gnu1987/gnuchess/CHANGES

			  GNU CHESS HISTORY
		      (current version 1.2.87)


January 2, 1987   -- Stuart Cracraft at UCLA
		     He added a few more Tal games to the collection.

January 2, 1987   -- Jim Aspnes at MIT
		     He contributed MCO variations for the Catalan,
		     Queen's Indian, and Reti openings.

December 29, 1986 -- Jim Aspnes at MIT
		     He contributed all MCO variations of the Najdorf
		     to the opening book.He also contributed a LISP
		     macro (written in GNU Emacs Lisp) to convert
		     xchess game formats to GNU Chess opening book
		     format. 

December 14, 1986 -- Ken Thompson at Bell Labs
		     He contributed almost 200 games by Tal to
		     our collection of Tal-games, bringing the
		     total number of Tal positions in the book
		     to 10,692. Total book positions now 13,207.
		     These reside in bookin, bookin.bdg, bookin.tal.
		     Note that presently, only bookin and bookin.tal
		     can be used. The new Tal positions came in a
		     slightly different format, which we have chosen
		     to adopt as our standard format. All book
		     games in bookin and bookin.bdg will gradually
		     change into the new standard format.

December 11, 1986 -- Stuart Cracraft at UCLA
		     Added "averages" for node-count per move,
		     cpu per move, rate per move to list_history
		     and write_history.
		     New version of Xchess installed.
		     Started typing in Tal games into "bookin.tal".
		     Added "total book positions" printout to "book"
		     and "enter" statistics printout.

December 10, 1986 -- Stuart Cracraft at UCLA
		     Implemented aspiration search in normal
		     alpha-beta search. Speedups of 3% to 40%
		     have been noticed in most positions.
		     Occasionally a slower search will result,
		     but it is thought these are worth the
		     usual speedups.

December 9, 1986  -- Stuart Cracraft at UCLA
		     Fixed minor bug in write_history()
		     Added another Tal game, 2nd game of 1st world
		     championship match with Botvinnik, a Benoni.

December 9, 1986  -- Stuart Cracraft at UCLA
		     Enhanced parallelism. All parallel processors
		     now communicate via a shared data file and
		     are kept running (in idle loops watching the
		     shared data file). This saves us a few seconds
		     on each move since the 'rsh' need not be invoked
		     more than once (at the beginning). Since the
		     shared data file is now implemented, we will
		     next work towards a "parallel anarchy" in which
		     any processor can use any other processor in
		     order to reduce its search. The current scheme
		     with the program being only as fast as its slowest
		     processor, is quite inefficient.

December 1, 1986 --  ASP at MIT Athena
		     Added a couple of Master games from 
		     Modern Chess Openings 12 (a Fischer game,
		     and a Matanovic game).

November 30, 1986 -- Stuart Cracraft at UCLA
		     Added parallelism. Can now handle multiple
		     processors (sharing same disk). Later we will
		     add the capability to use processors not sharing
		     the same disk. Modified README and MAN-PAGE.

November 26, 1986 -- Stuart Cracraft at UCLA
		     Fixed a few bugs in book-mailing mechanism.
		     Fixed a bug regarding situations where only
		     one move is available.
		     Fixed a bug in read_history() that caused
		     Black queenside castles to be mishandled.

November 25, 1986 -- Stuart Cracraft at UCLA
		     Added two pawn heuristics. Reward pawns moving into
		     a phalanx of pawns. A phalanx is two or more
		     horizontally-connected pawns. Likewise, penalize
		     pawns leaving a phalanx of pawns. The penalty for
		     leaving is a little more than the reward for
		     entering.

November 24, 1986 -- Stuart Cracraft at UCLA
		     A user reported an unbelievable bug. Investigation
		     of this bug led to the discovery that GNU Chess was
 		     not picking the move judged best by the tree search
		     in all cases. This resulted in the bug showing
 		     itself which further showed that the program was
		     selecting an inferior move. This may result in an
		     improvement to the program's play.

November 24, 1986 -- Stuart Cracraft at UCLA
		     Added two heuristics. Penalize king moves if
		     the king hasn't castled yet. Also, penalize pawn
		     moves which produce doubled pawns. Should
		     probably have something for isolated pawns
		     too.

