Piece attack tables. More...

#include <bitboard-attacks.h>

Static Public Member Functions
static SquareSet	getPawnAttackMask (Square sq, Color pawnColor) noexcept
	Returns a set of squares that a pawn can attack.

static SquareSet	getPawnAttackerMask (Square sq, Color pawnColor) noexcept
	Returns a set of squares from which a pawn can attack.

template<Color pawnColor, bool captureToRight>
static constexpr SquareSet	getPawnAttackersMask (SquareSet capturable) noexcept
	For a given set of squares, returns the squares where pawns can attack the given squares.

static SquareSet	getKnightAttackMask (Square sq) noexcept
	Returns the set of squares a knight can attack.

static SquareSet	getBishopAttackMask (Square sq, SquareSet occupancyMask) noexcept
	Returns the set of squares a bishop can attack, given also a set of occupied squares on board.

static SquareSet	getRookAttackMask (Square sq, SquareSet occupancyMask) noexcept
	Returns the set of squares a rook can attack, given also a set of occupied squares on board.

static SquareSet	getQueenAttackMask (Square sq, SquareSet occupancyMask) noexcept

static SquareSet	getKingAttackMask (Square sq) noexcept
	Returns the set of squares a king can attack.

static bool	pinCheck (Square src, SquareSet dstBit, Square kingSq, SquareSet pinnedPieces) noexcept
	Checks whether a move by a possibly pinned piece does not expose a check.

static SquareSet	determineAttackers (const SquareSet occupancyMask, const SquareSet turnColorMask, const SquareSet pawns, const SquareSet knights, const SquareSet bishops, const SquareSet rooks, const SquareSet kings, const Square sq, const Color turn) noexcept

static void	determineCheckersAndPins (SquareSet occupancyMask, SquareSet turnColorMask, SquareSet pawns, SquareSet knights, SquareSet bishops, SquareSet rooks, Square epSquare, SquareSet epCapturable, Square kingSq, Color turn, SquareSet &out_checkers, SquareSet &out_pinnedPieces) noexcept
	Determines all checkers and pinners.

static SquareSet	determineAttackedSquares (SquareSet occupancyMask, SquareSet pawns, SquareSet knights, SquareSet bishops, SquareSet rooks, Square king, Color turn) noexcept
	Determines all attacked squares.

Detailed Description

Piece attack tables.

Member Function Documentation

◆ determineAttackedSquares()

static SquareSet hoover_chess_utils::pgn_reader::Attacks::determineAttackedSquares	(	SquareSet	occupancyMask,
		SquareSet	pawns,
		SquareSet	knights,
		SquareSet	bishops,
		SquareSet	rooks,
		Square	king,
		Color	turn
	)

inlinestaticnoexcept

Determines all attacked squares.

Parameters

[in]	occupancyMask	All occupied squares. These block slider attacks
[in]	pawns	Attacking pawns
[in]	knights	Attacking knights
[in]	bishops	Attacking bishops and queens
[in]	rooks	Attacking rooks and queens
[in]	king	Attacking king
[in]	turn	Side to move (determines pawn attacking direction)

Returns: All attacked squares

◆ determineAttackers()

static SquareSet hoover_chess_utils::pgn_reader::Attacks::determineAttackers	(	const SquareSet	occupancyMask,
		const SquareSet	turnColorMask,
		const SquareSet	pawns,
		const SquareSet	knights,
		const SquareSet	bishops,
		const SquareSet	rooks,
		const SquareSet	kings,
		const Square	sq,
		const Color	turn
	)

inlinestaticnoexcept

◆ determineCheckersAndPins()

static void hoover_chess_utils::pgn_reader::Attacks::determineCheckersAndPins	(	SquareSet	occupancyMask,
		SquareSet	turnColorMask,
		SquareSet	pawns,
		SquareSet	knights,
		SquareSet	bishops,
		SquareSet	rooks,
		Square	epSquare,
		SquareSet	epCapturable,
		Square	kingSq,
		Color	turn,
		SquareSet &	out_checkers,
		SquareSet &	out_pinnedPieces
	)

inlinestaticnoexcept

Determines all checkers and pinners.

Parameters

[in]	occupancyMask	All occupied squares. These block slider attacks
[in]	turnColorMask	Pieces of the side to move
[in]	pawns	All pawns
[in]	knights	All knights
[in]	bishops	All bishops and queens
[in]	rooks	All rooks and queens
[in]	epSquare	En passant square or `Square::NONE`
[in]	epCapturable	En passant capturable pawn or `SquareSet::none()`
[in]	kingSq	King of side to move
[in]	turn	Side to move
[out]	out_checkers	Set of checking pieces
[out]	out_pinnedPieces	Set of pinned pieces. The capturable en passant pawn is included if it is pinned diagonally.

Remarks: A diagonally pinned en passant capturable pawn cannot be captured due to the pin.

◆ getBishopAttackMask()

static SquareSet hoover_chess_utils::pgn_reader::Attacks::getBishopAttackMask	(	Square	sq,
		SquareSet	occupancyMask
	)

inlinestaticnoexcept

Returns the set of squares a bishop can attack, given also a set of occupied squares on board.

Parameters

[in]	sq	Bishop square
[in]	occupancyMask	Set of occupied squares

Returns: Set of attacked squares

Per every diagonal direction from sq, the set of attacked squares is all squares between sq and the first occupied square (if any) including the occupied square. If no occupied squares are in that direction, then all squares in that direction are included.

