Welcome to!

This website is the home of the chess engine Andscacs.

Andscacs is a module for analysis and a game of chess UCI

It's born in September 2013. It has approximately 3240 elo.

The new versions will be published in this website.

Andscacs mean "And" for Andorra, the country where I live, and scacs for "escacs", chess in catalan.

Download last version    32 and 64 bits Windows and Linux (0.91, 9/mai/2017)

Rating lists.   CCRL - CEGT - IPON - FCP - FastGM

Changes, 9/may/2017

* Improved various evaluation parameters, pawn structure, knights, king safety.

* Reworked threats evaluation.

* Solved little bugs.

* Speed and move ordering improvements.

* Improved time management.

* Improvements in some endgames.

* Improvement of various imbalances.

* Solved bugs when playing at Infinitychess or Playchess.

0.91 (Windows and Linux)

Changes, 24/mar/2017

* Improved various evaluation parameters.

* Solved little bugs.

* Speed and move search improvements.

* Improved pawn hash.

0.90 (Windows and Linux)

Changes, 11/des/2016

* Improved various evaluation parameters, mainly about king safety.

* Solved little bugs.

* Speed improvements.

* Improved some endgames.

0.89 (Windows and Linux)

Changes, 28/oct/2016

* Improved various evaluation parameters.

* Add ability to treat heterodox positions.

* Add "Contempt" parameter to try to avoid draw.

* Solved little bugs.

* Speed improvements.

* Improved time management.

0.88 (Windows) 0.88 (Linux)

Canvis, 21/jul/2016

* Version that is playing at TCEC at stage 3.

* Improved various evaluation parameters.

* Solved little bugs.

* Improved pawn evaluation.

* Improvements on king safety.

* Speed improvements.

* Improved time management.

* Improved some endgames.

* Improved move sorting.

* Improved imbalances.


Changes, 19/jun/2016

* Improved various evaluation parameters.

* Improvements on king safety.

* Improved imbalances and space evaluation.

* Improved passed pawns.

* Improved some endgames.

* Improved lmr.

* Speed improvements.

* Solved little bugs.

* Tries to avoid to give draw too easily.

* Improved SMP scaling.

* Improved time management.

* Improved move sorting.


Changes, 14/jun/2016

* Version that is playing at TCEC at stage 2.


Changes, 26/mai/2016

* Version that is playing at TCEC at stage 1b.


Changes, 24/mar/2016

* Solved little bugs.

* Improved various evaluation parameters.

* Improvements on king safety.

* Improved lmr.

* Improved some endgames.

* Added uci option "AlwaysFullPv" to show more complete principal variation.

* Some small speed improvements.


Changes, 22/gen/2016

* Solved little bugs.

* Improved evaluation of knights.

* Improved evaluation of pawns.

* Improvements on king safety.

* Improvements on space evaluation.

* Improvements on opening phase.

* Some small speed improvements.

* Fixed ponder mode.


Changes, 7/des/2015

* Solved little bugs.

* Improved evaluation of pawns.

* Improved reductions.

* Some small speed improvements.

* Slight improvements on king safety.

* General reevaluation of most parameters.


Changes, 10/nov/2015

* Solved little bugs.

* Slight improvements on king safety.

* Improved prunes, null move and lmr.

* Improved main hash.

* Some small speed improvements.

* Improved evaluation of passed pawns.

* Improved evaluation of rooks, knights and bishops.

* Small improvements on multi processor mode.


Changes, 16/ago/2015

* Solved little bugs.

* Some small speed improvements.

* Improvements on multi processor mode.

* Improved razoring, null move and lmr.

* Don't evaluate king safety on some simple endgames.


Changes, 24/jun/2015

* Solved a bug when pondering on Chessbase and other interfaces.


Changes, 20/jun/2015

* Improved pawn, knight and bishop evaluation.

* Improvements on move ordering.

* Slight improvements on king safety.

* Slight compensation of material difference when big mobility difference.

* Small speed improvements.

* Little improvements on search of moves.

* Solved various bugs.


Changes, 17/abr/2015

* Added option to use various simultaneous threads of analysis to profit from the power of the CPU (multi-thread, SMP).

* Added option to analyze various alternatives simultaneously (multi pv).

* Now works Ponder mode.

* Little LMR improvements.

* Reduced a little more the worst moves at root.

* Small improvements on move ordering.

* Changed developing environment to Visual Studio 2013 Community.

* Added hash of refutation of 3 and 5 moves.

* Slight improvements on time management.

* Slight improvement on rook, knight and bishop evaluation, and king safety.

* Improvements in search function.

* Solved various bugs.


Changes, 1/feb/2015

* Little LMR improvements.

