Lozza 1.15

Fruit 2.1 piece and passed-pawn PSTs, typed arrays and a raft of V8-friendly speedups. Re-uploaded on 28 Apr 2015 with a move-ordering fix as build 6771 (this file).

Changes

• Fix move rank overflow.
• Don't use a/b tt if PV.
• add SQ* constants.
• change futility to 50.
• increase history range.
• Add R|Q on 7th bonus.
• Change futility to 60.
• Change queen to 1000.
• Jiggle what is and isn't predicated on mate scores.
• Add # to PV if mate score.
• Fix queening SAN format.
• Dump arbitrary passed bonuses.
• Dump Connectivity PSTs. They were making passed pawns stop.
• Use a passed pawn PST based on Fruit curve.
• Change PVS condition to !bestMove from numLegalMoves == 1.
• Use Fruit 2.1 piece PSTs.
• Add && !betaMate to futility condition.
• Don't do root Q futility.
• Change double time from 5 to 3 moves after opening.
• Fix +inc time control.
• Add some typed arrays to help V8.
• Tweaks to stop some V8 deoptimising.
• Don't call eval if in check in alphabeta().
• Speed up Q move gen.
• Speed up move gen.
• Speed up mobility;
• Speed up isAttacked();

Rating

CCRL 40/40: 2315

Usage

Use lozza.js with Node.js in any UCI chess GUI (Arena, Cute Chess, etc.), or in a web page/web worker.

Binaries

While Lozza is intended for web use, I can supply binaries on request. Please email me op12no2@gmail.com noting the target platform; thanks.