New version chess engine: Tcheran 3.0

 

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.

v.3.0:

Use hard and soft time limits in our time management strategy (~28 Elo STC, ~43 Elo LTC)

Store the board state as [PieceOccupancy; Pieces] and [ColorOccupancy; Colors] (~24 Elo)

Collect the principal variation during search (~18 Elo)

Use 3.3% of the remaining time as base rather than 5% (~9 Elo)

Skip losing captures in quiescence (~8 Elo)

Add aspiration windows (~5 Elo)

Return best_eval in quiescence (~5 Elo)

Fail soft on TT cuts (~2 Elo)

Prefer TT nodes with a higher depth (~2 Elo)

Don't do RFP or NMP in TT nodes (~0 Elo)

Misc

Clear PersistentState and Control on ucinewgame (fails SPRT at -9 Elo but is strictly more correct)

Allocate TT before the first search (gains +10 undoing the -9 from the time spent allocating after ucinewgame and before the first search)

Add prettier search output if being used interactively

Rename MoveProvider -> MovePicker for consistency with other engines

Improved debug output when MovePicker perft tests fail

Move search termination check and 'force stop' of search into TimeStrategy

Fix OOM-kills due to briefly allocating two transposition tables during ucinewgame

Remove git-version for setting UCI version dynamically during development

Tcheran 2.5 - results:

Opponent	Score	+-	Games
CorChess 20240724	0/4	-4	4 Games
Arasan 24.2.2	0/4	-4	4 Games
Catto 0.12.1	2/2	+2	2 Games
Mufasa 0.2.1	2/2	+2	2 Games
Aramis 1.3.0	1.5/2	+1	2 Games
Hedgehog 2.407	1.5/2	+1	2 Games
Floyd 0.9 JA	1/2	+0	2 Games
Trinket 3.5.0	0.5/2	-1	2 Games
Yuli GM Pro 16	0/2	-2	2 Games
Uralochka 3.41a JA	0/2	-2	2 Games
Stockfish 16.1	0/2	-2	2 Games
Smaug 2.2.1 JA	0/2	-2	2 Games
Spaghet MariNNara 1.0	0/2	-2	2 Games
Obsidian 13.0	0/2	-2	2 Games
Nalwald 19	0/2	-2	2 Games
Lizard 10.5	0/2	-2	2 Games
Stockfish 20240723	0/2	-2	2 Games
Knightx 4.1	0/2	-2	2 Games
HypnoS 140724	0/2	-2	2 Games
Yuliana 5.0	0/2	-2	2 Games
Critter 1.6a	0/2	-2	2 Games

 

Tcheran 3.0 download