This is unrelated to Brain Aid Prolog, but is a chess implementation for standard prolog compilers. It has been tested on SWI-Prolog, BinProlog and was reported to run on Sictus, as well as on Quintus with a minor change in the source. You'll find more details as well as the archive below.
The program uses a tree-search algorithm with so called Alpha-Beta cutting. The basic Idea is to generate all moves up to a certain depth, then to estimate the value of that position (position-rating) for the white player. Alpha-Beta cutting reduces the number of positions to be evaluated by about a half, by logically eliminating the need to examine all positions. You should be able to find easily literature on that topic.
The overall performance of the program is rather poor. If I had to recode a chess program nowadays in prolog, I would now try to reduce the number of database usage.
If you are just interested in playing chess, you'll rather want to look at GNU Chess.
Prolog Chess Version 1.2, 25.7.95 --------------------------------- Ported by Martin Ostermann to 'standard' Prolog on a Quick+Dirty base. Changes made: = to is = to =:= " to ' <= to =< div to // INCLUDE to :- [..] Also the GUI Interface has been replaced by a tty version, with no display of the board, just moves. It has been tested on SWI-Prolog-2.1.0 and BinProlog-3.30. Also with a small edit in chess_12.pl (described there) it was reported to run on Quintus Prolog 3.1.4. Load with '[chess_12].' and start with 'run.' NOTE: Casteling has not jet been implemented. More detailed notes offered at 'http://www.cs.tu-berlin.de/~fraber/chess/chess.html'. This archive (*.tar.gz / ZIP) contains the following files: chess_12.pl globals.pl pos_val.pl read.me stack.pl zug_gen.pl license The read.me file of the original is appended:
Prolog Chess Version 1.1, 3.8.89 -------------------------------- Version for Turbo Prolog The program comes with two different graphic drivers that either support text graphics or the BGI interface. For this purpose, two versions of the "graphics" file exist, one for text graphics ("graphics.std") and one for the BGI interface ("graphics.ega"). Please copy the relevant file to "graphics.pro" and compile the file "chess_11.pro" which contains the main predicates. Comments and suggestions are highly appreciated. If you should port this program to other platforms, please drop me a note, so that I can put a link to your site onto my page. Frank Bergmann
http://www.cs.tu-berlin.de/~fraber This is the listing of the directory where we compiled the program: bgi.lib 60416 1.01.89 2:00 The BGI Library from Borland egavga.bgi 5363 1.01.89 2:00 The BGI driver figb_w.fig 72556 17.12.89 20:07 The images of Helmut Kohl and Maggy Thatcher globals.pro 1884 3.08.92 16:10 Global predicates goth.chr 8560 1.01.89 2:00 BGI font graphics.ega 4398 3.08.92 15:03 EGA output driver graphics.std 4472 3.08.92 15:10 Text-mode output driver litt.chr 2138 1.01.89 2:00 BGI font pos_val.pro 2347 3.08.92 16:20 Position evaluation sans.chr 5438 1.01.89 2:00 BGI font chess_11.pro 14654 3.08.92 16:31 The main program stack.pro 785 3.08.92 16:19 Stack management trip.chr 7241 1.01.89 2:00 BGI font zug_gen.pro 4968 3.08.92 16:39 Move-generator