by José Carlos Martínez Galán
Averno is designed to run under Winboard. It supports protocols 1 and 2, but it's optimized for protocol 2.
Averno035.zip includes two files:
Averno035.exe
Averno035.per
Averno035.per is a personality file. It's meant to contain configuration information. I recommend to copy it to a new file (let's call it MyPersonality.per) and modify it. Averno will use the default settings for every parameter not found in the configuration file, so you actually only need to include those you want to modify.
I'll write a more detailed explanation on the personality file parameters soon, but for now I'll name the most important ones:
TABLA_HASH n : Sets the has table size to a maximum of n Megs. The actual amount of allocated memory will be smaller than that because Averno uses certain fixed (3, 6, 12...).
NALIMOV_PATH path : You can indicate Averno to use Nalimov's endgame tablebases. Set here the path to them.
EGTB_CACHE_SIZE n : Use this parameter to indicate the number of Megs to use as EGTB cache.
VENT_ASP n : Use this parameter to indicate the size of the aspiration window (in centipawns). The impact of this parameter in Averno's play could be summarized: in quiet positions, the smaller n is, the deeper Averno will search. In complex positions, a small n will cause Averno to research a lot of times and thus, search less deep. Typical values are between 25 and 50. Note: actually the size of the AP will be 2n, because Averno adds n and substracts n to the previous search score.
UMBRAL_FINAL n : The total material (in centipawns) Averno will consider the limit between MidGame and EndGame.
REDUCCION_NULL n : n = 0 disables null-move. Otherwise, Averno will use null move with a factor R = n/2. This means that, for swallow depths, Averno always uses reduction factor of two, but for deep depths it will use n. Typical values for this parameter are 2 and 3.
JAQUES_QSEARCH n : n = 1 will enable "out-of-check extension" in qsearch. This means that, if white captures with check, black is forced to search every move that leaves the check. Use n = 0 to disable it (default option). This "extension" makes the program can find mates and threats involving checks sooner, but will cause the program to search less deep in average.
EXT_RECAP n : Again n = 0 to disable and n = 1 to enable. Recapture extension means that every two consecutive captures that leaves material as it was before them will be extended. Recapture extension is meant to partially avoid horizont effect.
EXT_PEON_7 n : Again n = 0 to disable and n = 1 to enable. If enabled, every time a pawn reaches seventh rank Averno will extend 1 ply to see if it is really a threat.
LAZY n : Lazy margin. This is a number that Averno will use to avoid complicated evaluation if it believes the position is clear enough. n = 200 means that if after the simplest eval the score difference is more than 2 pawns above beta or below alpha, the position is not interesting.
FUTILITY n : This number is used to prune some bad moves near the tips. Both LAZY and FUTILITY, big numbers will make Averno search deeper, but at the cost of the risk of missing important information.
EXTENSION_NULL n : n = 0 to disable and n = 1 to enable. If enabled, every time Averno finds a big threat during the null-move-search, it will extend to see if the threat is real.
IID n : Again n = 0 to disable and n = 1 to enable. Internal Iterative Deepening. AFAIK, invented by Bob Hyatt. This is an internal reduced search that is performed when no hash move is found. IMO, it works fine in Averno, but other programmers have reported no benefit.
ICS n : Again n = 0 to disable and n = 1 to enable. This parameter is used to kibitz information in chess servers. In this version, there's no kibitz file (it's hard coded) so if enabled, Averno will only kibitz against "known" opponents: Hossa, Tinker, Postmodernist, Sjeng... In future versions, there will be a kibitz file where you can chose the opponents to kibitz.
LIBROB_FICH path : In this version, different personalities can use different books. Use this parameter to tell Averno what file must be used as white book. If ommited, Averno will still use AvernoB.libro. Note that if the files are in the same directory as the program, the full path is not needed.
LIBRON_FICH path : Use this parameter to tell Averno what file must be used as black book. If ommited, Averno will still use AvernoB.libro. Note that you can share a file for different personalities. For exaple, you can use MyBook.white for all your personalities and MyBook_1.black, MyBook_2.black, etc.
VAL_PEON n : Static material value for pawns.
VAL_CABALLO n : Static material value for knights.
VAL_ALFIL n : Static material value for bishops.
VAL_TORRE n : Static material value for rooks.
VAL_DAMA n : Static material value for queens.
When you run Averno, type the name of the personality file (without .per) you want to use after Averno.exe. For example (in Winboard.ini):
Averno MyPersonality /fd=c:\chess\averno
Averno uses two book files, one for white and one for black:
- AvernoB.libro
- AvernoN.libro
Note that B and N stand for Blancas and Negras, which is the spanish for White and Black.
To build a book for Averno you will use two pgn files (without comments or variations, just the moves), which names will be:
Blancas.pgn
Negras.pgn
Blancas.pgn will contain games in which white plays good chess (I hope!) and Negras.pgn the same for black. Of course, you can use the same file, copying and renaming it.
Additionally, you can use the signs ! and ? in the games. Place a ! after a move you want the program to play more often, and a ? after a move you don't want the program to play at all.
When you have your pgn files ready, unzip Av_BookBuilder.exe and copy it to same folder where the pgn's are.
Run Av_BookBuilder.exe and type:
ConstruirL n
where n is the number of full moves to use from every game. Typical is 20 or 25.
The program will parse the pgn files and build the book in memory. After the process is finished, you must save it to disk. Type the command:
GuardarL
which will create two files: AvernoB.libro and AvernoN.libro.
Copy those files to the folder where Averno is.
Important note: For Averno understands the moves in the pgn file, there must be a blank space after the dot:
1. e4 e5 2. Nf3 Nc6 - Correct
1.e4 e5 2.Nf3 Nc6 - Not correct
This will be fixed in future versions.
Averno 0.33 supports all winboard features needed to play, plus:
Analysis Mode
Edit position
EPD Processing using EPD2WB by Bruce Moreland
Pondering.
Email me at smyslov@hotmail.com