Big Search Progress!

What's Changed

New Original Search Stuff

• Post LMR History Reduction by @ProgramciDusunur in #323
• New experiment successfull with one shot! Add Corrplexity Extension by @ProgramciDusunur in #363
• TT was pv and fails high then do RFP by @ProgramciDusunur in #341

Search

• Better Improving Decision by @ProgramciDusunur in #316
• Add Node TM by @ProgramciDusunur in #321
• Add LMR Depth To Quiet History Pruning by @ProgramciDusunur in #324
• Add Promotion Move Ordering by @ProgramciDusunur in #336
• Add 50 Move Rule by @ProgramciDusunur in #364
• Add 50 Move Rule Scaling by @ProgramciDusunur in #366
• Tweak lmr depth with move history by @ProgramciDusunur in #337
• Add Major Correction History by @ProgramciDusunur in #338
• Don't create major correction history key from scratch by @ProgramciDusunur in #339
• Add Pawn History by @ProgramciDusunur in #351
• Shrink Pawn History by @ProgramciDusunur in #352
• Shrink histories to int16 by @ProgramciDusunur in #354
• Do more correction history by @ProgramciDusunur in #356
• Skip verification if null move score is much above beta by @ProgramciDusunur in #357
• New experiment successfull with one shot! Add Corrplexity Extension by @ProgramciDusunur in #363

Late Move Reductions

• Reduce The Minimum Number Of Moves That Must Be Searched For LMR by @ProgramciDusunur in #313
• TT PV Fail Low LMR by @ProgramciDusunur in #322
• Post LMR Shallower by @ProgramciDusunur in #329
• Try More Cut Node LMR by @ProgramciDusunur in #330
• if our tt was pv and we are improving then reduce less by @ProgramciDusunur in #367
• Reduce even less if our current node is principle variation node by @ProgramciDusunur in #359
• Add TT Capture LMR by @ProgramciDusunur in #361

Singular Extensions

• Depth 6 Singular Extensions by @ProgramciDusunur in #312
• Depth 5 Singular extensions by @ProgramciDusunur in #318
• Cut Node Extension And Double Negative Extension Based Cut Node Prediction by @ProgramciDusunur in #314
• Limit Singular Extensions by @ProgramciDusunur in #335
• Tweak SE beta with a depth formula by @ProgramciDusunur in #325
• Simplify Triple Negative Extension by @ProgramciDusunur in #348
• Simplify Some Extension Conditions by @ProgramciDusunur in #340
• Remove multicut by @ProgramciDusunur in #360

Reverse Futility Pruning

• If TT was pv then don't RFP by @ProgramciDusunur in #320
• TT was pv and fails high then do RFP by @ProgramciDusunur in #341
• More Aggressive RFP by @ProgramciDusunur in #345
• Depth 9 RFP by @ProgramciDusunur in #346
• Depth 11 RFP by @ProgramciDusunur in #358
• Add Corrplexity RFP by @ProgramciDusunur in #353
• Tweak RFP tt was pv decision by @ProgramciDusunur in #349

Late Move Pruning

• Add Improving in LMP by @ProgramciDusunur in #319

Transposition Table

• New TT Replacement Scheme by @ProgramciDusunur in #326
• A Tweak For TT Replacement by @ProgramciDusunur in #327
• TT Replacement TT PV Tweak by @ProgramciDusunur in #328
• Tweak TT Replacement with a offset by @ProgramciDusunur in #334

Evaluation

• Pieces threat king territory by @ProgramciDusunur in #343
• Add heavy king threats evaluation by @ProgramciDusunur in #344

Fix

• A Few Adjustments And Cleaning by @ProgramciDusunur in #310
• A Few Adjustments For Readability by @ProgramciDusunur in #311
• fix build failing to compile due to missing libs by @ProgramciDusunur in #317
• Fix Darwin problems by @ProgramciDusunur in #365

Strength

// 3.0.0 vs 2.0.0
Elo   | 102.92 +- 10.39 (95%)
Conf  | 8.0+0.08s Threads=1 Hash=32MB
Games | N: 2008 W: 776 L: 198 D: 1034
Penta | [10, 90, 361, 398, 145]

Elo   | 130.94 +- 15.27 (95%)
Conf  | 40.0+0.40s Threads=1 Hash=64MB
Games | N: 1000 W: 414 L: 54 D: 532
Penta | [2, 27, 181, 189, 101]

Elo   | 179.90 +- 21.43 (95%)
Conf  | 120.0+1.20s Threads=1 Hash=128MB
Games | N: 500 W: 255 L: 17 D: 228
Penta | [0, 5, 61, 125, 59]

// Potential 3.0.0 vs Stash 29
Elo   | -92.57 +- 18.84 (95%)
Conf  | 8.0+0.08s Threads=1 Hash=32MB
Games | N: 1018 W: 216 L: 481 D: 321
Penta | [118, 154, 140, 69, 28]

Elo   | -10.43 +- 22.97 (95%)
Conf  | 120.0+1.20s Threads=1 Hash=128MB
Games | N: 500 W: 144 L: 159 D: 197
Penta | [23, 61, 93, 54, 19]

Credits

Thanks to chef and rekt for the hardware support they provided me!

