Fortress (Engine)

**[[Home]] * [[Engines]] * Fortress**
|| [[image:Buhen3.jpg link="http://en.wikipedia.org/wiki/File:Buhen3.jpg"]] ||~ || **Fortress**,
a [[Chess Engine Communication Protocol]] compliant chess engine written by [[Alessandro Damiani]] in [[C]], first released in October 1998 <ref>[[http://wbec-ridderkerk.nl/html/details1/Fortress.html|Fortress]] from [[WBEC|WBEC Ridderkerk]]</ref>. Fortress pioneered in [[Rotated Indices]], a deconcentrated version of [[Rotated Bitboards|rotated bitboards]]. Alessandro once mentioned improving a version of [[Günther Schrüfer|Schrüfer's]] "most selective" [[Quiescence Search|quiescence search]] <ref>[[http://groups.google.com/group/rec.games.chess.computer/browse_frm/thread/375e65821715995f|futility cut-offs]] by [[Alessandro Damiani]], [[Computer Chess Forums|rgcc]], November 14, 1997</ref>, found in Schrüfer's Ph.D. thesis //Minimax-Suchen// <ref>[[Günther Schrüfer]] (**1988**). //Minimax-Suchen : Kosten, Qualität und Algorithmen//. [[http://en.wikipedia.org/wiki/Technical_University_of_Braunschweig|TU Braunschweig]] (German)</ref>. ||
|| Buhen fortress <ref>Artists impression of the battlements at [[http://en.wikipedia.org/wiki/Buhen|Buhen fortress]] in [[http://en.wikipedia.org/wiki/Ancient_Egypt|Ancient Egypt]] about 1800 BC, Source: [[http://www.safran.be/products.php?cat=385|Franck Monnier]] (**2010**). //[[http://www.safran.be/proddetail.php?prod=CEA11|Les forteresses égyptiennes. Du Prédynastique au Nouvel Empire, collection Connaissance de l'Égypte ancienne]]//. Safran (éditions), Bruxelles, 978-2-87457-033-9, [[http://en.wikipedia.org/wiki/Fortification|Fortification from Wikipedia]]</ref>  ||~ ||^ ||
[[toc]]
=Technical Details=
<ref>based on [[http://www.rwbc-chess.de/download.htm|Downloads]] from [[RWBC]] by [[Günther Simon]], Fortress 1.62.zip / readme.doc</ref>
* Based on [[Bitboards|bitboards]] ([[Rotated Indices|not the same]] [[Rotated Bitboards|rotated bitboards]] as in [[Crafty]])
* [[Search|Search algorithm]] is [[Fail-Soft]] [[Alpha-Beta]]
* [[Iterative Deepening]]
* Iterative [[Aspiration Windows|Aspiration Window]]
* [[Null Move Pruning]]
* [[Extensions|Search extensions]] ([[Check Extensions|checks]], [[Passed Pawn Extensions|promotion threats]], [[Mate Threat Extensions|piece threats]])
* [[Transposition Table|Transposition table]]
* [[Killer Heuristic]]
* [[History Heuristic]]
* [[Evaluation|Static evaluation]]: important information is [[Incremental Updates|calculated incrementally]] (e.g. [[Passed Pawn|passed pawns]]).

=See also=
* [[Fortress]] (Chess term)
* [[Gk]]
* [[Rotated Indices]]
* [[Stonewall]]
* [[Ziggurat]]

=Forum Posts=
* [[http://groups.google.com/group/rec.games.chess.computer/browse_frm/thread/375e65821715995f|futility cut-offs]] by [[Alessandro Damiani]], [[Computer Chess Forums|rgcc]], November 14, 1997 
* [[http://www.stmintz.com/ccc/index.php?id=39509|New Version: FORTRESS V1.5, the new Morphy?]] by [[Alessandro Damiani]], [[CCC]], January 15, 1999
* [[http://www.stmintz.com/ccc/index.php?id=67954|Re: Home page for Fortress! ToDo: Opening book, ...]] by [[Alessandro Damiani]], [[CCC]], September 09, 1999
* [[http://www.open-aurec.com/wbforum/viewtopic.php?f=18&t=30206&p=115019|Fortress 1.62 is available !]] by [[Frank Quisinsky]], [[Computer Chess Forums|Winboard Forum]], May 22, 2000
* [[http://www.open-aurec.com/wbforum/viewtopic.php?f=18&t=37189&p=141153|Fortress 1.62 and Draw by 50 moves rule ?]] by [[Brice Boissel]], [[Computer Chess Forums|Winboard Forum]], May 08, 2002

=External Links=
==Chess Engine==
* [[http://wbec-ridderkerk.nl/html/details1/Fortress.html|Fortress]] from [[WBEC|WBEC Ridderkerk]]
* [[http://www.g-sei.org/fortress/|Fortress « G 6]]
* [[http://www.rwbc-chess.de/download.htm|Downloads]] from [[RWBC]] by [[Günther Simon]]
==Chess==
* [[http://en.wikipedia.org/wiki/Fortress_%28chess%29|Fortress (chess) from Wikipedia]]
* [[http://en.wikipedia.org/wiki/Fortress_chess|Fortress chess (Variant) from Wikipedia]]
==Misc==
* [[http://en.wikipedia.org/wiki/Fortress_%28programming_language%29|Fortress (programming language) - Wikipedia]]
* [[http://en.wikipedia.org/wiki/Fortification|Fortification from Wikipedia]]
* [[http://en.wikipedia.org/wiki/Fort_%28disambiguation%29|Fort (disambiguation) from Wikipedia]]

=References= 
<references />
=What links here?= 
[[include page="Fortress (Engine)" component="backlinks" limit="20" ]]
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