Releasing Little Wing 0.5.0

After a few weeks of work and 8 months since the last release of Little Wing, a chess engine written in Rust, the new version 0.5.0 is ready!

Most of the gain in strength (around 40 ELO) comes from a faster move generator implementing hyperbola quintessence. But the two most important features are Android support and an improved command line interface (CLI).

Changelog

Added

Use Hyperbola Quintessence and First Rank Attacks for sliding piece attacks
Use Xorshift random number generator for Zobrist hashing
Add depth parameter to perft CLI command
Add save fen and save pgn CLI commands
Add --silent flag to executable

Changed

Improve CLI output
Rename load CLI command to load fen
Rename Direction to Shift and introduce a new (compass) Direction
Rename Move* to PieceMove*
Store castling rights in a u8 in Position
Use fail-soft instead of fail-hard in search
Refactor many parts of the code

Tournament results

Here are the latest results of gauntlet tournaments with 40 moves in 60+0.6 seconds:

Rank Name                         Elo    +    - games score oppo. draws
   1 Dorpsgek Dillinger 1        2244   13   13  2695   72%  2061   12% 
   2 RattateChess 1.0 Nosferatu  2200   12   12  2694   67%  2061   11% 
   3 Napoleon                    2101   12   12  2695   55%  2061   20% 
   4 Little Wing v0.5.0          2077    6    6 10548   54%  2044   14% 
   5 Cinnamon 2.0                2040   12   12  2690   47%  2061   18% 
   6 Little Wing v0.4.0          2033    8    8  6820   48%  2045   15% 
   7 Poor little Pinkus          1984   12   12  2693   40%  2061   13% 
   8 Sjaak II 1.4.1              1934   12   12  2694   34%  2061   16% 
   9 Sayuri 2018.05.23           1803   14   14  2695   20%  2061   10%

And with 40 moves in 10+0.1 seconds:

Rank Name                         Elo    +    - games score oppo. draws
   1 Dorpsgek Dillinger 1        2293    4    4 32751   75%  2086   11% 
   2 RattateChess 1.0 Nosferatu  2200    4    4 32747   64%  2086   11% 
   3 Napoleon                    2118    3    3 32747   54%  2086   17% 
   4 Little Wing v0.5.0          2096    3    3 49716   52%  2078   12% 
   5 Little Wing v0.4.0          2048    4    4 27439   46%  2078   13% 
   6 Sjaak II 1.4.1              1950    4    4 32738   33%  2086   13% 
   7 Sayuri 2018.05.23           1832    4    4 32743   21%  2086    9%

Links

Tags: news, littlewing, chess