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Created page with "'''Home * Engines * CPW-Engine * History''' =December 2014, Version 1.1= * LMR added * Reverse Futility Pruning|eval pruning..."
'''[[Main Page|Home]] * [[Engines]] * [[CPW-Engine]] * History'''
=December 2014, Version 1.1=
* [[Late Move Reductions|LMR]] added
* [[Reverse Futility Pruning|eval pruning]] added
* major cleanup of evaluation function
* new king attack function
* new [[Futility Pruning|futility pruning]] restrictions
=September 2008=
==05.09.2008==
* display of book alternatives
* FIX concerning illegal book moves
* NEW: book moves can be selected by their frequency
==04.09.2008==
* a couple of int functions whose returned value has not been used renamed to voids
* clearing of the search driver now done in search_run, not in time_xxx_go
* more comments
==03.09.2008==
* in search procedures renamed smove m[256] to smove movelist[256];
: "m" should be reserved for a single move
* move_isPseudoLegal() replaced by move_isLegal() which tests for check
==02.09.2008==
* NEW: search_iterate() stops on one legal reply after searching to depth 4
* new names and location of functions move_isPseudoLegal() and move_countLegal()
* more comments in search.cpp
* separated book.h
* FIX: replies to moves excluded from the opening book ( again )
=August 2008=
==29.08.2008==
* small internal book (in case that book file is missing)
* FIX: timing-bug
==27.08.2008==
* FIX: various bugs occuring in fast time controls
* only legal moves are checked at the root
* FIX: hash memory allocation change possible
: total memory = hash + hash/4(pawn hash) + 4mb(opening book, etc)
* FIX: communication bug, stealing cpu of opponent
* FIX: en passant flag is not set when no pawn can execute en-passant capture
: ( which helps with opening book and increases the number of transposition table cutoffs )
* change in delta pruning
* a couple of range checks added
* numerous opening book code fixes
* simplification of move parsing routine
* because of ChessWar, reintroduced badCapture() pruning in quiescence search
==26.08.2008==
* NEW: program can use a TSCP-like book, exclude some moves out of it and handle transpositions
* changed time management + comments
==26.08.2008==
* NEW: program can use a TSCP book and handle transpositions
==25.08.2008==
* FIX: removed all compiler-warnings (more attention given to variable types)
* FIX: correct output of mate-values
* FIX: transposition-table crash fixed, when size set to 0
* FIX: ==/= bug in eval.cpp
* encapsulation of useKiller
* slight changes with futility-pruning
* created header file for transposition-table
* NEW: 4% speedup through prefetching the transpositiontable entry
==22.08.2008==
-FIX in pawn shield evaluation "=" replaced by "==" (aaargh!)
==21.08.2008==
* new pruning in QS (testing if a queen capture and/or promotion can improve alpha)
==19.08.2008==
* NEW: evaluation hashtable (currently disabled, since lazy eval performs much better,
but might become useful after a rewrite of evaluation function)
* finding good configuration of compiler switches
==17.08.2008==
* further restructuring of search routines
* NEW: aspiration search
==16.08.2008==
* separating setKillers() function
==12.08.2008==
* serious restructuring of root search functions (sepatating search_root and search_iterate)
==10.08.2008==
-FIX: hash moves from lower depths used for sorting
==08.08.2008==
* NEW: contempt() function instead of constant
==07.08.2008==
* NEW: adaptative null move pruning
* FIX: loop counter for killer moves initialized as 0, not as 1 (bad Pascal habits!)
* FIX: in info_currmove() first move number is 1, not 0 (bad C habits!)
