Download :
http://dl.dropboxusercontent.com/u/89684995/texel106.7zThis version contains the following features:
- Support for polyglot opening books.
- A tool to automatically compute an opening book.
- An automatically computed polyglot opening book.
- Corrected handling of the 50 move draw rule and the halfmove clock when using tablebases.
- Source code for tools and automatic tests included.
The following executables are included in the download package:
texel64.exe : For 64-bit Windows 7 or later Intel systems with SSE42 and POPCOUNT.
texel64amd.exe : For 64-bit Windows systems with SSE42 and POPCOUNT.
texel64old.exe : For 64-bit Windows systems without SSE42 and POPCOUNT.
texel64 : For 64-bit Linux Intel systems with SSE42 and POPCOUNT.
texel-arm64 : For the Android armv8-a 64-bit architecture.
texel-arm : For the Android armv7-a architecture.
texel32.exe : For 32-bit Windows systems with SSE42 and POPCOUNT.
texel32old.exe : For 32-bit Windows systems without SSE42 and POPCOUNT.
For more Android executables see the "Texel Chess Engine" app in the Google Play Store.
The Linux executable requires a fairly recent 64-bit Linux distribution to run. To compile your own Linux version see the readme.txt file.
Texel 1.06 is around 40-50 elo stronger than Texel 1.05 in self play at very fast time controls.
Detailed list of changes:
Search:
- Don't use ply-2 killers for move ordering.
- Be more restrictive when extending losing (SEE<0) checks.
- Don't do check extensions for moves that are reduced by LMR.
- Don't do singular extensions if the unextended score is a mate score.
- Don't do LMR for the first 2 pseudo-legal moves.
- More aggressive LMR.
- More aggressive null move searches.
- Don't resolve a known loss score bound if there are other moves that are potentially not losing.
Parallel search:
- Allow a helper thread that fails high to interrupt the master thread.
- Changed MIN_SPLIT_DEPTH from 10 to 7 to make better use of multiple threads in short time control games.
- Changed maximum number of search threads to 512.
- Added support for windows NUMA systems having more than 64 cores.
Evaluation:
- Evaluation term to encourage "pawn breaks".
- Bonus for "latent" pawn attacks on enemy minor and major pieces.
- Bonus for safe queen contact checks.
- Only treat pawns on rank 2 and 3 as backwards pawns.
- King safety bonus for pieces (except bishops) on the same side of the board as the king.
- Parameter tuning.
Endgame:
- More patterns for fortress detection in bishop endings.
- On-demand tablebase generation for 4-men pawn-less positions.
- Knowledge about KRKBNN endgame, which is generally a draw.
- Better evaluation of KRBNKRB endgame.
- Larger evaluation score in KRRMKRR endgames
- Improved 50 move draw handling for TB probes.
Speed:
- Reduced TB probe overhead.
- Implemented a small (512KB) per-thread evaluation hash table.
- Removed support for fractional depth.
- Made the transposition table 4-way set associative.
Other:
- Removed "64-bit" from the engine name. 64 bit is now considered standard.
- UCI option to disable null moves.
- Made "BufferTime" a UCI parameter to control time handling safety margin.
- Don't start a new search iteration if it is unlikely that it can finish before the allocated thinking time is up.
- In analysis mode, don't age transposition table entries when starting a new search.
