THE COMPACT CHESSBOARD REPRESENTATION

This note addresses theoretical and practical aspects of an important issue in computer-chess programming - the problem of chessboard representation. There are two main approaches used by the majority of computer-chess programs: arrays and bitboards. However, after many years of research and experiments with the chess engine AXON and its parallel version ACHILLES, we would like to introduce an alternative chessboard representation CCR (Compact Chessboard Representation), which performs very well, both on 32-bit and 64-bit hardware platforms. We will try to portray critical advantages and disadvantages in the programming and utilization of both data structures.