Summary
- The original suction window calculation, including thread variance and the previous optimism coefficient, was restored to stabilize the search.
- The re-search logic after a fail-low was reverted so that the upper bound is reduced directly to alpha before expanding the suction window.
Test
- make build
- bash tests/perft.sh src/revolution-dev_v2.40_130925
Once Chessmaster 5500 user and wrote its opening books for my use. Now play engines at Playchess
I remember that program. I played a game as a kid at El Corte Inglés against that program, which used a board at the time, and I lost with white against a Budapest player, due to nerves, because I remember having the advantage. I don’t know what length of the opening books in future editions of Chessmaster were used. But it was certainly a classic, and I think it reached 2300 real ratings in its early days. Hugs, and thank you for your kind words.