* in search() variable move_to_make instead of a loop redetecting best move
* in movegen.ccp vectors represented as constants (NE etc) not as numbers
* in movegen.cpp unnecessary int functions changed to void
* getting rid of is_futility compiler switch
==05.08.2008==
* NEW: Pawn-hashtables
* NEW: fast_eval()
* because of that changes futility pruning gives some benefit, so it's enabled now
* added move_iscapt() and move_isprom() to improve readability
==04.08.2008==
* NEW: function slavMistake() that discourages blocking the center
* NEW: futility pruning (currently disabled, as node savings do not offset speed loss)
=July 2008=
==03.08.2008==
* separating com_nothing() function
* more customizable evaluation parameters
==30.07.2008==
* NEW: CPW.ini stores evaluation constants
* Transposition table: The size is scaled down to the next lower power of 2
* thus replacing the slow mod operation by a quick 'and' operation when generating the tt-index
* reducing the tt-entry size from 24 to 16 bytes. (changing alignment)
* stop tt_save from overwriting an entry with the same position of a shallower depth
* com (uci-protocol): 'setoption name Hash value n' works now
==28.07.2008==
* TWEAK: reducing a score jump caused by castling
* TWEAK: bringing down mobility scores and second lazy evaluation limit
* TWEAK: penalty for the lack of pawns
==26.07.2008==
* TWEAK: raising piece/square scores
* TWEAK: modification of evalFianchetto()
==22.07.2008==
* NEW: [[History Heuristic|history heuristic]]
* TWEAK: doubled pawns do not count as a double king's shield
* TWEAK: expanded pawn center evaluation: support for e4 pawn also counts
==21.07.2008==
* NEW: basic fianchetto evaluation
* NEW: console interface will accept only pseudo-legal moves
==20.07.2008==
* NEW: killer heuristics (ugly code in need of redesign, but gains a couple of percent nodes)
* FIX: nodes per second calculation overflow problem fixed
* NEW: more human-friendly output in console mode
==19.07.2008==
* NEW: console mode reacts to "st" and "sd" commands
==18.07.2008==
* separating the eval.h file for function not used outside eval.cpp (better encapsulation)
* making use of 088_math.h and changing most of its functions into macros
* TWEAK: rooks on open files near the king increase tropism
* scaling of middlegame king evaluation affects also pcsq score
* creating a eval_vect struct collecting partial scores
* serious restructuring of eval.cpp
* creating printEval() function giving some insight into evaluation components
* FIX: fixed a bug with [[delta pruning]] (it does not prune promotions anymore)
==11.07.2008==
* better time management
* FIX: time check done once every 1024 nodes, not in each node - massive speedup
* optimization of doubled pawn eval (a table instead of multiple ifs)
==10.07.2008==
* NEW: [[Principal Variation Search|PVS]] added
* FIX: a check extension also at the root (hash results from a move ago will be used more consistently)
* separated PIECE_VAL and SORT_VAL, simplifying the code and getting rid of problems with king value
* in fillSq() and clearSq() the count of pawns on a file is kept, so doubled pawns and open files are finally evaluated
* fillSq() and clearSq() don't update piece/square value for a king (this is done within eval.cpp)
==01.07.2008==
* FIX: check extension bug fixed
=June 2008=
==30.06.2008==
* FIX: leaf node hashing bug fixed
* some move sorting experiments
==29.06.2008==
* repetition detection - from now on CPW becomes a chess engine (as opposite to almost-chess engine)
* FIX: solved the bug with the hash-values when time is over (tt_save only saves the hash, when time_over == false)
* FIX: solved the bug with the communication
* [[Null Move Pruning|null move]] implemented
'''[[CPW-Engine|Up one Level]]'''
=December 2014, Version 1.1=
* [[Late Move Reductions|LMR]] added
* [[Reverse Futility Pruning|eval pruning]] added
* major cleanup of evaluation function
* new king attack function
* new [[Futility Pruning|futility pruning]] restrictions
=September 2008=
==05.09.2008==
* display of book alternatives
* FIX concerning illegal book moves
* NEW: book moves can be selected by their frequency
==04.09.2008==
* a couple of int functions whose returned value has not been used renamed to voids
* clearing of the search driver now done in search_run, not in time_xxx_go
* more comments
==03.09.2008==
* in search procedures renamed smove m[256] to smove movelist[256];
: "m" should be reserved for a single move
* move_isPseudoLegal() replaced by move_isLegal() which tests for check
==02.09.2008==
* NEW: search_iterate() stops on one legal reply after searching to depth 4
* new names and location of functions move_isPseudoLegal() and move_countLegal()
* more comments in search.cpp
* separated book.h
* FIX: replies to moves excluded from the opening book ( again )
=August 2008=
==29.08.2008==
* small internal book (in case that book file is missing)
* FIX: timing-bug
==27.08.2008==
* FIX: various bugs occuring in fast time controls
* only legal moves are checked at the root
* FIX: hash memory allocation change possible
: total memory = hash + hash/4(pawn hash) + 4mb(opening book, etc)
* FIX: communication bug, stealing cpu of opponent
* FIX: en passant flag is not set when no pawn can execute en-passant capture
: ( which helps with opening book and increases the number of transposition table cutoffs )
* change in delta pruning
* a couple of range checks added
* numerous opening book code fixes
* simplification of move parsing routine
* because of ChessWar, reintroduced badCapture() pruning in quiescence search
==26.08.2008==
* NEW: program can use a TSCP-like book, exclude some moves out of it and handle transpositions
* changed time management + comments
==26.08.2008==
* NEW: program can use a TSCP book and handle transpositions
==25.08.2008==
* FIX: removed all compiler-warnings (more attention given to variable types)
* FIX: correct output of mate-values
* FIX: transposition-table crash fixed, when size set to 0
* FIX: ==/= bug in eval.cpp
* encapsulation of useKiller
* slight changes with futility-pruning
* created header file for transposition-table
* NEW: 4% speedup through prefetching the transpositiontable entry
==22.08.2008==
-FIX in pawn shield evaluation "=" replaced by "==" (aaargh!)
