Search found 18434 matches

by hgm
Tue May 12, 2020 6:23 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quick history move
Replies: 6
Views: 590

Re: Quick history move

This has nothing to do with the position hash key. I usually store moves in an int32, where the high byte is the sort key, and the lower 3 bytes the fromSqr, toSqr and possibly other (e.p. or promotion) info. For the purpose of the move table the sort key would be overwritten by the moved piece (typ...
by hgm
Sun May 10, 2020 9:47 pm
Forum: Computer Chess Club: General Topics
Topic: How to make Polyglot/Bin books using Lucas Chess Step By Step
Replies: 1
Views: 225

Re: How to make Polyglot/Bin books using Lucas Chess Step By Step

I am curious: How many games per second can LucasChess load?
by hgm
Sun May 10, 2020 9:41 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Bit boards without serialization
Replies: 2
Views: 356

Re: Bit boards without serialization

What is the point? When you want to search the move, the various searches must surely be serialzied, not? If you want to serialize the searches in MVV order, you would only be interested at any given point in captures of one particular piece type. So you only test with the bitboard for that type, an...
by hgm
Sun May 10, 2020 11:58 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quick history move
Replies: 6
Views: 590

Re: Quick history move

True, but it is by no means certain that the proposed metod does that any worse than conventional history. One example I can see is that it prefers recently successful moves over older ones.
by hgm
Sun May 10, 2020 9:22 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quick history move
Replies: 6
Views: 590

Re: Quick history move

Why would that be inefficient? Most moves will be 'intrinsically useless', and never cause any cutoffs. For those moves there is nothing to keep track of in the first place, so who cares if they are not in the move hash? And the size of the move hash table can always be increased. Conventional histo...
by hgm
Sat May 09, 2020 9:41 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Quick history move
Replies: 6
Views: 590

Quick history move

I am looking for an alternative to the history heuristic for which I don't have to generate all those non-captures first. Like killer, where you can search them after just testing their pseudo-legality. I was thinking of the following: I keep a small hash table of cut-moves, with 256 entries, say. O...
by hgm
Sat May 09, 2020 5:31 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Taboo moves
Replies: 3
Views: 460

Re: Taboo moves

I don't think 'transposition table' is a good analogy. The TT stores good moves per positions . Here you want to inherit info about bad moves from other positions . 'Killer' also doesn't have quite the right ring, because killers are inherited from sibling nodes, and here you inherit from (possibly ...
by hgm
Thu May 07, 2020 11:54 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Rejecting xboad features
Replies: 3
Views: 335

Re: Rejecting xboad features

I think part of the mess is due to an attempt to cater to existing non-compliant engines. For instance, it makes no sense at all to suppress sending of certain commands; the specs require the engine to respond with "Unknown command..." to any such command, and GUIs usually ignore that anyway. So why...
by hgm
Thu May 07, 2020 9:31 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: front-ending
Replies: 22
Views: 1115

Re: front-ending

However, it might just be simpler to implement fen than to implement drops (or roughly as simple). Well, of course all of this is dead simple. Even providing an existing engine that has a non-standard command-line interface with enough CECP understanding to play automated games with it under XBoard...