Latista 1.5

[eric_oldre]

I have just released Latista 1.5. I would guess it is about 50 to 100 points stronger than 1.4. It can be downloaded at my homepage.

Daniel Shawal made an update to the endgame bitbases about 2 weeks ago. You can download the fixed version either from my site or from his.

Thanks to everyone to gives it a try!

Eric

(readme file contents)

Latista 1.5
Release Date Jan 14th, 2006
Homepage http://www.oldre.com/chess/latista/

A chess program written by Eric Oldre.


*********** LICENSE ****************************
Latista is free for personal use.


*********** HOW DO I PLAY? *********************
Latista supports the xboard chess engine protocol. This means
that you need a graphical user interface (GUI) in order to
be able to play against it. Examples of some interfaces that
you can use to play Latista are:

-Winboard http://www.tim-mann.org/xboard.html
-Arena http://www.playwitharena.com/


*********** HOW STRONG IS LATISTA 1.5 *************

Latista plays on the Free Internet Chess Server (FICS)
whenever my computer is free. It plays under the handle
"Murderhole". It has a rating of about 2100. If you'd like
to play it go to http://www.freechess.org.


*********** HOW DOES LATISTA WORK? *************
board representation:
Latista is a chess engine built on the concept of
rotated bitboards, a concept developed by Robert Hyatt.
Information about them can be found at:
http://www.cis.uab.edu/info/faculty/hyatt/pubs.html

search features:
Latista uses a Alpha-Beta search algorithim with several
enhancements which include:
-Iterative deepening.
-Aspiration window.
-Null move cutoffs
-Quiesent search (captures and promotions only)
-Move ordering by:
-Hash table entries
-Internal Iterative deepening
-Static exchange evaluation
-Killer moves
-Fractional extensions for:
-Checks
-Pawn to 7th rank.
-futility pruning
-reductions based on several factors.

Evaluation features:
-Material
-Pawn hash table
-Piece square table
-Pawn shelter for king
-King safety
-Pawn Races
-Development
-Piece Activity



*********** WHAT HAS CHANGED SINCE 1.4 *************
1) Latista nows uses more agressive null move
pruning. R=3, with a verification search in the endgame

2) The evaluation function has been tweaked with a few
special cases. Other parts have been simplified to make
a more smooth transition from the middle to end game.

3) New configuration option: [book]selectivity. The higher
the number the "closer to the vest" Latista will play during
the opening. With a value of 100 it will always play the most
popular move in it's book.

4) New configuration option: [logging]createlogfile (1 or 0).
Now you have the option to not create a log file and conserve
hard disk space.

5) Changes to the way Latista handles searching on a "ponderhit".
It will now simply continue the ponder search, instead of restarting.
This should increase it effectiveness in game with pondering on.


*********** HOW DO I USE THE ENDGAME BITBASES ****************
1) Download the endgame bitbase dll and data files (available at oldre.com)
2) Put the file in some directory on your PC. Put both the dll and data
files in the same directory.
3) Edit the latista.ini file, enter the location of the files
in the [egbb] section under "path".


*********** SPECIAL THANKS TO ****************

The members of the computer chess club. (http://www.talkchess.com/)
All the directors of winboard engine tournaments.
Jim Ablett for creating the Latista logo image.
Daniel Shawul for developing the shared endgame bitbase library.