Changes

an [[UCI]] compliant [[:Category:Open Source|open source engine]] in the [https://en.wikipedia.org/wiki/Public_domain public domain] by [[Vadim DemichevThinkingALot]] <ref>[https://en.wikipedia.org/wiki/Chess_engine Chess engine from Wikiepdia]</ref>, inspired by ideas and code from other open source engines, notably from [[IvanHoe]] of the [[Ippolit]] family of programs, and from [[Strelka]], whose authors are suspected of [https://en.wikipedia.org/wiki/Reverse_engineering reverse engineering] [[Rybka]], to examine and use her ideas. [[Ron Murawski|Ron Murawski's]] Computer-Chess Wiki mentions GullChess as IvanHoe derivative <ref>[http://computer-chess.org/doku.php?id=computer_chess:wiki:lists:chess_engine_list Chess Engine List] from [[Ron Murawski|Ron Murawski's]] [http://computer-chess.org/doku.php?id=home Computer-Chess Wiki]</ref>. The further socialization of concrete implementations with disputed origin in the public domain, as already started with Ippolit, remains a highly controversial topic.

Gull '''2.1''', released in June 2013, has [[Evaluation|evaluation]] weights optimized with the use of [[Automated Tuning|automated tuning]] (source code included). Gull's 2.1 evaluation is no longer almost identical to that of IvanHoe. Further, it features some minor search, [[Time Management|time management]] and [[Parallel Search|SMP]] efficiency enhancements <ref>[http://www.open-chess.org/viewtopic.php?f=7&t=109&start=120#p18910 Re: gull chess] by [[Vadim Demichev|ThinkingALot]], [[Computer Chess Forums|OpenChess Forum]], June 17, 2013 (Gull 2.1)</ref>.

Gull '''3''', released April 17, 2014, with further [[Automated Tuning|optimization]] of evaluation weights and a rewritten [[Parallel Search|SMP search]], features nonlinear [[King Safety#PawnShield|king shelter evaluation]] and more [[Endgame|endgame knowledge]]. [[Basil Falcinelli]] implemented a [[Linux]] port <ref>[http://www.talkchess.com/forum/viewtopic.php?t=58071 Gull 3 (Linux port) released] by [[Basil Falcinelli]], [[CCC]], October 28, 2015</ref> and [[Syzygy Bases]] support, introducing [[Syzygy Bases#Fathom|Fathom]] <ref>[http://www.talkchess.com/forum/viewtopic.php?t=58299 Gull 3 Linux+Syzygy and Fathom released] by [[Basil Falcinelli]], [[CCC]], November 20, 2015</ref>, while [[Michael Byrne]] worked on a [[Mac OS]] port <ref>[http://www.talkchess.com/forum/viewtopic.php?t=58096 Gull 3 x64 Mac Results] by [[Michael Byrne|Michael B]], [[CCC]], October 30, 2015</ref> dubbed <span id="Hawkeye"></span>'''Hawkeye''' <ref>[http://www.talkchess.com/forum/viewtopic.php?t=60695 Hawkeye 1.01] by [[Michael Byrne|Michael B]], [[CCC]], July 05, 2016</ref>, [[Tom Hyer]] introduced his Gull 3 derivative <span id="Roc"></span>'''Roc''' <ref>[https://github.com/TomHyer/[Roc GitHub - TomHyer/Roc: C++ chess engine derived from Gull 3]</ref>], and [[Norman Schmidt]] <span id="SeaGull"></span>'''SeaGull''' also based on Gull 3 <ref>[https://github.com/FireFather/seagull GitHub - FireFather/seagull: chess engine based on Gull 3] by [[Norman Schmidt]]</ref>.

* [http://immortalchess.net/forum/showthread.php?t=2354 Проект "Чайка"] by [[Vadim Demichev|ThinkingALot]], [[Computer Chess Forums|immortalchess]], June 07, 2010, [http://translate.google.com/translate?sl=ru&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&layout=2&eotf=1&u=http%3A%2F%2Fimmortalchess.net%2Fforum%2Findex.php translated] by [https://en.wikipedia.org/wiki/Google_Translate Google Translate]

: [http://www.open-chess.org/viewtopic.php?f=7&t=109&p=724#p724 Re: gull chess] by [[Vadim Demichev|ThinkingALot]], [[Computer Chess Forums|OpenChess Forum]], June 13, 2010 » [[Gaviota]]: [http://www.open-chess.org/viewtopic.php?f=7&t=109&start=120#p18910 Re: gull chess] by [[Vadim Demichev|ThinkingALot]], [[Computer Chess Forums|OpenChess Forum]], June 17, 2013 (Gull 2.1): [http://www.open-chess.org/viewtopic.php?f=7&t=109&start=150#p20221 Re: gull chess] by [[Vadim Demichev|ThinkingALot]], [[Computer Chess Forums|OpenChess Forum]], January 26, 2014 (Gull 2.8 beta & Gull 2.9 alpha)

* [http://www.open-chess.org/viewtopic.php?f=5&t=2378 DTS-like SMP] by [[Vadim Demichev|ThinkingALot]], [[Computer Chess Forums|OpenChess Forum]], July 25, 2013 » [[Parallel Search]]* [http://immortalchess.net/forum/showpost.php?p=464718&postcount=326 Re: Gull] by [[Vadim Demichev|ThinkingALot]], [[Computer Chess Forums|immortalchess]], February 10, 2014

* [http://gullchess.sourceforge.net/ SourceForge.net: GullChess - Project Web Hosting - Open Source Software] by [[Vadim Demichev|ThinkingALot]]

* [https://bitbucket.org/hyer/sonsofthebird/src/052b62b0c78d11889379d5909bbe617b70274076/Slizzard/?at=default hyer / SonsOfTheBird / source / Slizzard — Bitbucket] by [[Tom Hyer]] <ref> [http://www.talkchess.com/forum/viewtopic.php?t=61195 Future of Gull] by [[Tom Hyer]], [[CCC]], August 23, 2016</ref>* [https://github.com/TomHyer/Roc GitHub - TomHyer/Roc: C++ chess engine derived from Gull 3] by [[Tom Hyer]] » [[Roc]]

* [http://www.computerchess.org.uk/ccrl/4040/cgi/engine_details.cgi?print=Details&each_game=1&eng=Gull%201.2%2064-bit#Gull_1_2_64-bit Gull 1.2 64-bit] in [[CCRL|CCRL 40/4015]]* [http://www.computerchess.org.uk/ccrl/4040/cgi/engine_details.cgi?match_length=30&each_game=1&print=Details&each_game=1&eng=Gull%203%2064-bit%204CPU#Gull_3_64-bit_4CPU Gull 3 64-bit 4CPU] in [[CCRL|CCRL 40/4015]]