#include <libchess/board/Bitboard.hpp>

Public Types
using	Integer = std::uint64_t

Public Member Functions
constexpr	Bitboard () noexcept=default
constexpr	Bitboard (Integer val) noexcept
constexpr auto	operator== (const Bitboard &) const noexcept -> bool=default
constexpr auto	to_int () const noexcept -> Integer
Observers
constexpr auto	any () const noexcept -> bool
constexpr auto	none () const noexcept -> bool
constexpr auto	count () const noexcept -> size_t
constexpr auto	test (const Square square) const noexcept -> bool
constexpr auto	test (BitboardIndex index) const noexcept -> bool
constexpr auto	first () const noexcept -> BitboardIndex
constexpr auto	last () const noexcept -> BitboardIndex
Modifiers
constexpr void	set (const Square square) noexcept
constexpr void	set (BitboardIndex index) noexcept
constexpr void	unset (const Square square) noexcept
constexpr void	unset (BitboardIndex index) noexcept
constexpr void	clear () noexcept
Iteration
constexpr auto	indices () const noexcept
constexpr auto	squares () const noexcept
constexpr auto	subboards () const noexcept
Binary operations
constexpr auto	inverse () const noexcept -> Bitboard
constexpr auto	operator&= (const Bitboard &other) noexcept -> Bitboard &
constexpr auto	operator\|= (const Bitboard &other) noexcept -> Bitboard &
constexpr auto	operator^= (const Bitboard &other) noexcept -> Bitboard &
constexpr auto	operator<<= (size_t num) noexcept -> Bitboard &
constexpr auto	operator>>= (size_t num) noexcept -> Bitboard &

Static Public Member Functions
static constexpr auto	from_square (Square square) noexcept -> Bitboard

Related Symbols
(Note that these are not member symbols.)
consteval auto	operator""_bb (const unsigned long long value) noexcept -> Bitboard

constexpr auto	operator& (const Bitboard &lhs, const Bitboard &rhs) noexcept -> Bitboard
constexpr auto	operator\| (const Bitboard &lhs, const Bitboard &rhs) noexcept -> Bitboard
constexpr auto	operator^ (const Bitboard &lhs, const Bitboard &rhs) noexcept -> Bitboard
constexpr auto	operator<< (const Bitboard &board, size_t num) noexcept -> Bitboard
constexpr auto	operator>> (const Bitboard &board, size_t num) noexcept -> Bitboard
auto	print_ascii (Bitboard board) -> std::string

Detailed Description

This class is similar to std::bitset, in that it is a simple collection of 64 bits, but it includes some convenience methods specific to usage as a bitboard.

Each bit represents a square of the chessboard; the bit is 1 if there is a piece there, and 0 if the square is empty.

Mapping ranks/files to indices of bits within a bitboard is handled by the Square class.

See also: Pieces, masks

Definition at line 48 of file Bitboard.hpp.

Member Typedef Documentation

◆ Integer

using chess::board::Bitboard::Integer = std::uint64_t

Unsigned integer type used for bitboard representation.

Definition at line 50 of file Bitboard.hpp.

Constructor & Destructor Documentation

◆ Bitboard() [1/2]

chess::board::Bitboard::Bitboard ( )

constexprdefaultnoexcept

Constructs an empty bitboard.

◆ Bitboard() [2/2]

chess::board::Bitboard::Bitboard ( Integer val )

explicitconstexprnoexcept

Constructs a bitboard from an integer representation.

See also: to_int()

Definition at line 274 of file Bitboard.hpp.

Member Function Documentation

◆ any()

auto chess::board::Bitboard::any ( ) const -> bool

inlinenodiscardconstexprnoexcept

Returns true if any of the bits are set.

Definition at line 67 of file Bitboard.hpp.

◆ clear()

void chess::board::Bitboard::clear ( )

inlineconstexprnoexcept

Resets all bits to 0.

Definition at line 117 of file Bitboard.hpp.

◆ count()

auto chess::board::Bitboard::count ( ) const -> size_t

inlinenodiscardconstexprnoexcept

Returns the number of bits that are set.

Definition at line 73 of file Bitboard.hpp.

◆ first()

auto chess::board::Bitboard::first ( ) const -> BitboardIndex

nodiscardconstexprnoexcept

Returns the index of the first set bit. This operation may also be known as "bitscan forward". Returns 64 if all bits are 0.

Definition at line 309 of file Bitboard.hpp.

◆ from_square()

auto chess::board::Bitboard::from_square ( Square square ) -> Bitboard

staticnodiscardconstexprnoexcept

Returns a bitboard with only a single bit set.

Definition at line 279 of file Bitboard.hpp.

◆ indices()

auto chess::board::Bitboard::indices ( ) const

nodiscardconstexprnoexcept

Returns an iterable range of indices representing the 1 bits in this bitboard. The returned indices should be iterated by value, not by reference; i.e.:

for (auto index : board.indices())

; // ...

chess::board

Definition Bitboard.hpp:33

See also: squares(), subboards()

Definition at line 452 of file Bitboard.hpp.

◆ inverse()

auto chess::board::Bitboard::inverse ( ) const -> Bitboard

nodiscardconstexprnoexcept

Returns a copy of this bitboard with all bits flipped (binary NOT).

Definition at line 357 of file Bitboard.hpp.

