An Experimental Chess Program

Page last updated: March 29, 2013

Some History

I started EXchess (short for “Experimental Chess Program”) back in 1996 as a way to learn programming and to have a hobby to work on. EXchess was very successful on both counts, and I developed it in my spare time until I had to write my PhD in 1999. Since that time EXchess has mostly sat on the “shelf”, but I still find time to work on it now and again. The current release includes source code that can be compiled on a variety of systems to run in ‘text’ mode or under an Xboard/Winboard compatible graphic interface. A stand-alone version with a simple graphical interface, suitable for casual human-computer play, is also available.

Features

EXchess is an amateur chess program that can be run in plain text mode or it can be interfaced with standard graphical chess interface programs like Xboard/Winboard or Arena. The main features of EXchess are…

· Advanced search algorithms including principle variation search, null move, dynamic search extensions, hash tables, history tables, quiescence search, material swap function, interface with Namilov endgame tablebases, late move reductions, chess skill setting, and context specific evaluation.

· Opening book learning (off by default: for play against other computers, this should be turned on by editing the “search.par” file).

· You can modify how EXchess thinks by editing the search.par file that comes with the program. (Note that previous versions had a 'score.par' file as well for TDleaf learning, but I am no longer using TDleaf learning in version 6.30 and later.)

· You can download the source code for EXchess. You are free to modify the source code under the terms of the GNU Public License.

See the readme file for more details.

Downloads

EXchess is released under the GNU Public License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

EXchess is beta quality software, meaning that it has not been extensively tested on a wide variety of systems and may still contain bugs. Use it at your own risk. If you encounter any bugs, please let me know, and I will fix them as I have the time, but please understand that my time to work on this project is limited, so I may not respond with bug-fixes immediately.

Text/Console Version with Source Code and Executables

(Note: Executables are for some systems only, see readme.txt)

· EXchess v7.03 beta, click here

Simple Graphical Version

The included graphical interface is based upon the Checkers example program by Bill Spitzak in the Fast Light Tool Kit (FLTK). This version is fine for casual human-computer games, but I strongly recommend the Xboard/Winboard or Arena programs, combined with the text/console version above, for a much more full-featured graphical interface.

· Simple Graphical Version of EXchess v7.03 beta for Windows 7, click here

· Simple Graphical Version of EXchess v7.03 beta for MacOS 10.6.8, click here

See the included readme.txt file for instructions on how to compile and run EXchess.