And a special thank you to everyone who helped me with this version!

Full Changelog: v2.0.0...v3.0.0

Second HCE release!

What's Changed

Illegal Moves Completly Gone

Fail-Hard Framework to Fail-Soft Framework

• Fail-Soft Framework, https://programcidusunur.pythonanywhere.com/test/956/

Search

Minor Features

• Root History, STC pass! by @ProgramciDusunur in #216

Major Features

• Singular Extension, STC and LTC pass! by @ProgramciDusunur in #231
• Double Extensions, STC pass! by @ProgramciDusunur in #232
• Negative Extensions, STC pass! by @ProgramciDusunur in #233
• Negative Extensions Tweak, STC pass! by @ProgramciDusunur in #236
• Triple Extensions, STC pass! by @ProgramciDusunur in #237
• Quadruple Extension, LTC pass! by @ProgramciDusunur in #306
• Low Depth Extension, STC pass! by @ProgramciDusunur in #241
• Fix Double Extension and Remove Low Depth Extension by @ProgramciDusunur in #250
• Double Negative Extension, STC pass! by @ProgramciDusunur in #288
• Triple Negative Extension and High Depth Reduction, LTC pass! by @ProgramciDusunur in #289
• Continuation History, STC pass! by @ProgramciDusunur in #290
• Reintroduce To Low Depth Extension by @ProgramciDusunur in #254
• Weight Tweak Correction History, STC pass! by @ProgramciDusunur in #278
• 2 Ply Continuation History, STC pass! by @ProgramciDusunur in #294
• 4 Ply Continuation History, STC pass! by @ProgramciDusunur in #296
• Multicut Pruning, STC pass! by @ProgramciDusunur in #308

Evaluation

• Rook Open File, STC pass! by @ProgramciDusunur in #185
• Winnable, STC pass! by @ProgramciDusunur in #192
• Rook semi open file, STC pass! by @ProgramciDusunur in #199
• Evaluation Retouch, STC pass! by @ProgramciDusunur in #264
• Add Bishop Pair Bonus by @ProgramciDusunur in #274
• Complexity, STC pass! by @ProgramciDusunur in #276
• Can Passer Pawn Bonus, STC pass! by @ProgramciDusunur in #282

Time Management

• Soft TM, STC pass! by @ProgramciDusunur in #200
• Best Move TM, STC pass! by @ProgramciDusunur in #214
• Eval TM, STC pass! by @ProgramciDusunur in #220

Bug Fix

• Fix a Few Bugs by @ProgramciDusunur in #234
• Just Reset When Uci New Game by @ProgramciDusunur in #291
• Fix Memory Leaks by @ProgramciDusunur in #302
• Another Fix For Illegal Moves by @ProgramciDusunur in #303
• Fix Array Out Of Bounds by @ProgramciDusunur in #304
• Fix Illegal Move and TT Distortions by @ProgramciDusunur in #301

Feature

• Init SEE Suit by @ProgramciDusunur in #281
• Add Perft to UCI by @ProgramciDusunur in #300
• Add README by @ProgramciDusunur in #309

Strength

// 2.0.0 vs 1.0.0
Elo   | 272.51 +- 15.91 (95%)
Conf  | 8.0+0.08s Threads=1 Hash=8MB
Games | N: 2004 W: 1431 L: 118 D: 455
Penta | [4, 24, 133, 337, 504]

Elo   | 302.97 +- 16.27 (95%)
Conf  | 40.0+0.40s Threads=1 Hash=64MB
Games | N: 2006 W: 1474 L: 65 D: 467
Penta | [1, 15, 104, 340, 543]

// Potential 2.0.0 vs Turbulence v0.0.5
Elo   | 54.41 +- 11.71 (95%)
Conf  | 8.0+0.08s Threads=1 Hash=8MB
Games | N: 2002 W: 766 L: 455 D: 781
Penta | [42, 180, 349, 285, 145]

Elo   | 3.64 +- 11.16 (95%)
Conf  | 40.0+0.40s Threads=1 Hash=64MB
Games | N: 2004 W: 655 L: 634 D: 715
Penta | [65, 246, 381, 223, 87]

• Book: 8moves_v3.epd
• Competitors: Potential 1.0.0 (CCRL 40/15 2629) / Turbulence v0.0.5 (CCRL 40/15 2961 | CCRL Blitz 2970)
• Potential 2.0.0 estimated elo ~3000

Credits

DarkNeutrino: SEE, material draw etc. direct implementation about a lot of things.
Shawn: A lot of ideas and hardware support.
Ciekce: To solve illegal moves.
Dan: Some patch ideas.
And the Stockfish discord server, I am grateful to everyone for their help!

