Tcheran 6.0 - new version chess engine

 

Tcheran - UCI chess engine  Author: Jonathan Gilchrist

Rating Chess Engines Diary CEDR=2242

If you want to know what the ranking of the Tcheran engine is, we encourage you to visit the website with the monthly updated CEDR ranking - RATING page.

Tcheran 6.0 what's new?

Unreleased

Skip bad captures in quiescence search (43.07 +- 13.42)

Misc

Fix TT mate scores being stored without root/position correction

6.0

Switched to NNUE-based evaluation with a (768->256)x2->1 net (223.69 +- 33.98)

Update NNUE features in a single loop when moving a single piece (10.65 +- 6.23)

Use align(64) for network weights (5.51 +- 4.06)

Encode double pushes in Move instead of checking in make_move (7.46 +- 6.47 in regression)

Misc

Make the engine both a library and binary to allow splitting functionality out

Split the texel tuner out of the main engine into its own tools/tuner project

Add tools/datagen for data generation

Add a full set of bench positions for 'bench' command

When in a tablebase position, report the tablebase PV line

Don't panic when SyzygyPath is set but is empty

Rewrite the FEN and UCI parsers without using nom (and remove nom as a dependency)

Remove the dependency on colored

Remove the runtime dependency on rand by pre-computing Zobrist components

Remove the Zobrist component for 'no en-passant target'

Give better error messages if we encounter panics in search code

Use Rust 1.85 and Edition 2024

Add initial bench

Removed accidental eval tracing from datagen, resulting in a 1.5x speedup

Remove the texel tuning code entirely in preparation for NNUE This also resolves a bug where the engine was always tracing its evaluation when running with cargo run due to the tuner feature being automatically enabled, as the 'engine' bin is a sibling of the 'engine' lib and cannot control its enabled features.

Author test:

Elo   | 216.74 +- 10.39 (95%)

Conf  | 8.0+0.08s Threads=1 Hash=16MB

Games | N: 4108 W: 2767 L: 492 D: 849

Penta | [14, 92, 454, 593, 901]

Elo   | 206.59 +- 20.48 (95%)

Conf  | 40.0+0.40s Threads=1 Hash=128MB

Games | N: 1024 W: 658 L: 112 D: 254

Penta | [6, 22, 110, 168, 206]

Tcheran 5.1 vs other engines:

Fortuna 1.0 JA	4/4	+4	4 Partii
Aurora 20241007	2.5/4	+1	4 Partii
JudaS ++ 5.0	1/4	-2	4 Partii
ShashChess 38	0/4	-4	4 Partii
Alexander 4.0	0/4	-4	4 Partii
DarkSeid 5.2	0/4	-4	4 Partii
Artemis 6TR	0/4	-4	4 Partii
Lambergar 1.0	0/4	-4	4 Partii
Halcyon 1	2/3	+1	3 Partii
Chessplusplus 1.2.0	2/3	+1	3 Partii
Belette 3.0.0	0.5/3	-2	3 Partii
Zeta-Dva 0402 JA	2/2	+2	2 Partii
Albatros 1.0.0	2/2	+2	2 Partii
MadChess 3.2.2	2/2	+2	2 Partii
Zagreus 5.0	2/2	+2	2 Partii
Dinora 0.3.0	2/2	+2	2 Partii
Omelette 1.0 JA	2/2	+2	2 Partii
Camel 1.6.0	2/2	+2	2 Partii
StoneChess 2024-09-13	2/2	+2	2 Partii
Amy 0.9.6-pre AB JA	2/2	+2	2 Partii
Ssehc 1.0	2/2	+2	2 Partii

 

Tcheran 6.0 download

Sample batch of this engine:

[Event "2024.09.14.NewEnginesTest"] [Site "Chess Engines Diary"] [Date "2024.09.17"] [Round "1.32"] [White "Tcheran 3.0"] [Black "StoneChess 2024-09-13"] [Result "1-0"] [ECO "B00"] [PlyCount "72"] [EventDate "2024.??.??"] {[%evp 0,72,19,31,42,25,25,33,56,29,66,76,56,24,36,21,11,4,-5,-3,16,4,10,-56,-5,-36,-18,-61,-61,-18,-15,-1,7,3,-6,-10,5,-13,9,3,10,13,10,49,46,43,67,31,56,45,49,47,71,43,90,58,61,73,114,133,184,186,153,187,235,243,654,652,873,1006,2044,2497,29979,29984,29985]} 1. e4 Nc6 2. d4 d5 3. e5 f6 4. Nf3 g5 5. h3 Bg7 6. Bb5 Nh6 7. O-O O-O 8. Re1 g4 9. hxg4 Bxg4 10. Bxc6 bxc6 11. e6 Qd6 12. Qe2 Nf5 13. c3 c5 14. Qc2 Bxf3 15. dxc5 Qc6 16. Qxf5 Be4 17. Qh3 Qxc5 18. Be3 Qb5 19. Nd2 Bg6 20. b3 Qd3 21. Nf3 c6 22. Rac1 Qa6 23. a4 Rfb8 24. Nd4 Rb7 25. b4 Rc8 26. a5 c5 27. bxc5 Rxc5 28. Nb3 Rcb5 29. Nc5 Qxa5 30. Nxb7 Rxb7 31. Red1 Rc7 32. Qf3 Be4 33. Qxe4 Rxc3 34. Qb1 Rxc1 35. Qb8+ Bf8 36. Rxc1 h5 1-0