Paul Wiereyn

Home * People * Paul Wiereyn

Paul H. Wiereyn, a Dutch chess problem composer and chess solving engine and GUI programmer. He is author of a free Sudoku program and the Windows GUI APwin for the chess problem solving programs Alybadix and Popeye.

=0x88= In his 1985 paper Inventive Problem Solving, Paul Wiereyn described 0x88 coordinates with nibbles for ranks and files inside a byte, and used such square differences (mod 256) as table-index to determine pinned pieces and discovered checks in his problem solving program: It is obvious to chess-players that a piece when pinned should not be allowed to move out of the direction in which it is pinned. Hence, as a preliminary, we calculate, in one byte, the difference between the coordinates of the piece about to be moved and one's own King, e.g.,

Rd5 - Kf5 <=> 45 - 65 = E0, hexadecimals and reduction modulo 256

being implied throughout.

The difference, E0 say, serves to enter a table T. The tabular value T[E0] so found, when zero, indicates non-collinearity (the pieces are not on the same rank, file or (co-)diagonal). If not zero, the value codes the direction of collinearity, i.e., the pinning direction. In our example the value T[E0] = F0, stands for due West.

=Selected Publications=
 * Paul Wiereyn (1985). Problem-Solving Ability Tested II. ICCA Journal, Vol. 8, No. 3
 * Paul Wiereyn (1985). Inventive Problem Solving. ICCA Journal, Vol. 8, No. 4
 * Paul Wiereyn (1997). Genius-3 Cooked Endgame Studies. ICCA Journal, Vol. 20, No. 3 » Chess Genius

=External Links=
 * apwin
 * Chess Composers: March 31st - Paul H. Wiereyn (31-03-1936) Dutch composer

=References= Up one level