HexAbSearch Class Reference

Base Alpha-Beta search class. More...

#include <HexAbSearch.hpp>

Inheritance diagram for HexAbSearch:

Classes
struct	Statistics
	Search statistics. More...
Public Member Functions
	HexAbSearch ()
	Constructor.
virtual	~HexAbSearch ()
	Destructor.
void	SetTT (SearchTT *tt)
	Sets the transposition table to be used during search.
bool	GuiFx () const
	Writes progress of search in guifx format after each root move completes.
void	SetGuiFx (bool flag)
	Sets whether guifx output should be dumped.
HexEval	Search (HexBoard &brd, HexColor color, const std::vector< int > &plywidth, const std::vector< int > &depths_to_search, int timelimit, std::vector< HexPoint > &PV)
	Runs the AlphaBeta search.
virtual HexEval	Evaluate ()=0
	Evaluates leaf position.
virtual void	GenerateMoves (std::vector< HexPoint > &moves)=0
	Generates moves for this position.
virtual void	ExecuteMove (HexPoint move)=0
	Plays the given move.
virtual void	UndoMove (HexPoint move)=0
	Undoes the given move.
virtual void	EnteredNewState ()
	Hook function called upon entering new position.
virtual void	OnStartSearch ()
	Hook function called at the very start of the search.
virtual void	OnSearchComplete ()
	Hook function called after the search has completed.
virtual void	AfterStateSearched ()
	Hook function called after a states moves have been searched.
std::string	DumpStats ()
	Output stats from search.
Protected Attributes
HexBoard *	m_brd
	The board we are playing on.
HexColor	m_toplay
	Color of player to move next.
SearchTT *	m_tt
	Transposition table to use during search, if any.
bool	m_use_guifx
int	m_current_depth
	Number of moves from the root.
PointSequence	m_sequence
	Sequences of moves to the current state.
HexPoint	m_tt_bestmove
	If current state exists in TT, but TT state was not deep enough, this will hold the best move for that state; otherwise it will be INVALID_MOVE.
bool	m_tt_info_available
Private Member Functions
void	ClearStats ()
void	UpdatePV (int current_depth, HexEval value, std::vector< HexPoint > &cv)
HexEval	CheckTerminalState ()
bool	CheckAbort ()
	Checks SgUserAbort() and sets m_aborted if true.
HexEval	SearchState (const std::vector< int > &plywidth, int depth, HexEval alpha, HexEval beta, std::vector< HexPoint > &cv)
Private Attributes
Statistics	m_statistics
std::vector< HexMoveValue >	m_eval
	Evaluations for each move from the root state.
bool	m_aborted
	True if the search was aborted due to timelimit or user intervention.

Detailed Description

Base Alpha-Beta search class.

Definition at line 25 of file HexAbSearch.hpp.

Constructor & Destructor Documentation

HexAbSearch::HexAbSearch ( ) [explicit]

Constructor.

Definition at line 74 of file HexAbSearch.cpp.

HexAbSearch::~HexAbSearch ( ) [virtual]

Destructor.

Definition at line 81 of file HexAbSearch.cpp.

Member Function Documentation

void HexAbSearch::AfterStateSearched ( ) [virtual]

Hook function called after a states moves have been searched.

Default implementation does nothing.

Reimplemented in WolveSearch.

Definition at line 93 of file HexAbSearch.cpp.

Referenced by SearchState().

bool HexAbSearch::CheckAbort ( ) [private]

Checks SgUserAbort() and sets m_aborted if true.

Definition at line 181 of file HexAbSearch.cpp.

References LogInfo(), and m_aborted.

Referenced by SearchState().

HexEval HexAbSearch::CheckTerminalState ( ) [private]

Definition at line 170 of file HexAbSearch.cpp.

References IMMEDIATE_LOSS, IMMEDIATE_WIN, EndgameUtils::IsLostGame(), EndgameUtils::IsWonGame(), m_brd, m_current_depth, and m_toplay.

Referenced by SearchState().

void HexAbSearch::ClearStats ( ) [private]

std::string HexAbSearch::DumpStats ( )

Output stats from search.

Definition at line 379 of file HexAbSearch.cpp.

References HexAbSearch::Statistics::Dump(), m_eval, and m_statistics.

Referenced by WolvePlayer::Search().

void HexAbSearch::EnteredNewState ( ) [virtual]

Hook function called upon entering new position.

Default implementation does nothing.

Reimplemented in WolveSearch.

Definition at line 87 of file HexAbSearch.cpp.

Referenced by SearchState().

virtual HexEval HexAbSearch::Evaluate ( ) [pure virtual]

Evaluates leaf position.

Implemented in WolveSearch.

Referenced by SearchState().

virtual void HexAbSearch::ExecuteMove ( HexPoint move ) [pure virtual]

Plays the given move.

Implemented in WolveSearch.

Referenced by SearchState().

virtual void HexAbSearch::GenerateMoves ( std::vector< HexPoint > & moves ) [pure virtual]

Generates moves for this position.

Moves will be played in the returned order.

Implemented in WolveSearch.

Referenced by SearchState().

bool HexAbSearch::GuiFx ( ) const [inline]

Writes progress of search in guifx format after each root move completes.

Off by default.

Definition at line 200 of file HexAbSearch.hpp.

References m_use_guifx.

Referenced by WolveEngine::WolveParam().

void HexAbSearch::OnSearchComplete ( ) [virtual]

Hook function called after the search has completed.

Default implementation does nothing.

Reimplemented in WolveSearch.

Definition at line 91 of file HexAbSearch.cpp.

Referenced by Search().

void HexAbSearch::OnStartSearch ( ) [virtual]

Hook function called at the very start of the search.

Default implementation does nothing.

Reimplemented in WolveSearch.

Definition at line 89 of file HexAbSearch.cpp.

Referenced by Search().

HexEval HexAbSearch::Search	(	HexBoard &	brd,
		HexColor	color,
		const std::vector< int > &	plywidth,
		const std::vector< int > &	depths_to_search,
		int	timelimit,
		std::vector< HexPoint > &	PV
	)

Runs the AlphaBeta search.

Parameters:

	brd	board to play one.
	color	color to play.
	plywidth	depth of the search set to plywidth.size() and plywidth[j] top moves are explored.
	depths_to_search	successive depths to search (like in ID).
	timelimit	amount of time in which to finish search.
	PV	the principal variation will be stored here.

Returns:: the evaluation of the PV.

If search is aborted by the user or the timelimit is reached, then the last valid result from interative deepening is returned. If the first iteration has not completed, then a score of -EVAL_INFINITY and a PV containing only INVALID_POINT are returned.

Definition at line 95 of file HexAbSearch.cpp.

References HexAbSearch::Statistics::elapsed_time, EVAL_INFINITY, Get(), IMMEDIATE_LOSS, IMMEDIATE_WIN, INVALID_POINT, LogInfo(), m_aborted, m_brd, m_current_depth, m_eval, m_sequence, m_statistics, m_toplay, OnSearchComplete(), OnStartSearch(), HexAbSearch::Statistics::pv, SearchState(), UNUSED(), and HexAbSearch::Statistics::value.