==21.08.2008==
* new pruning in QS (testing if a queen capture and/or promotion can improve alpha)
==19.08.2008==
* NEW: evaluation hashtable (currently disabled, since lazy eval performs much better,
but might become useful after a rewrite of evaluation function)
* finding good configuration of compiler switches
==17.08.2008==
* further restructuring of search routines
* NEW: aspiration search
==16.08.2008==
* separating setKillers() function
==12.08.2008==
* serious restructuring of root search functions (sepatating search_root and search_iterate)
==10.08.2008==
-FIX: hash moves from lower depths used for sorting
==08.08.2008==
* NEW: contempt() function instead of constant
==07.08.2008==
* NEW: adaptative null move pruning
* FIX: loop counter for killer moves initialized as 0, not as 1 (bad Pascal habits!)
* FIX: in info_currmove() first move number is 1, not 0 (bad C habits!)
* in search() variable move_to_make instead of a loop redetecting best move
* in movegen.ccp vectors represented as constants (NE etc) not as numbers
* in movegen.cpp unnecessary int functions changed to void
* getting rid of is_futility compiler switch
==05.08.2008==
* NEW: Pawn-hashtables
* NEW: fast_eval()
* because of that changes futility pruning gives some benefit, so it's enabled now
* added move_iscapt() and move_isprom() to improve readability
==04.08.2008==
* NEW: function slavMistake() that discourages blocking the center
* NEW: futility pruning (currently disabled, as node savings do not offset speed loss)
=July 2008=
==03.08.2008==
* separating com_nothing() function
* more customizable evaluation parameters
==30.07.2008==
* NEW: CPW.ini stores evaluation constants
* Transposition table: The size is scaled down to the next lower power of 2
* thus replacing the slow mod operation by a quick 'and' operation when generating the tt-index
* reducing the tt-entry size from 24 to 16 bytes. (changing alignment)
* stop tt_save from overwriting an entry with the same position of a shallower depth
* com (uci-protocol): 'setoption name Hash value n' works now
==28.07.2008==
* TWEAK: reducing a score jump caused by castling
* TWEAK: bringing down mobility scores and second lazy evaluation limit
* TWEAK: penalty for the lack of pawns
==26.07.2008==
* TWEAK: raising piece/square scores
* TWEAK: modification of evalFianchetto()
==22.07.2008==
* NEW: [[History Heuristic|history heuristic]]
* TWEAK: doubled pawns do not count as a double king's shield
* TWEAK: expanded pawn center evaluation: support for e4 pawn also counts
==21.07.2008==
* NEW: basic fianchetto evaluation
* NEW: console interface will accept only pseudo-legal moves
==20.07.2008==
* NEW: killer heuristics (ugly code in need of redesign, but gains a couple of percent nodes)
* FIX: nodes per second calculation overflow problem fixed
* NEW: more human-friendly output in console mode
==19.07.2008==
* NEW: console mode reacts to "st" and "sd" commands
==18.07.2008==
* separating the eval.h file for function not used outside eval.cpp (better encapsulation)
* making use of 088_math.h and changing most of its functions into macros
* TWEAK: rooks on open files near the king increase tropism
* scaling of middlegame king evaluation affects also pcsq score
* creating a eval_vect struct collecting partial scores
* serious restructuring of eval.cpp
* creating printEval() function giving some insight into evaluation components
* FIX: fixed a bug with [[delta pruning]] (it does not prune promotions anymore)
==11.07.2008==
* better time management
* FIX: time check done once every 1024 nodes, not in each node - massive speedup
* optimization of doubled pawn eval (a table instead of multiple ifs)
==10.07.2008==
* NEW: [[Principal Variation Search|PVS]] added
* FIX: a check extension also at the root (hash results from a move ago will be used more consistently)
* separated PIECE_VAL and SORT_VAL, simplifying the code and getting rid of problems with king value
* in fillSq() and clearSq() the count of pawns on a file is kept, so doubled pawns and open files are finally evaluated
* fillSq() and clearSq() don't update piece/square value for a king (this is done within eval.cpp)
==01.07.2008==
* FIX: check extension bug fixed
=June 2008=
==30.06.2008==
* FIX: leaf node hashing bug fixed
* some move sorting experiments
==29.06.2008==
* repetition detection - from now on CPW becomes a chess engine (as opposite to almost-chess engine)
* FIX: solved the bug with the hash-values when time is over (tt_save only saves the hash, when time_over == false)
* FIX: solved the bug with the communication
* [[Null Move Pruning|null move]] implemented
'''[[CPW-Engine|Up one Level]]'''