Full Changelog: https://github.com/ProgramciDusunur/Potential/commits/v2.0.0

Potential 1.0.0

Very first HCE release!

What's Added

• MVV/LVA move ordering, STC pass! by @ProgramciDusunur in #123
• Quiet move ordering, STC pass! by @ProgramciDusunur in #124
• More priority for the pv moves, STC pass! by @ProgramciDusunur in #125
• Tt move, STC pass! by @ProgramciDusunur in #126
• TT move ordering, STC pass! by @ProgramciDusunur in #127
• Quiescence search, STC pass! by @ProgramciDusunur in #128
• Just generate captures and promotions in quiescence search, STC pass! by @ProgramciDusunur in #129
• Sort captures on quiescence search and fix quiescence explosion, STC pass! by @ProgramciDusunur in #130
• Nmp, STC pass! by @ProgramciDusunur in #131
• Aspiration Windows, STC pass! by @ProgramciDusunur in #132
• Rook open file, STC pass! by @ProgramciDusunur in #133
• Lmr, STC pass! by @ProgramciDusunur in #134
• Rfp, STC pass! by @ProgramciDusunur in #135
• Lmr non pv quiet reduction, STC pass! by @ProgramciDusunur in #136
• Futility pruning, STC pass! by @ProgramciDusunur in #137
• Iir, STC pass! by @ProgramciDusunur in #138
• Cut node iir, STC pass! by @ProgramciDusunur in #139
• Lmp, STC pass! by @ProgramciDusunur in #140
• NMP static eval fail high check, STC pass! by @ProgramciDusunur in #141
• Nmp only pawn, STC pass! by @ProgramciDusunur in #142
• More rfp, STC pass! by @ProgramciDusunur in #143
• Can passer move, STC pass! by @ProgramciDusunur in #144
• Lmr table, STC pass! by @ProgramciDusunur in #145
• Rfp improving, STC pass! by @ProgramciDusunur in #146
• Razoring, STC pass! by @ProgramciDusunur in #147
• Rook semi open file, STC pass! by @ProgramciDusunur in #148
• More LMP, STC pass! by @ProgramciDusunur in #150
• Soft tm, STC pass! by @ProgramciDusunur in #151
• Gradual aspiration windows, STC pass! by @ProgramciDusunur in #152
• Aspiration Windows tweak, STC pass! by @ProgramciDusunur in #153
• Dynamic nmp depth, STC pass! by @ProgramciDusunur in #154
• Knight outpost, STC pass! by @ProgramciDusunur in #155
• Winnable, STC pass! by @ProgramciDusunur in #156
• Mate distance pruning, STC pass! by @ProgramciDusunur in #158
• Qs see, STC pass! by @ProgramciDusunur in #160
• See pvs, STC pass! by @ProgramciDusunur in #161
• See move ordering, STC pass! by @ProgramciDusunur in #163
• Best Move TM, STC pass! by @ProgramciDusunur in #167
• Eval TM, STC pass! by @ProgramciDusunur in #168

Full Changelog: https://github.com/ProgramciDusunur/Potential/commits/v1.0.0

Strength

Elo   | -5.21 +- 13.13 (95%)
Conf  | 8.0+0.08s Threads=1 Hash=8MB
Games | N: 2000 W: 734 L: 764 D: 502
Penta | [137, 207, 344, 173, 139]
https://programcidusunur.pythonanywhere.com/test/931/
// Linux

Results of Potential_1.0.0 vs Stash_22 (8+0.08, 1t, 64MB - 16MB, 8mvs_+90_+99.epd):
Elo: -50.79 +/- 12.70, nElo: -61.81 +/- 15.23
LOS: 0.00 %, DrawRatio: 35.94 %, PairsRatio: 0.55
Games: 1998, Wins: 609, Losses: 899, Draws: 490, Points: 854.0 (42.74 %)
Ptnml(0-2): [181, 232, 359, 150, 77]
// Windows

• Book: 8moves_v3.epd
• Competitor: Stash 22 (Estimated 2770-2800)
• Potential 1.0.0 estimated elo ~2750