Critter
[ Agropelter, a fearsome critter [1] Critter,
an UCI compliant chess engine by Richard Vida, executables freely available for personal use to run under Windows, Linux, Android and Mac OS [2] . Starting in late 2008, Critter was first written in Object Pascal compiled with Delphi, now available as open source engine [3] [4], and was ported to C / C++ in 2009 [5] . It consistently evolved through various board representations from 0x88 to bitboards, as acknowledged by Richard Vida, also incorporating ideas from strong open source programs like Ippolit [6] , to a world class engine which achieved top five of most engine rating lists [7]. In 2012, Critter had its over the board debut at the ICT 2012, where it became strong runner-up behind the Rybka cluster.
Description
Critter applies a principal variation search with aspiration windows, null move pruning [8] and other state of the art forward pruning, reduction and extension techniques, such as the Botvinnik-Markoff extensions [9] . It can search in parallel with up to eight threads [10] , supports Gaviota tablebases [11] , and is able to play Chess960 [12] . Critter features a tapered eval with a score pair class and overloaded operators [13] [14] , and blockage detection in late endgames [15] .
Selected Games
ICT 2012, round 7, Rybka - Critter [16] [17]
Publications
- Arno Nickel (2012). Die schöne neue Welt der Schachengines. SCHACH 2,3,5,6 2012, pdf (German) [18]
Forum Posts
2009
- Critter 0.34 : 2146 by Patrick Buchmann, CCC, April 18, 2009
- Critter 0.38 : 2330 by Patrick Buchmann, CCC, May 22, 2009
- Critter 0.40 released by Richard Vida, CCC, July 26, 2009
- Critter 0.40 : 2471 by Patrick Buchmann, CCC, August 01, 2009
- Critter: Pascal vs C by Richard Vida, CCC, August 27, 2009 » C, Pascal
- Critter 0.42 available by Richard Vida, CCC, October 08, 2009 » Pascal
- Critter 0.42 : 2649 by Patrick Buchmann, CCC, October 11, 2009
2010 …
- Critter 0.52 available by Richard Vida, CCC, Jan 25, 2010 » C
- Critter 0.52b added to the IPON list … by Ingo Bauer, CCC, February 04, 2010
- Strange knight underpromotion by Critter by Richard Vida, CCC, March 04, 2010
- Critter goes SMP (version 0.60 is released) by Richard Vida, CCC, April 13, 2010
- Critter 0.60: 2718 by Patrick Buchmann, CCC, April 14, 2010
- Critter 0.70 is out by Richard Vida, CCC, May 23, 2010
- Critter 0.80 by Richard Vida, CCC, July 24, 2010
- Critter 0.90 released by Richard Vida, CCC, November 29, 2010
- Critter - looking at static evaluation by Richard Vida, CCC, December 11, 2010
2011
- Critter 1.0 available by Richard Vida, CCC, March 16, 2011
- Critter 1.0 for Linux by Richard Vida, CCC, March 22, 2011 » Linux
- My experience with Linux/GCC by Richard Vida, CCC, March 23, 2011
- Critter bugfix update by Richard Vida, CCC, March 28, 2011 [19]
- Critter 1.2 update + new homepage by Richard Vida, CCC, June 25, 2011 » Android
- Critter 1.2 SEEMS to be a member of the Ippo family by Kai Laskos, CCC, July 02, 2011
- for Pascal fans: Critter by Richard Vida, CCC, September 16, 2011
2012 …
- Re: World Computer Chess Championship ? by Richard Vida, CCC, June 11, 2012
- Re: Critter 1.6 released! by Richard Vida, CCC, June 15, 2012
- Continuation of Critter would be very appreciated by Mike Scheidl, CCC, May 15, 2013
2020 …
- OpenCritter compiled for Linux with Free Pascal by Roland Chastain, CCC, November 17, 2020
External Links
Chess Engine
- Critter (chess) from Wikipedia
- Critter for win32/64, linux and android platforms hosted by Emil Vlasák
- SourceForge.net: Critter Chess - Project Web Hosting - Open Source Software (Pascal Version)
- GitHub - rchastain/open-critter: UCI chess engine written in Pascal by Richard Vida hosted by Roland Chastain [20]
- Critter at CCRL 40/15
Misc
- Critter (disambiguation page) from Wikipedia
- Critters (block cellular automaton) from Wikipedia
- Little Critter from Wikipedia
- “The Critter” (Chinese pangolin) from Wikipedia
- Fearsome critters from Wikipedia
- Critters (film series) from Wikipedia
- Critters (comics) from Wikipedia
References
- ↑ Agropelter from Henry H. Tryon (1939). Fearsome Critters. Illustrated by Margaret R. Tryon, Idlewild Press, Cornwall, NY, Wikimedia Commons
- ↑ Critter for win32/64, linux and android platforms hosted by Emil Vlasák, Mac OS version compiled by Jeremy Bernstein
- ↑ for Pascal fans: Critter by Richard Vida, CCC, September 16, 2011
- ↑ SourceForge.net: Critter Chess - Project Web Hosting - Open Source Software
- ↑ Critter: Pascal vs C by Richard Vida, CCC, August 27, 2009
- ↑ Re: World Computer Chess Championship ? by Richard Vida, CCC, June 11, 2012
- ↑ Critter (chess) from Wikipedia
- ↑ Interview with Richard Vida by Frank Quisinsky, February 20, 2010
- ↑ Re: World Computer Chess Championship ? by Richard Vida, CCC, June 11, 2012
- ↑ Critter goes SMP (version 0.60 is released) by Richard Vida, CCC, April 13, 2010
- ↑ Critter 0.70 is out by Richard Vida, CCC, May 23, 2010
- ↑ Critter 0.80 by Richard Vida, CCC, July 24, 2010
- ↑ Re: talk about IPP’s evaluation by Richard Vida, CCC, November 07, 2009 » Ippolit, SIMD and SWAR Techniques
- ↑ My experience with Linux/GCC by Richard Vida, CCC, March 23, 2011
- ↑ Chiron 1.1 bug? by Richard Vida, CCC, December 24, 2011
- ↑ Leiden Round 7: Rybka vs Critter by Ray, Rybka Forum, May 13, 2012
- ↑ ICT 12 - PGN download, CSVN
- ↑ Part 1 covers Houdini, Rybka, Komodo, Stockfish, Critter, Naum, Chiron and Spike
- ↑ Difficult position to Critter by Jouni Uski, CCC, March 24, 2011
- ↑ OpenCritter compiled for Linux with Free Pascal by Roland Chastain, CCC, November 17, 2020