Search found 215 matches

by MahmoudUthman
Fri Jul 26, 2019 3:16 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: SF' MidgameLimit & EndgameLimit ?
Replies: 2
Views: 1155

SF' MidgameLimit & EndgameLimit ?

what is the basis for the current values of SF's {MidgameLimit = 15258, EndgameLimit = 3915}, and what do they represent exactly?
for example the last time they were changed was when the linear imbalance was removed even though the MG values of the pieces changed later.
by MahmoudUthman
Thu Jun 06, 2019 4:28 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: correct way to score promotions using MVV-LVA
Replies: 6
Views: 1204

correct way to score promotions using MVV-LVA

Stockfish used to do this for captures: for (auto& m : *this) if (type_of(m) == ENPASSANT) m.value = PieceValue[MG][PAWN] - Value(PAWN); else if (type_of(m) == PROMOTION) m.value = PieceValue[MG][pos.piece_on(to_sq(m))] - Value(PAWN) + PieceValue[MG][promotion_type(m)] - PieceValue[MG][PAWN]; else m...
by MahmoudUthman
Tue Jun 04, 2019 10:24 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: is LVA as in MVV-LVA useless ?
Replies: 9
Views: 1760

is LVA as in MVV-LVA useless ?

Looking at SF's code it seems to be ordering captures & promotions using MVV only + CaptureHistory, and according to this pull the LVA part is insignificant or even useless, unfortunately I don't have the resources to test such a -"is (such a) right here or should it be just (such)"- subtle differen...
by MahmoudUthman
Tue Apr 02, 2019 3:49 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Any testing framwork similair to Fishtest that can be run locally ?
Replies: 3
Views: 1170

Any testing framwork similair to Fishtest that can be run locally ?

Is there any testing framework similar to Fish-test that can be run locally to test my own engine ?
I have multiple PCs that I would like to use in testing, but I don't know how to manage them all at once.
by MahmoudUthman
Thu Mar 14, 2019 9:16 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: CPW bitscan with reset could someone explain this line?
Replies: 9
Views: 1339

CPW bitscan with reset could someone explain this line?

on the wiki : While traversing sets, one may combine bitscanning with reset found bit. That implies passing the bitboard per reference or pointer, and tends to confuse compilers to keep all inside registers inside a typical serialization loop [22] . int bitScanForwardWithReset(U64 &bb) { // also cal...
by MahmoudUthman
Sun Jan 06, 2019 3:32 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Pruning at PV nodes?
Replies: 2
Views: 594

Pruning at PV nodes?

In a Principal variation search, what type of "useful +elo" pruning do you use at PV-nodes ?
by MahmoudUthman
Tue Dec 25, 2018 12:56 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: piece lists advantage with bit-boards?
Replies: 16
Views: 1960

Re: piece lists advantage with bit-boards?

Any scheme that allows more data to be stored and accessed cleanly and efficiently has potential to have substantial advantages if a use case exist. Having indexed pieces allows for a specific piece to piece structure mapping that a piece type bitboard would seem to lack. Maybe one might want to kn...
by MahmoudUthman
Mon Dec 24, 2018 10:35 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: piece lists advantage with bit-boards?
Replies: 16
Views: 1960

piece lists advantage with bit-boards?

does a bit-board based position representation with piece lists offer any advantage over a bit-board? & is it dependent on the architecture & the presence of bit-scan instructions?
by MahmoudUthman
Fri Oct 19, 2018 11:00 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: a couple of questions regarding engine testing ?
Replies: 3
Views: 811

a couple of questions regarding engine testing ?

1-Should hyper-threading and Intel turbo-boost be disabled or is it okay to leave them on? 2-Do I always need to retest using LTCs, or does it depend on the Elo difference between the old & new version of the engine ? 3-Can I run fish-test locally, and use it to manage tests for my engine,or is it h...