November 23, 1986 -- Wayne Christopher at Berkeley
		     New version of X chess display front-end.
		     Fixed bugs include multiple pieces, runs
		     on SUNS & Bobcats, loads saved games.

November 23, 1986 -- Stuart Cracraft at UCLA
		     Cleaned up some minor bugs regarding history.
		     Added "Illegal command" error message at Wayne's
		     request.

November 22, 1986 -- David Goldberg at SUN Microsystems
		     He complained that GNU Chess was memory-hungry.
		     A few minor modifications to hash.c reduced
		     uninitialized data space 87% and text space
		     12%. This should make it easier for GNU Chess
		     to run on small computers.

November 22, 1986 -- Stuart Cracraft at UCLA
		     "read" command was working, but needed
		     additional tweaking so that history
		     array would be printed by list_history().

November 19, 1986 -- Stuart Cracraft at UCLA
		     Added "read" command which reads a history
		     file (game listing) and restores the board
		     to as if the person was still playing that.
		     particular game. Generally cleaned up 
		     history mechanism, made it more orthogonal.
		     Revised README. Added doc to MAN-PAGE.

November 16, 1986 -- Stuart Cracraft at UCLA
		     More opening book bugs found and fixed.
		     Added capability to accept abbreviated-algebraic notation
		     for entering "book" games from files.
		     Added approximately 2500 new positions to
		     opening book from games involving the
		     opening called Blackmar-Diemer Gambit,
		     a hoary line developed by Diemer in
		     Germany years ago.

November 15, 1986 -- Wayne Christopher at Berkeley
		     He modified the move generator, resulting in
		     a 28% speedup.

November 14, 1986 -- Stuart Cracraft at UCLA
		     He documented a lot of the GNU Chess modules
		     with brief comments for each function. More
		     extensive internal documentation may go in
		     later.

November 14, 1986 -- Wayne Christopher at Berkeley
		     He created the Xchess interface for
		     GNU Chess to have windowing with X windows.

November 14, 1986 -- Stuart Cracraft at UCLA
		     He added a "randomization" feature to
		     the opening book. This will cause the
		     program to select randomly from alternate
		     variations whenever -DBEST is removed
		     from Makefile's CFLAGS. If this is not
		     removed, the opening play selects the
		     first move found in the book as it appears
		     "in order" in the human-readable book.

November 14, 1986 -- David Goldberg at SUN Microsystems
		     He responded to a query about dbm(3) which
		     eventually resulted in the fixing of a subtle
		     bug in the book code which was causing the
		     program to sometimes hash to the incorrect
		     address and thereby produce a book move which
		     didn't even exist in the book. Thanks David!

November 14, 1986 -- Stuart Cracraft at UCLA
		     He added the "oboard" routine in util.c. This
		     is the reverse of the already extant "iboard"
		     (same module). These two routines translate
		     between GNU Chess internal format and
		     Forsythe notation.

November 10, 1986 -- Stuart Cracraft at UCLA
		     He added the "enter" command. This causes
		     the current game to be entered in the book.
		     Then, GNU Chess tries to mail this new entry
		     to the book maintainers (for inclusion in
		     the master copy of the book).

November 9, 1986 -- Stuart Cracraft at UCLA
		    He added code for an opening book. MAN-PAGE
		    and README were modified accordingly.

November 8, 1986 -- Stuart Cracraft at UCLA
		    Checks and mates are now noticed at ply-1.
		    This is a more complete fix to the Oct 31 fix.

October 31, 1986 -- Stuart Cracraft at UCLA
		    First attempt at fix to bug which causes
		    program to check human's king when program
		    itself is in check.

October 31, 1986 -- Mly at MIT
		    Reported a bug which caused program to crash
		    when an illegal human move was played. Fixed.
		    Also, program was unable to play as White. Fixed.

October 22, 1986 -- Stuart Cracraft at UCLA
		    Pps now rewards moves which liberate bishops.

October 19, 1986 -- Stuart Cracraft at UCLA
		    Added bitmapper routines to distribution.
		    Added version notice.

October 19, 1986 -- David Goldberg at SUN Microsystems
		    Interfaced GNU Chess with SUN's chesstool.

October 18, 1986 -- Initial release date.