◆ last()

auto chess::board::Bitboard::last ( ) const -> BitboardIndex

nodiscardconstexprnoexcept

Returns the index of the last set bit. This operation may also be known as "bitscan reverse". Returns 64 if all bits are 0.

Definition at line 315 of file Bitboard.hpp.

◆ none()

auto chess::board::Bitboard::none ( ) const -> bool

inlinenodiscardconstexprnoexcept

Returns true if none of the bits are set.

Definition at line 70 of file Bitboard.hpp.

◆ operator&=()

auto chess::board::Bitboard::operator&= ( const Bitboard & other ) -> Bitboard &

constexprnoexcept

Performs binary AND with another bitboard.

Definition at line 327 of file Bitboard.hpp.

◆ operator<<=()

auto chess::board::Bitboard::operator<<= ( size_t num ) -> Bitboard &

constexprnoexcept

Performs binary shift left (towards higher index positions). Zeroes are shifted in, and bits that would go to an index out of range are dropped.

Definition at line 345 of file Bitboard.hpp.

◆ operator==()

auto chess::board::Bitboard::operator== ( const Bitboard & ) const -> bool=default

nodiscardconstexprdefaultnoexcept

Returns true if the two bitboards have all the same bits set.

◆ operator>>=()

auto chess::board::Bitboard::operator>>= ( size_t num ) -> Bitboard &

constexprnoexcept

Performs binary shift right (towards lower index positions). Zeroes are shifted in, and bits that would go to an index out of range are dropped.

Definition at line 351 of file Bitboard.hpp.

◆ operator^=()

auto chess::board::Bitboard::operator^= ( const Bitboard & other ) -> Bitboard &

constexprnoexcept

Performs binary XOR with another bitboard.

Definition at line 339 of file Bitboard.hpp.

◆ operator|=()

auto chess::board::Bitboard::operator|= ( const Bitboard & other ) -> Bitboard &

constexprnoexcept

Performs binary OR with another bitboard.

Definition at line 333 of file Bitboard.hpp.

◆ set() [1/2]

void chess::board::Bitboard::set ( BitboardIndex index )

constexprnoexcept

Sets the given square's bit to 1. This method asserts if the given index is greater than 63.

Definition at line 293 of file Bitboard.hpp.

◆ set() [2/2]

void chess::board::Bitboard::set ( const Square square )

inlineconstexprnoexcept

Sets the given square's bit to 1.

Definition at line 101 of file Bitboard.hpp.

◆ squares()

auto chess::board::Bitboard::squares ( ) const

nodiscardconstexprnoexcept

Returns an iterable range of Square objects representing the 1 bits in this bitboard. The Square objects should be iterated by value, not by reference; i.e.:

for (auto square : board.squares())

; // ...

See also: indices(), subboards()

Definition at line 461 of file Bitboard.hpp.

◆ subboards()

auto chess::board::Bitboard::subboards ( ) const

nodiscardconstexprnoexcept

Returns an iterable range of Bitboard objects that each have a single bit set, each representing the 1 bits in this bitboard. This is a transformation of a single bitboard with up to 64 bits set into a set of up to 64 bitboards each with a single bit set.

The Bitboard objects should be iterated by value, not by reference; i.e.:

for (auto subboard : board.subboards())

; // ...

See also: indices(), squares()

Definition at line 467 of file Bitboard.hpp.

◆ test() [1/2]

auto chess::board::Bitboard::test ( BitboardIndex index ) const -> bool

nodiscardconstexprnoexcept

Returns true if there is a piece on the given square. This method asserts if the given index is greater than 63.

Definition at line 284 of file Bitboard.hpp.

◆ test() [2/2]

auto chess::board::Bitboard::test ( const Square square ) const -> bool

inlinenodiscardconstexprnoexcept

Returns true if there is a piece on the given square.

Definition at line 76 of file Bitboard.hpp.

◆ to_int()

auto chess::board::Bitboard::to_int ( ) const -> Integer

inlinenodiscardconstexprnoexcept

Converts this bitboard to its integer representation.

Definition at line 122 of file Bitboard.hpp.

◆ unset() [1/2]

void chess::board::Bitboard::unset ( BitboardIndex index )

constexprnoexcept

Sets the given square's bit to 0. This method asserts if the given index is greater than 63.

Definition at line 300 of file Bitboard.hpp.

◆ unset() [2/2]

void chess::board::Bitboard::unset ( const Square square )

inlineconstexprnoexcept

Sets the given square's bit to 0.

Definition at line 109 of file Bitboard.hpp.

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

libchess/include/libchess/board/Bitboard.hpp

Public Types

Public Member Functions

Static Public Member Functions

Related Symbols

Detailed Description

Member Typedef Documentation

◆ Integer

Constructor & Destructor Documentation

◆ Bitboard() [1/2]

◆ Bitboard() [2/2]

Member Function Documentation

◆ any()

◆ clear()

◆ count()

◆ first()

◆ from_square()

◆ indices()

◆ inverse()

◆ last()

◆ none()

◆ operator&=()

◆ operator<<=()

◆ operator==()

◆ operator>>=()

◆ operator^=()

◆ operator|=()

◆ set() [1/2]

◆ set() [2/2]

◆ squares()

◆ subboards()

◆ test() [1/2]

◆ test() [2/2]

◆ to_int()

◆ unset() [1/2]

◆ unset() [2/2]