* Added knowledge and improvements to various endgames.

* Improvements on move ordering and speed.

* Improvement on capture extension.

* Little improvements on king safety.

* Improvements on time management.

* Solved various bugs.

* Improvement on rook evaluation.

* Countermoves.

* Double move refutation.

* Hash of all the pieces except king and pawns.


Changes, 17/des/2014

* Improved evaluation of passed pawns.

* General improvement of speed.

* Fixed some bugs.

* New king safety evaluation.

* Little improvements on LMR.

* Improved mobility values.

* Removed second hash of evaluations. Now uses only main hash for this.


Changes, 5/nov/2014

* Most parts of the engine are done again from scratch, with the objective of speed gain in critical points.

* ow uses 16 bits to store the moves, and 32 bits to store jointly the values of opening and endgame to not having to treat them separately.

* Now uses magic bitboards to speed the attack calculations.

* Detected some bugs that now are not in this new version.

* Separated the move generation in phases (hash, captures, non captures) instead of generating all in each iteration.

* Improved See adding x-ray.

* Now a move can be pruned because of See.


Changes, 7/jun/2014

* Some little speed optimizations and bug fixes.

* Move ordering: At move generation, duplicate value of exchanges of pieces, and increase values of passed pawns moving to ranks 6 or 7.

* Move generation: start at a1 for white pieces, and at h8 for black pieces.

* Cut more moves at the last alpha_beta before quiescence search.

* Penalization for trying to win without pawns.

* Added divide command for doing perft move by move.

* LMR in endgame: increase or decrease it depending on some conditions.

* Don't do LMR if it's a move of pawn to the rank 7.

* Optimized hash and solved a bug. Now it's saved also the evaluation of the position.

* Big optimization of king safety.

* If the evaluation of one iteration is 0, for the next one clean killers and history.

* If at the end of quiesce there was no move analyzed, return static evaluation instead of alpha.


Changes, 7/mai/2014

* Prune more moves instead of trying them in some cases.

* If LMR don’t works, also reduces a little in some cases.

* Trapped knight’s evaluation more aggressive.


Changes, 5/mai/2014

* Added knowledge of some basic endings, KRBKR, KRNKR, KRKN, KQBKQ, KQNKQ, KBNKR, KBBKR, KNNKR, KBPKB.

* Added some knowledge about endings with bishops of different color.

* Bonus for grouped passed pawns.

* Diminish the evaluation if it’s nearer the 50 move draw rule.

* Augmented velocity of move generation and doing the moves.

* Diminished the possibilities of hash key collision, and fixed the validation of the hash move.

* Optimized a case where it was possible to maintain a move in the hash even if there was none.

* Limited the maximum number of extensions possible before qsearch.

* Fixed bugs in move generation and about storing in history.

* Move ordering:

    •    Favor attacking moves in some cases.

    •    Little penalization for pieces than return to previous square.

    •    Little penalization for king moves when there are many pieces.

* Late Move Reductions, (LMR) :

    •    Reduce less if it’s an endgame.

    •    Reduce less if it’s in the firsts levels after root moves.

* Penalization for king too open.

* Moves found in hash than permit to return immediately, now are stored as killers and also update the history.

* Optimized the value about material ending that activates some reductions.


Changes, 10/abr/2014

* Improved some parameters of the evaluation function.

* Added knowledge of endgames KRPKR, KRKB, KBNK, KPK (Thanks to code of H.G. Muller

* Added knowledge of basic draw endgames.

* Increased speed of move generation.


Changes, 29/mar/2014

* Improved some parameters of the evaluation function.

* Improved values for Late Move Reduction.

* New king safety evaluation.


Changes, 3/mar/2014

* Added information of Nodes per second.

* Added Static Exchange Evaluation for quiet moves, for depth > 2.

* Some optimizations for speed gain.

* Better ordering of moves when the king is in check. Try first moving less valuable pieces and add history value of the move.

* Faster calculation of piece attacks. No need any further of rotated bitboards.

* Improved some parameters of the evaluation function.

* Improved values for Late Move Reduction. Principal cause of the elo gain of this version.

* Cut bad moves/captures in the theoretical last level before Quiesce, if Alpha is raised and there are a minimum of moves already verified.

* Penalty for advancing pawn that might be weak.

* Fixed bug on threat evaluation.

* Improved king safety evaluation.

* Little hash for evaluations.


Changes, 9/feb/2014

* Added version for 32 bit Windows, but it's 50 elo points weaker.

* It will not ask for msvcp100.dll if it is not installed on the computer.

* Minor changes on evaluation. Slightly stronger on very fast time controls.


Changes, 7/feb/2014

New version without a bug.


Changes, 6/feb/2014

1st version published.