Houdini (chess)
Developer(s) | Robert Houdart |
---|---|
Initial release | May 15, 2010 |
Stable release | 6.03
/ November 20, 2017 |
Operating system | Microsoft Windows |
Type | Chess engine |
License | Proprietary |
Website | www |
Houdini is a UCI chess engine developed by Belgian programmer Robert Houdart. It is influenced by open-source engines IPPOLIT/RobboLito, Stockfish, and Crafty. Versions up to 1.5a are available for non-commercial use, while 2.0 and later are commercial only. Houdini 6 used to be one of the highest-rated engines on major chess engine rating lists, but has since fallen behind significantly due to a lack of updates.[1]
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Playing style[]
Chess commentator and video annotator CM Tryfon Gavriel compared Houdini's playing style to that of the Romantic Era of chess, where an attacking, sacrificial style was predominant.[2] According to Robert Houdart, Houdini's advantage against other top engines is in its handling of piece mobility, which is why it "favors aggressive play that tries to win the game".[3]
Version history[]
Version | Release date | Features[4] |
---|---|---|
1.0 | May 15, 2010 | First release |
1.01 | June 1, 2010 | Bug fixes, improved search algorithm |
1.02 | June 18, 2010 | SMP and hash collision bug fixes. Work-around for Shredder GUI. |
1.03 | July 15, 2010 | Multi-PV, searchmove and large page support. Improved evaluation function. |
1.03a | July 17, 2010 | Bug fix for Multi-PV |
1.5 | December 15, 2010 | Improved search and evaluation. Gaviota Table Base Support. |
1.5a | January 15, 2011 | Maintenance update with work-arounds for Fritz GUI and other minor improvements. |
2.0 | September 1, 2011 | First commercial release. Improved analysis capabilities, enhanced search and evaluation. Houdini Pro version for high-end users with powerful hardware (multi-core support). Chess960 support. Strength limit feature. Position learning. Save hash to file, load hash from file, never clear hash. |
2.0b | November 7, 2011 | Maintenance update with minor bug corrections and Nalimov EGTB support. |
2.0c | November 20, 2011 | Maintenance update with minor bug corrections and new analysis options. MultiPV_cp option to limit multi-PV analysis to moves within a range of the best move. FiftyMoveDistance option to make the 50-move rule kick in earlier. UCI_Elo and UCI_LimitStrength options as UCI standard-compliant alternative to Strength option. Exit on detection with GUI exit. |
3.0 | October 15, 2012 | Major new version. Improved search and evaluation (+50 Elo), Tactical Mode, Scorpio bitbases, accelerated Principal Variation Search "Smart Fail-High", optimized hash usage. |
4.0 |
November 25, 2013 |
Major new version. Improved search and evaluation (+50 Elo), 6-men Syzygy table bases (coding provided by Ronald de Man) |
5.0 |
November 7, 2016 |
Major new version, about 200 Elo stronger. Rewritten evaluation function, deeper search. |
5.01 |
November 15, 2016 |
Maintenance update with some interface corrections and improvements. |
6.0 |
September 15, 2017 |
Major new version. Improved search and evaluation (+50-60 Elo), enhanced multi-threading. |
6.01 |
September 24, 2017 |
Maintenance update with Nalimov EGTB correction and new output option. |
6.02 |
October 1, 2017 |
Maintenance update with Polyglot book support. |
6.03 |
November 20, 2017 |
Correction for incorrect detection of stalemate in positions with white pawn capture moves. |
The latest stable release of Houdini comes in two versions: Houdini 6 Standard and Houdini 6 Pro. Houdini 6 Pro supports up to 128 processor cores, 128 GB of RAM (hash) and is NUMA-aware, Houdini 5 Standard only supports up to 8 processor cores, 4 GB of hash and is not NUMA-aware. As with many other UCI engines, Houdini comes with no GUI, so a chess GUI is needed for running the engine. Houdini 5 uses calibrated evaluations in which engine scores correlate directly with the win expectancy in the position.[4]
Competition results[]
Houdini used to be one of the most successful engines in TCEC, with three championship wins to date,[5][6] but since season 18 it no longer participates in TCEC due to it allegedly containing plagiarized code (see Controversy).
Controversy[]
Houdini 6 has been alleged to be a Stockfish 8 derivative without providing the sources on request, and thus, violating the GPL license. This has resulted in TCEC revoking Houdini's championship results, and disallowing Houdini from competing.[7][8][9] Leaked source code has seemingly been shown to produce almost identical play to Houdini 6, while containing direct references to Stockfish in the code documentation.
Houdini 6 is also no longer available on chessbase.com due to it being a Stockfish derivative.
Notable games[]
Rybka - Houdini
a | b | c | d | e | f | g | h | ||
8 | ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() | 8 | |||||||
7 | 7 | ||||||||
6 | 6 | ||||||||
5 | 5 | ||||||||
4 | 4 | ||||||||
3 | 3 | ||||||||
2 | 2 | ||||||||
1 | 1 | ||||||||
a | b | c | d | e | f | g | h |
- TCEC Houdini - Rybka Match 2011 · Sicilian Defense: Alapin Variation. Stoltz Attack Ivanchuk Line (B22) · 0–1 Houdini sacrifices three pawns for piece activity and defeats the reigning computer chess champion Rybka in this game, popularly dubbed as the "Houdini Immortal".[10][11]
- TCEC Houdini - Rybka Match 2011 · Spanish Game: Closed Variations (C84) · 0–1[12]
- TCEC Houdini - Rybka Match 2011 · Queen Pawn Game: London System (D02) · 1–0 Houdini plays a pawn sacrifice on move 43.[13]
References[]
- ^ "CCRL 40/40". Retrieved 12 December 2021.
- ^ "Houdini with Black pieces in the Thoresen Chess Engines Competition. Game shows Houdini playing style from 6:23" on YouTube
- ^ "Interview with Robert Houdart, Mark Lefler and GM Larry Kaufman". chessdom.com. November 23, 2017. Retrieved November 24, 2017.
- ^ a b Cruxis, Retrieved 16 June 2012
- ^ "Houdini is TCEC Season 10 champion!". 7 December 2017.
- ^ "TCEC Season 18 Engines". 25 May 2020.
- ^ "Open Source Community Critical Of Chessbase, Fat Fritz 2". chess.com. 25 February 2021.
- ^ "ChessBase's Fat Fritz 2 condemned as 'rip-off' Stockfish clone". chess24. 22 February 2021.
- ^ "Engines and authors - TCEC wiki".
- ^ Video annotation by Kingscrusher on YouTube
- ^ Monokroussos, Dennis. "Houdini 1.5a defeats Rybka 4: 23.5-16.5". Retrieved 25 October 2013.
- ^ Video annotation by Kingscrusher on YouTube
- ^ "Free Houdini beats commercial Rybka 23.5-16.5". Chessvibes. 10 February 2010. Retrieved 25 October 2013.
External links[]
- Official website
- Interview with Houdart about the genesis and strengths of his program
- Chess engines
- 2010 software