From 758f9c9350abee36a5865ec701560db8ea62004d Mon Sep 17 00:00:00 2001 From: Joost VandeVondele Date: Sat, 3 Dec 2022 08:50:46 +0100 Subject: [PATCH] Stockfish 15.1 MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Official release version of Stockfish 15.1 Bench: 3467381 --- Today, we have the pleasure to announce Stockfish 15.1. As usual, downloads will be freely available at stockfishchess.org/download *Elo gain and competition results* With this release, version 5 of the NNUE neural net architecture has been introduced, and the training data has been extended to include Fischer random chess (FRC) positions. As a result, Elo gains are largest for FRC, reaching up to 50 Elo for doubly randomized FRC[1] (DFRC). More importantly, also for standard chess this release progressed and will win two times more game pairs than it loses[2] against Stockfish 15. Stockfish continues to win in a dominating way[3] all chess engine tournaments, including the TCEC Superfinal, Cup, FRC, DFRC, and Swiss as well as the CCC Bullet, Blitz, and Rapid events. *New evaluation* This release also introduces a new convention for the evaluation that is reported by search. An evaluation of +1 is now no longer tied to the value of one pawn, but to the likelihood of winning the game. With a +1 evaluation, Stockfish has now a 50% chance of winning the game against an equally strong opponent. This convention scales down evaluations a bit compared to Stockfish 15 and allows for consistent evaluations in the future. *ChessBase settlement* In this release period, the Stockfish team has successfully enforced its GPL license against ChessBase. This has been an intense process that included filing a lawsuit[4], a court hearing[5], and finally negotiating a settlement[6] that established that ChessBase infringed on the license by not distributing the Stockfish derivatives Fat Fritz 2 and Houdini 6 as free software, and that ensures ChessBase will respect the Free Software principles in the future. This settlement has been covered by major chess sites (see e.g. lichess.org[7] and chess.com[8]), and we are proud that it has been hailed as a ‘historic violation settlement[9]’ by the Software Freedom Conservancy. *Thank you* The Stockfish project builds on a thriving community of enthusiasts (thanks everybody!) that contribute their expertise, time, and resources to build a free and open-source chess engine that is robust, widely available, and very strong. We invite our chess fans to join the fishtest testing framework and programmers to contribute to the project[10]. The Stockfish team [1] https://tests.stockfishchess.org/tests/view/638a6170d2b9c924c4c62cb4 [2] https://tests.stockfishchess.org/tests/view/638a4dd7d2b9c924c4c6297b [3] https://en.wikipedia.org/wiki/Stockfish_(chess)#Competition_results [4] https://stockfishchess.org/blog/2021/our-lawsuit-against-chessbase/ [5] https://stockfishchess.org/blog/2022/public-court-hearing-soon/ [6] https://stockfishchess.org/blog/2022/chessbase-stockfish-agreement/ [7] https://lichess.org/blog/Y3u1mRAAACIApBVn/settlement-reached-in-stockfish-v-chessbase [8] https://www.chess.com/news/view/chessbase-stockfish-reach-settlement [9] https://sfconservancy.org/news/2022/nov/28/sfc-named-trusted-party-in-gpl-case/ [10] https://stockfishchess.org/get-involved/ --- src/misc.cpp | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/misc.cpp b/src/misc.cpp index c7fa0e9a..2d86969f 100644 --- a/src/misc.cpp +++ b/src/misc.cpp @@ -68,7 +68,7 @@ namespace Stockfish { namespace { /// Version number or dev. -const string version = "dev"; +const string version = "15.1"; /// Our fancy logging facility. The trick here is to replace cin.rdbuf() and /// cout.rdbuf() with two Tie objects that tie cin and cout to a file stream. We -- 2.39.2