NAMES OF CHESS PIECES CODE
NAMES OF CHESS PIECES PLUS

But if we like to index (zero based) arrays in C, C++ or Java by piece codes an offset has to be considered - also the Two's Complement needs abs-functions or additional indirection to extract the pure piece code, rather than to mask (and eventually shift) three bits. One approach is to use negative values for black and positive for white (or color don't care) pieces. Often the order of enumeration is conform with the value of the pieces, for instance a C++ enumeration: This way piece-type completely specifies the mechanical move abilities, and three bits are still appropriate for a dense range to index tables or lookup-arrays, e.g. Harm Geert Muller proposed distinct white and black pawn codes inside the otherwise colorless range of piece-types, to take the different move-directions of pawns into account. Īny enumeration of piece-type codes is fine. Another piece-array contained the associated piece-types or zero if the piece is missing. Beside a bitboard board-definition using 12 piece bitboards and occupancy as union set, Lachex used a redundant 8x8 board array, containing those 1.32 piece-codes, but zero for empty squares. Lachex for instance used following enumeration scheme: the a1-rook was labeled with 1, b1-knight with 2, a2-pawn with 9, the a8-rook with 17 and the h7-pawn with 32.

NAMES OF CHESS PIECES CODE

Other programs distinguish not only piece-type and color, but enumerate all 32 pieces from their initial position, which label or code does not change during the course of a game (even after a possible promotion of a pawn) and might be one-to-one associated with the bit-position of a 32-bit piece set, and/or are used to index a piece list containing the current square the piece resides on.

NAMES OF CHESS PIECES PLUS

Quite common is to use three bits to encode the piece-type plus one bit or Two's Complement (not recommend for languages with zero based array indices, like C, C++ or Java) for the color. Depending on the board representation, some programmers introduce an artificial blocking piece, which surrounds the embedded 8x8 boards inside a 10x12 board for cheaper off the board tests in offset move generation.įor cheaper extraction, most programmers prefer distinct coding of piece-types and the color of piece. Since only one piece may occupy one square at a time, one usually expands the range of piece codes with the Nil-Piece aka empty square, often encoded as zero. There are six types of pieces for each side, in total twelve different men.

Names of chess pieces