ChessEngine Class Reference

An artificial intelligence chess player. More...

#include <chessengine.h>

Inheritance diagram for ChessEngine:

Public Types
enum	WriteMode { Buffered, Unbuffered }
Public Types inherited from ChessPlayer
enum	State {   NotStarted, Starting, Idle, Observing,   Thinking, FinishingGame, Disconnected }

Public Slots
virtual void	go ()
virtual void	kill ()
virtual void	quit ()
Public Slots inherited from ChessPlayer
virtual void	go ()
virtual void	kill ()
virtual void	quit ()

Public Member Functions
void	applyConfiguration (const EngineConfiguration &configuration)
	ChessEngine (QObject *parent=nullptr)
QIODevice *	device () const
virtual void	endGame (const Chess::Result &result)
virtual bool	isHuman () const
virtual bool	isReady () const
QList< EngineOption * >	options () const
void	ping (bool sendCommand=true)
virtual QString	protocol () const =0
void	setDevice (QIODevice *device)
void	setOption (const QString &name, const QVariant &value)
void	start ()
virtual bool	supportsVariant (const QString &variant) const
QStringList	variants () const
void	write (const QString &data, WriteMode mode=Buffered)
Public Member Functions inherited from ChessPlayer
void	addTime (int bonus)
bool	areClaimsValidated () const
	ChessPlayer (QObject *parent=nullptr)
virtual void	clearPonderState ()
QString	errorString () const
const MoveEvaluation &	evaluation () const
bool	hasError () const
virtual void	makeBookMove (const Chess::Move &move)
virtual void	makeMove (const Chess::Move &move)=0
QString	name () const
void	newGame (Chess::Side side, ChessPlayer *opponent, Chess::Board *board)
void	setCanPlayAfterTimeout (bool enable)
void	setClaimsValidated (bool validate)
void	setName (const QString &name)
void	setTimeControl (const TimeControl &timeControl)
Chess::Side	side () const
virtual void	startPondering ()
State	state () const
const TimeControl *	timeControl () const

Protected Slots
void	clearWriteBuffer ()
void	flushWriteBuffer ()
void	onIdleTimeout ()
void	onPingTimeout ()
void	onProtocolStart ()
void	onReadyRead ()
virtual void	onTimeout ()
void	pong (bool emitReady=true)
Protected Slots inherited from ChessPlayer
virtual void	onCrashed ()
virtual void	onTimeout ()

Protected Member Functions
void	addOption (EngineOption *option)
void	addVariant (const QString &variant)
void	clearVariants ()
EngineOption *	getOption (const QString &name) const
int	id () const
virtual bool	isPondering () const
virtual void	parseLine (const QString &line)=0
bool	pondering () const
EngineConfiguration::RestartMode	restartMode () const
virtual bool	restartsBetweenGames () const
virtual void	sendOption (const QString &name, const QVariant &value)=0
virtual bool	sendPing ()=0
virtual void	sendQuit ()=0
virtual void	sendStop ()=0
virtual void	startGame ()=0
virtual void	startProtocol ()=0
bool	stopThinking ()
bool	whiteEvalPov () const
Protected Member Functions inherited from ChessPlayer
Chess::Board *	board ()
virtual bool	canPlayAfterTimeout () const
void	claimResult (const Chess::Result &result)
void	emitMove (const Chess::Move &move)
void	forfeit (Chess::Result::Type type, const QString &description=QString())
const ChessPlayer *	opponent () const
void	setError (const QString &error)
void	setState (State state)
virtual void	startThinking ()=0

Static Protected Member Functions
static QStringRef	firstToken (const QString &str, bool readToEnd=false)
static QStringRef	nextToken (const QStringRef &previous, bool readToEnd=false)

Additional Inherited Members
Signals inherited from ChessPlayer
void	debugMessage (const QString &data)
void	disconnected ()
void	moveMade (const Chess::Move &move)
void	nameChanged (const QString &name)
void	ready ()
void	resultClaim (const Chess::Result &result)
void	startedThinking (int timeLeft)
void	stoppedThinking ()
void	thinking (const MoveEvaluation &eval)
Protected Attributes inherited from ChessPlayer
MoveEvaluation	m_eval

Detailed Description

An artificial intelligence chess player.

