8x8 Board

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8x8 Board [1]

The 8x8 Board as basic square-centric board representation is either a two-dimensional array of bytes (or integers), containing piece and empty square codes, indexed by file and rank index, or more commonly a one-dimensional array indexed by a square in a 0..63 range which combines rank or file indices in three consecutive bits each [2] . Such a board representation is often used redundantly in bitboard programs to answer the question which piece (if any) resides on a square efficiently. It has to deal with square mapping accordantly.


As a lone board representation, the 8x8 board has some efficiency issues with move generation related to off the board test. Therefore more common are approaches dealing with that, that is 10x12 board with surrounding ranks and files, and Vector Attacks with its cheap test and unique square difference property with respect to distance and direction [3]. In Games Playing with Computers, 1972 [4] , Alex Bell introduced an array of 65 squares, where the purpose of square 65 (always empty) is to detect pawns capturing outside the board by a table driven move generator.

See also

Square Mapping Considerations


Forum Posts

External Links

Cast [5]: Jean Arp, Paul Bowles, Ceal Bryson, Alexander Calder, Jean Cocteau, Willem de Vogel, Dorothea Tanning
Max Ernst, Richard Huelsenbeck, Frederick Kiesler, Julien Lary, Julien Levy, Jaqueline Matisse, Eugene Pellegrini, Man Ray, Yves Tanguy


  1. 8x8 Board with LERF square indices, captured with Bibob by Gerd Isenberg, 2012
  2. Chess board representations by Robert Hyatt
  3. Fritz Reul (2009). New Architectures in Computer Chess. Ph.D. Thesis, 2 Non-Bitboard Architectures
  4. Chapter 3: Board Games - 3.1 CHESS from Alex Bell (1972). Games Playing with Computers. Allen & Unwin, ISBN-13: 978-0080212227
  5. 8 X 8: A Chess Sonata in 8 Movements (1957) - Full Cast & Crew - IMDb

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