchmark using a pre-defined set of chess positions.

Running RedQueen without arguments will make it enter in the UCI mode. You can query the UCI specification to learn about the available commands:

http://www.shredderchess.com/chess-info/features/uci-universal-chess-interface.html

RedQueen have a special command not specified in the UCI documentation. In the UCI mode you can type the command 'test eval' which will display a detailed information on the evaluation of the current chess position. Example.:

position fen 1Q6/5kpp/2p4r/b4p2/P2R4/1N4P1/5PKP/4q3 b - - 0 1
test eval
Material[WHITE]:          2735
Material[BLACK]:          2740
Pieces(PST&Other)[WHITE]: -21
Pieces(PST&Other)[BLACK]: -39
Pawns[WHITE]:             11
Pawns[BLACK]:             6
Mobility&Space[WHITE]:    47
Mobility&Space[BLACK]:    35
Pieces threats[WHITE]:    7
Pieces threats[BLACK]:    0
King threats[WHITE]:      1
King threats[BLACK]:      23
Endgame score(WHITE):    89
Endgame score(BLACK):    28
Middlegame score(WHITE): 24
Middlegame score(BLACK): 28
Main eval:                +15

RedQueen was completely written from the scratch. Although it has taken many ideas from many open source projects.

The following open source projects had directly influenced the development of RedQueen:

Stockfish Sloppy Sungorus Robbolito Crafty Gull

RedQueen uses the magic move bitboard generation by Pradyumna Kannan.

RedQueen uses the mersenne twister PRNG by Takuji Nishimura and Makoto Matsumoto

The rating lists/testers bellow do an amazing job by testing and reporting bugs of RedQueen:

http://www.husvankempen.de/nunn/ http://computerchess.org.uk/ccrl/ http://www.tcec-chess.org/

Aart Bik did a very nice compile of RedQueen for the Android platform.

Thanks everyone! :)

RedQueen is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

RedQueen is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with RedQueen.  If not, see <http://www.gnu.org/licenses/>.

If you find RedQueen useful, you can help in the following ways:

• Testing & reporting bugs
• Expert advise (specific chess knowledge)

If you have any suggestions/doubts drop me an e-mail:

bhlangonijr at google dot com

Regards, Ben-Hur Carlos Vieira Langoni Junior