ChessEngine is a separate process (run locally or over a network) using either the Xboard or Uci chess protocol. Communication between the GUI and the chess engines happens via a QIODevice.

See also

XboardEngine

UciEngine

Member Enumeration Documentation

WriteMode

enum ChessEngine::WriteMode

The write mode used by write() when the engine is being pinged. This doesn't affect the IO device's buffering.

Enumerator
Buffered	Use the write buffer.
Unbuffered	Bypass the write buffer.

Constructor & Destructor Documentation

ChessEngine()

ChessEngine::ChessEngine

(

QObject *

parent = nullptr

)

Creates and initializes a new ChessEngine.

Member Function Documentation

addOption()

void ChessEngine::addOption ( EngineOption *  option )

protected

Adds option to the engine options list.

addVariant()

void ChessEngine::addVariant ( const QString &  variant )

protected

Adds variant to the list of supported variants.

applyConfiguration()

void ChessEngine::applyConfiguration

(

const EngineConfiguration &

configuration

)

Applies configuration to the engine.

clearVariants()

void ChessEngine::clearVariants ( )

protected

Clears the list of supported variants.

clearWriteBuffer

void ChessEngine::clearWriteBuffer ( )

protectedslot

Clear the write buffer without flushing it.

device()

QIODevice * ChessEngine::device

(

)

const

Returns the current device associated with the engine.

endGame()

void ChessEngine::endGame ( const Chess::Result &  result )

virtual

Tells the player that the game ended by result.

Note

Subclasses that reimplement this function must call the base implementation.

Reimplemented from ChessPlayer.

Reimplemented in UciEngine, and XboardEngine.

firstToken()

QStringRef ChessEngine::firstToken ( const QString &  str, bool  readToEnd = false  )

staticprotected

Reads the first whitespace-delimited token from a string and returns a QStringRef reference to the token.

If readToEnd is true, the whole string is read, except for leading and trailing whitespace. Otherwise only one word is read.

If str doesn't contain any words, a null QStringRef object is returned.

flushWriteBuffer

void ChessEngine::flushWriteBuffer ( )

protectedslot

Flushes the write buffer. If there are any commands in the buffer, they will be sent to the engine.

getOption()

EngineOption * ChessEngine::getOption ( const QString &  name ) const

protected

Returns the option that matches name. Returns 0 if an option with that name doesn't exist.

id()

int ChessEngine::id ( ) const

protected

Gives id number of the engine

isHuman()

bool ChessEngine::isHuman ( ) const

virtual

Returns true if the player is human.

Implements ChessPlayer.

isPondering()

bool ChessEngine::isPondering ( ) const

protectedvirtual

Returns true if the engine is currently thinking on the opponent's move; otherwise returns false.

Reimplemented in UciEngine.

isReady()

bool ChessEngine::isReady ( ) const

virtual

Returns true if the player is ready for input.

Note

When the player's state is Disconnected, this function still returns true if all the cleanup following the disconnection is done.

Reimplemented from ChessPlayer.

nextToken()

QStringRef ChessEngine::nextToken ( const QStringRef &  previous, bool  readToEnd = false  )

staticprotected

Reads the first whitespace-delimited token after the token referenced by previous.

If readToEnd is true, everything from the first word after previous to the end of the string is read, except for leading and trailing whitespace. Otherwise only one word is read.

If previous is null or it's not followed by any words, a null QStringRef object is returned.

onIdleTimeout

void ChessEngine::onIdleTimeout ( )

protectedslot

Called when the engine idles for too long.

onPingTimeout

void ChessEngine::onPingTimeout ( )

protectedslot

Called when the engine doesn't respond to ping.

onProtocolStart

void ChessEngine::onProtocolStart ( )

protectedslot

Called when the engine has started the chess protocol and is ready to start a game.

onReadyRead

void ChessEngine::onReadyRead ( )

protectedslot

Reads input from the engine.

options()

QList< EngineOption * > ChessEngine::options

(

)

const

Returns a list of supported options and their values.

parseLine()

virtual void ChessEngine::parseLine ( const QString &  line )

protectedpure virtual

Parses a line of input from the engine.

