Gromit

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GromitChess, (Gromit) a chess engine by Frank Schneider and Kai Skibbe. Gromit, later renamed to GromitChess, was initially written by Frank. In 1999 former tester Kai Skibbe joined the development. Gromit and GromitChess played several IPCCCs, the WMCCC 1995, WCCC 1999 in Paderborn and the WMCCC 2001 in Maastricht, where it won the title of the Amateur World Microcomputer Chess Champion. Early versions (1.2) were standalone engines with an own GUI, later versions (> 2.0) were WinBoard/XBoard compatible, a dedicated version (3.1) was available as Young Talent by ChessBase running under the Fritz6 GUI. GromitChess (3.10.3) was incorporated into the PocketGrandmaster for Pocket PC, and became predecessor of Anaconda.

=Description= given in 1999 from the ICGA tournament site : GromitChess is a C++-program, developed in a Linux-environment (Emacs, gcc). It searches about 25000 to 50000 nodes per second on a K6/200 and tries to be intelligent rather than fast. Attacktables are the primary datastructure (16 bit for every square and player; bit n is set if piece n attacks the square). The search uses iterative deepening, PVS, transposition tables, killer- and history heuristic, nullmove (R=2), about 10 chess-specific extensions and some pruning heuristics. The quiescence uses a static exchange evaluator and includes some checks and other threatening moves. Parts of the evaluation are initialized at the root but most of the work is done at the leafnodes. You can find more information and executables in the WWW.

=Copy Make= Frank Schneider on Gromit's Copy-Make approach : I think it depends on your program and the board representation. Gromit uses copy+update and >1KB is copied every move (which is maybe too much). When I decided to do it that way (on an Amiga) I only considered clock cycles, but on a PC the low memory-bandwidth is the real problem. Since Gromit's evaluation and search heuristics use most of the processor time I never tried update+take back, because I guess it would give me less than 10% speedup, probably being slower than copy+update.

There are some advantages of copy+update: - it is easy to program - it is easier to do some 'clever' things that would be difficult to take back - you can compare the current position with previous positions in the search tree An alternative would use a mix of copied and static data structures.

=See also=
 * Anaconda
 * PocketGrandmaster

=Forum Posts=

1997 ...

 * Where I can get Gromit Chess? by Torsten Schoop, rgcc, February 07, 1997
 * GromitChess homepage by Frank Schneider, CCC, February 22, 1998
 * New: xboard-Version of GromitChess by Frank Schneider, CCC, October 05, 1998
 * GromitChess [Home Page update] by Frank Schneider, CCC, December 04, 1998
 * GromitChess for download by Frank Schneider, CCC, December 06, 1998
 * New version of GromitChess by Frank Schneider, CCC, January 03, 1999
 * Re: Unmake move v copy the board by Frank Schneider, CCC, January 24, 1999
 * New version of GromitChess by Frank Schneider, CCC, March 22, 1999
 * GromitChess 2.13 by Frank Schneider, CCC, March 24, 1999
 * New: Gromit 2.20 by Frank Schneider, CCC, June 20, 1999 » WCCC 1999

2000 ...

 * Gromitchess bookcheating (for Vincent DIEPEVEEN) by Gian-Carlo Pascutto, CCC, August 23, 2001
 * Goliath Light, Gromit, Patzer, SOS, etc. commercially sold by Theo van der Storm, CCC, August 28, 2001
 * The Crazy Bishop 0046 and Gromit 3.8.2 by Federico Corigliano, CCC, August 31, 2001 » The Crazy Bishop
 * Anyone using the Gromit engine? by Jonathan Parle, CCC, January 12, 2002
 * Re: Gromit 3.8.2 (wb) released! by Frank Schneider, CCC, January 14, 2002
 * Re: Is Gromit 3.9.5 is out? by Frank Schneider, CCC, July 14, 2002
 * Anaconda 1.0 (ex-GromitChess) available as CB-native by Kai Skibbe, CCC, March 08, 2003
 * Gromit 1.2 by Philippe, CCC, January 12, 2008

2010 ...

 * ChessBase native engines (freeware) by Norbert Raimund Leisner, CCC, March 13, 2014

=External Links=

Chess Engine

 * GromitChess' ICGA Tournaments
 * Index of /chess/engines/Norbert's collection/GromitChess (Compilation) by Norbert Raimund Leisner, hosted by Kirill Kryukov
 * New features in GromitChess 1.2

Misc

 * Wallace & Gromit - The Official Site
 * Wallace & Gromit from Wikipedia

=References= Up one level