Module pleco::helper::prelude

Default functions for accessing the statically computed tables.

Safety

Using any of these methods is inherently unsafe, as it is not guaranteed that they'll be initiated correctly. Consider using the Helper structure to guarantee initialization.

Documentation

These functions are documented in Helper , rather than here.

Functions

adjacent_file	Gets the adjacent files BitBoard of the file
adjacent_sq_file	Gets the adjacent files BitBoard of the square
aligned	Returns if three Squares are in the same diagonal, file, or rank.
between_bb	Get the line (diagonal / file / rank) BitBoard between two squares, not including the squares, if it exists.
bishop_moves	Generate Bishop Moves BitBoard from a bishop square and all occupied squares on the board. This function will return captures to pieces on both sides. The resulting BitBoard must be AND'd with the inverse of the intending moving player's pieces.
distance_of_sqs	Get the distance of two squares.
forward_file_bb	Returns the BitBoard of all squares in the file in front of the given one.
forward_rank_bb	Returns the BitBoard of all squares in the rank in front of the given one.
init_statics	Initializes the static structures. Guarantees to only allow being called once.
king_moves	Generate King Moves BitBoard from a source square.
knight_moves	Generate Knight Moves BitBoard from a source square.
line_bb	Get the line (diagonal / file / rank) BitBoard that two squares both exist on, if it exists.
passed_pawn_mask	Returns a BitBoard allowing for testing of the a pawn being a "passed pawn".
pawn_attacks_from	Pawn attacks BitBoard from a given square, per player. Basically, given square x, returns the BitBoard of squares a pawn on x attacks.
pawn_attacks_span	Returns the BitBoard of all squares that can be attacked by a pawn of the same color when it moves along its file, starting from the given square. Basically, if the pawn progresses along the same file for the entire game, this bitboard would contain all possible forward squares it could attack
piece_value	Returns the value of a Piece. If eg is true, it returns the end game value. Otherwise, it'll return the midgame value.
piecetype_value	Returns the value of a PieceType. If eg is true, it returns the end game value. Otherwise, it'll return the midgame value.
psq	Returns the score for a player's piece being at a particular square.
queen_moves	Generate Queen Moves BitBoard from a bishop square and all occupied squares on the board. This function will return captures to pieces on both sides. The resulting BitBoard must be AND'd with the inverse of the intending moving player's pieces.
ring_distance	Returns the ring of bits surrounding the square sq at a specified distance.
rook_moves	Generate Rook Moves BitBoard from a bishop square and all occupied squares on the board. This function will return captures to pieces on both sides. The resulting BitBoard must be AND'd with the inverse of the intending moving player's pieces.
z_castle	Returns the Zobrish hash for a castling right.
z_ep	Returns the zobrist hash for a given zobrist square.
z_no_pawns	Returns the Zobrist Hash for having no pawns.
z_side	Returns the Zobrist Hash for having a Black Player's turn.
z_square	Returns the Zobrist hash for a given square, and player / piece at that square.