Implemented in UciEngine, and XboardEngine.

ping()

void ChessEngine::ping

(

bool

sendCommand = true

)

Sends a ping message (an echo request) to the engine to check if it's still responding to input, and to synchronize it with the game operator. If the engine doesn't respond in reasonable time, it will be terminated.

if sendCommand is false, nothing is actually sent to the engine (but we'll pretend a message was sent); otherwise the ping message is sent.

Note

All input to the engine will be delayed until we get a response to the ping.

pondering()

bool ChessEngine::pondering ( ) const

protected

Returns true if pondering is enabled for the engine; otherwise returns false.

Note

Even if pondering is enabled, it's still possible that the engine does not support pondering.

pong

void ChessEngine::pong ( bool  emitReady = true )

protectedslot

Called when the engine responds to ping.

Does nothing if the engine is not being pinged. Flushes any pending output to the engine. If emitReady is true, the ready() signal is emitted after pending output is flushed.

protocol()

virtual QString ChessEngine::protocol ( ) const

pure virtual

Returns the engine's chess protocol.

Implemented in UciEngine, and XboardEngine.

restartMode()

EngineConfiguration::RestartMode ChessEngine::restartMode ( ) const

protected

Returns the restart mode. The default value is EngineConfiguration::RestartAuto.

restartsBetweenGames()

bool ChessEngine::restartsBetweenGames ( ) const

protectedvirtual

Returns true if the engine restarts between games; otherwise returns false.

Reimplemented in XboardEngine.

sendOption()

virtual void ChessEngine::sendOption ( const QString &  name, const QVariant &  value  )

protectedpure virtual

Tells the engine to set option name's value to value.

Implemented in UciEngine, and XboardEngine.

sendPing()

virtual bool ChessEngine::sendPing ( )

protectedpure virtual

Sends a ping command to the engine. Returns true if successful; otherwise returns false.

Implemented in UciEngine, and XboardEngine.

sendQuit()

virtual void ChessEngine::sendQuit ( )

protectedpure virtual

Sends the quit command to the engine.

Implemented in UciEngine, and XboardEngine.

sendStop()

virtual void ChessEngine::sendStop ( )

protectedpure virtual

Sends the stop command to the engine.

Implemented in UciEngine, and XboardEngine.

setDevice()

void ChessEngine::setDevice

(

QIODevice *

device

)

Sets the current device to device.

setOption()

void ChessEngine::setOption	(	const QString &	name,
		const QVariant &	value
	)

Sets an option with the name name to value.

Note

If the engine doesn't have an option called name, nothing happens.

start()

void ChessEngine::start

(

)

Starts communicating with the engine.

Note

The engine device must already be started.

startGame()

virtual void ChessEngine::startGame ( )

protectedpure virtual

Starts the chess game set up by newGame().

Implements ChessPlayer.

Implemented in UciEngine, and XboardEngine.

startProtocol()

virtual void ChessEngine::startProtocol ( )

protectedpure virtual

Puts the engine in the correct mode to start communicating with it, using the chosen chess protocol.

Implemented in UciEngine, and XboardEngine.

stopThinking()

bool ChessEngine::stopThinking ( )

protected

Tells the engine to stop thinking and move now (if on move).

Returns true if the stop message was actually sent; otherwise returns false.

supportsVariant()

bool ChessEngine::supportsVariant ( const QString &  variant ) const

virtual

Returns true if the player can play variant.

Implements ChessPlayer.

variants()

QStringList ChessEngine::variants

(

)

const

Returns a list of supported chess variants.

whiteEvalPov()

bool ChessEngine::whiteEvalPov ( ) const

protected

Are evaluation scores from white's point of view?

write()

void ChessEngine::write	(	const QString &	data,
		WriteMode	mode = Buffered
	)

Writes text data to the chess engine.

If mode is Unbuffered, the data will be written to the device immediately even if the engine is being pinged.

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The documentation for this class was generated from the following files:

• projects/lib/src/chessengine.h
• projects/lib/src/chessengine.cpp