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Readme: 

Myrddin v0.81 Alpha 2 Release Notes -- 5/26/09
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Myrddin is a winboard-compliant chess engine to a reasonable degree. It supports 
protover 1 primarily to support the Chessmaster interface, and also protover 2. 

Alpha 2 plays approximately 1600-1700 ELO against chess engines, and probably 
100-200 points higher against humans. This is an improvement of approximately 
400 points compared to Alpha 1.

Its most recent tournament performance, in the promotional division of ChessWar 
XIV (www.open-aurec.com/chesswar), was rated at 1655 over 11 rounds. Myrddin 
scored 6.5 points (+5 =3 -3) and placed 51st out of 212 engines rated between 
1859 and 812. The median engine rating was 1499.

The following winboard commands are supported:
protover
new
go
?
analyze
playother
setboard
force
white/black
time/otim
level
hard/easy
result
undo/remove
post/nopost
quit/exit

Myrddin also supports "eval", which returns a static evaluation of the current
game position, and "perft N", where 'N' is the perft depth requested. Neither 
of these are supported during a search.

Winboard UI notes: 
-- It is crucial that the winboard UI being used send the "time" command to the
    engine, as Myrddin does not have an internal clock.  
-- Pondering is ON by default.
-- Post is ON by default, as opposed to the winboard protocol. This is just for
    debugging convenience.

General Notes:
-- Evaluation is rather simple: wood counting, piece square tables, pawn 
    structure, king safety, rooks behind passers, and some knowledge about 
    minor piece placement in relation to pawns. There's a long way to go here.
-- Search is basic alpha/beta, with reasonable extensions for check, capture,
    promotion and positions that have very few legal moves.
-- Max search depth is 30. 
-- The ProDeo opening book is used by kind permission of Ed Schröder.
-- Draw claims from the opponent are not supported, nor does Myrddin know how 
    to claim a draw.
-- There is just enough winboard support to play games on ICS. But without 
    support for "draw" offers, I'm sure there are some scary loopholes and/or 
    exploits. 
-- When the engine is in analysis mode, positive scores always favor White and
    negative scores always favor Black. When the engine is thinking or 
    pondering, positive moves favor Myrddin.
-- A logfile called "Myrddin-T.log" is automatically created with every program
    run, where "T" is the system clock time. The output of the log is not very 
    interesting at this time -- mostly just communication reality-check stuff.

FULL DISCLOSURE: The move generation code was "heavily borrowed" from the
Chessmaster UI, but I feel that this is not "cloning" as I worked on that title
for many years. Also, the code has been improved a fair bit, and is now about 
30% faster than the original code.  

Many thanks to the following brilliant people who helped/guided me (either 
directly or indirectly) in countless ways with their work:
TSCP -- Tom Kerrigan
Firstchess -- Pham Hong Nguyen
Greko -- Vladimir Medvedev
Crafty -- Dr. Robert Hyatt
Gerbil -- Bruce Moreland
Belofte -- Yves Debilloez
Chessmaster -- Lots of brilliant people, but mostly Johan de Koning (programmer 
    of The King engine), Don Laabs (programmer of many of the low-level chess 
    UI routines, including the move generator), James Stoddard (programmer of 
    Chessmaster Live, the winboard UI support, and most of the game-handling 
    routines) and Dave Cobb (programmer of the opening book editor and many 
    other support features).

Version List
---------------
v0.80 Alpha 1, released on 3/9/09
Initial Release

v0.81 Alpha 2, released on 5/26/09
Change List:
-- Greatly improved move generation speed (perft 6 on initial position has gone
    from 57 to 41 seconds on P4-3.0)
-- Search now pings the input command handler every 8K nodes (about 1/30-1/50 
    second, depending on position and hardware), so applicable commands can now 
    be entered during search/analysis
-- Search will allocate extra thinking time when it gets noticeable drop in 
    score
-- Evaluation improvements -- pawn structure, open and semi-open files for 
    rooks, rooks behind passers, king safety
-- Added MVV/LVA and PV Move Ordering
-- Added Killer and History move ordering heuristics
-- Added Null Move reductions
-- Added Late Move reductions
-- Added Opening Book (ProDeo -- Thanks, Ed!)
-- Added pondering, so "hard" and "easy" commands are now supported
-- "analyze", "?" and "result" commands are now supported
-- "level" command is now fully supported for all time control types
-- Added check for dirty pawn structure before evaluation
-- Search can be interrupted due to time management considerations
-- Added Hash Tables, with a fixed size of 128MB
-- Maximum search depth increased from 20 to 30
-- Fixed a bug with evaluating castling moves
-- Fixed a bug determining which King piece table to use
-- Can now generate capturing moves only so quiescent search has less moves to
    sort/deal with
-- Quiescent moves are added to PV
-- Added code for pushing lone King towards edge of board
-- Added material and 50-move draw detection
-- Fixed a bug in the "undo" and "remove" commands
-- Scores in analyze mode will always be positive if White is winning and 
    negative if Black is winning
-- Fixed some bugs in the 3-fold repetition detection
-- Fixed a stupid bug that caused me to check for user input WAY too often -- 
    many thanks to Bob Hyatt for pointing me in the right direction
-- Significant code cleanup

Known Problems:
-- Analyze mode can crash using an "undo", possibly only after a "setboard"
    command has been received 

To do for next release, in approximate order of priority
-- better quiescent search pruning/reductions
-- outposts and escape routes
-- improve king safety eval
-- draw claims -- sending and receiving
-- SEE
-- come up with better way to define changes from opening/middlegame/endgame
-- commandline options (hash table size, turn off logfile, etc.)
-- edit mode (primarily for supporting the Chessmaster GUI)
-- Ping

Please send bug reports and general suggestions/comments to JVMerlino@aol.com.
If you wish to enter Myrddin into one of your own tournaments, please feel free
to do so! But please let me know so I can follow the tournament.

Thanks for playing!

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