Occupancy of sq is ignored.

The implementation used is as follows:

Build condition	Description
HAVE_X86_BMI2	Implementation using `Attacks_BMI2::getBishopAttackMask()`
Otherwise	Implementation using `Attacks_Portable::getBishopAttackMask()`

Example

o

B
	o

	o	o
			o

◆ getKingAttackMask()

static SquareSet hoover_chess_utils::pgn_reader::Attacks::getKingAttackMask ( Square sq )

inlinestaticnoexcept

Returns the set of squares a king can attack.

Parameters

[in] sq King square

Returns: Set of attacked squares




			K

◆ getKnightAttackMask()

static SquareSet hoover_chess_utils::pgn_reader::Attacks::getKnightAttackMask ( Square sq )

inlinestaticnoexcept

Returns the set of squares a knight can attack.

Parameters

[in] sq Knight square

Returns: Set of attacked squares

Example




			N

◆ getPawnAttackerMask()

static SquareSet hoover_chess_utils::pgn_reader::Attacks::getPawnAttackerMask	(	Square	sq,
		Color	pawnColor
	)

inlinestaticnoexcept

Returns a set of squares from which a pawn can attack.

Parameters

[in]	sq	Attacked square
[in]	pawnColor	Color of the attacking pawn

Returns: Set of squares from which a pawn can attack sq

Example



	sq
wP		wP

Remarks: Validity of pawn position is not assumed. Hence, attacker squares are provided for white pawns on 2nd rank (pawns on 1st) and black pawns on 7th rank (pawns on 8th).

◆ getPawnAttackersMask()

template<Color pawnColor, bool captureToRight>

static constexpr SquareSet hoover_chess_utils::pgn_reader::Attacks::getPawnAttackersMask ( SquareSet capturable )

inlinestaticconstexprnoexcept

For a given set of squares, returns the squares where pawns can attack the given squares.

Template Parameters

pawnColor	Color of the attacking pawns
captureToRight	Whether pawns are capturing towards right (increasing column number)

Parameters

[in] capturable Capturable squares. Typically all opponent's pawns and pieces

Returns: Set of pawn attacker squares

Example (white pawn, capture right)

c		c	c	c			c
c	c	c	wP	c	c	wP
wP	wP	c	wP	wP			c
			c	c		c
	c	wP	wP		wP
wP

Remarks: Validity of pawn position is not assumed. Hence, attacker squares are provided for white pawns on 2nd rank (pawns on 1st) and black pawns on 7th rank (pawns on 8th).

See also: generateMovesForPawnsTempl()

◆ getPawnAttackMask()

static SquareSet hoover_chess_utils::pgn_reader::Attacks::getPawnAttackMask	(	Square	sq,
		Color	pawnColor
	)

inlinestaticnoexcept

Returns a set of squares that a pawn can attack.

Parameters

[in]	sq	Pawn square
[in]	pawnColor	Color of the pawn

Returns: Set of squares the pawn can attack

Example





		wP

Remarks: Validity of pawn position is not assumed. Hence, attack squares are provided for white pawns on 1st rank and black pawns on 8th rank.

◆ getQueenAttackMask()

static SquareSet hoover_chess_utils::pgn_reader::Attacks::getQueenAttackMask	(	Square	sq,
		SquareSet	occupancyMask
	)

inlinestaticnoexcept

◆ getRookAttackMask()

static SquareSet hoover_chess_utils::pgn_reader::Attacks::getRookAttackMask	(	Square	sq,
		SquareSet	occupancyMask
	)

inlinestaticnoexcept

Returns the set of squares a rook can attack, given also a set of occupied squares on board.

Parameters

[in]	sq	Rook square
[in]	occupancyMask	Set of occupied squares

Returns: Set of attacked squares

Per horizontal/vertical direction from sq, the set of attacked squares is all squares between sq and the first occupied square (if any) including the occupied square. If no occupied squares are in that direction, then all squares in that direction are included.

Occupancy of sq is ignored.

The implementation used is as follows:

Build condition	Description
HAVE_X86_BMI2	Implementation using `Attacks_BMI2::getRookAttackMask()`
Otherwise	Implementation using `Attacks_Portable::getRookAttackMask()`

Example


	o

	R		o	o


o		o

◆ pinCheck()

static bool hoover_chess_utils::pgn_reader::Attacks::pinCheck	(	Square	src,
		SquareSet	dstBit,
		Square	kingSq,
		SquareSet	pinnedPieces
	)

inlinestaticnoexcept

Checks whether a move by a possibly pinned piece does not expose a check.

Parameters

[in]	src	Source square
[in]	dstBit	Destination square bit
[in]	kingSq	King square
[in]	pinnedPieces	Set of pinned pieces

Returns: Move legality (from the point of pin)

In case the piece on src is not pinned, this function will always return true.

In case the piece on src is pinned, this function checks whether the piece moves directly towards or away from the king.

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

pgn-reader/src/bitboard-attacks.h

Static Public Member Functions

Detailed Description

Member Function Documentation

◆ determineAttackedSquares()

◆ determineAttackers()

◆ determineCheckersAndPins()

◆ getBishopAttackMask()

◆ getKingAttackMask()

◆ getKnightAttackMask()

◆ getPawnAttackerMask()

◆ getPawnAttackersMask()

◆ getPawnAttackMask()

◆ getQueenAttackMask()

◆ getRookAttackMask()

◆ pinCheck()