Search found 2885 matches

by Evert
Thu Jan 03, 2019 3:32 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Generate EGTB with graphics cards?
Replies: 29
Views: 1546

Re: Generate EGTB with graphics cards?

From what I recall, tablebase generation is generally I/O bound, not CPU bound. A tablebase generator typically uses an algorithm like this: 1. Allocate a bitlist for all possible positions 2. Mark all “lost” positions 3. Retro-move from all positions found in 2/5: these positions are “won”. 4. Retr...
by Evert
Thu Dec 20, 2018 3:22 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: UCI pondering done right
Replies: 52
Views: 1965

Re: UCI pondering done right

Bad naming of commands, like hard/easy to means pondering on/off is a much major flaw that makes many programmers (including me) to flee away from the winboard protocol. Well, “hard” means “switch the engine to hard difficulty”, which implied that it would ponder, in some old version of GNU Chess. ...
by Evert
Sun Dec 09, 2018 9:52 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Texel tuning for piece values
Replies: 12
Views: 957

Re: Texel tuning for piece values

There also is little need to do it, because Larry Kaufman already did it for us, and shared the results. ok I get that but why Rofchade get pieces value like those then const eval pieceValue[2][6] = { 82, 337, 365, 477, 1025, 12000, 94, 281, 297, 512, 936, 12000 }; Why not use 100 as MG pawn value ...
by Evert
Fri Nov 16, 2018 8:01 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Any Fortran coder ?
Replies: 26
Views: 1653

Re: Any Fortran coder ?

i have no problem writing code to handle the UCI interface for now, in fact the only thing i wrote in my engine for now is the UCI parser. Which lead me to my current problem. Writing a UCI parser in Fortran isn’t the main issue (although I never found Fortran string manipulation particularly conve...
by Evert
Fri Nov 16, 2018 6:26 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Any Fortran coder ?
Replies: 26
Views: 1653

Re: Any Fortran coder ?

I worked with Fortran for about ten years, up to a few years ago. Mainly for floating point calculations though, I never really used its bitwise operators, but I seem to recall they’re overly verbose. Fortran’s main strengths, as I see it, are its array block operations and auto-parallelisable loops...
by Evert
Sat Aug 11, 2018 9:05 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Attacks From table
Replies: 12
Views: 2200

Re: Attacks From table

I think you can do better by testing for alignment first, and only then doing a lookup for the actual piece (your xxxAttacksBB functions) if there is alignment. You probably also want to do that in a ray-direction way, rather than by full rank/file/diagonal. You can cache the attack information for ...
by Evert
Mon Jul 30, 2018 6:16 am
Forum: Computer Chess Club: General Topics
Topic: Off topic - Who is authorized?
Replies: 6
Views: 848

Re: Off topic - Who is authorized?

You need to be logged in to view profiles now, I think.
by Evert
Thu Jun 21, 2018 11:37 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: about the value of fairy pieces
Replies: 10
Views: 1917

Re: about the value of fairy pieces

I think it's important to make a distinction between opening and end game values. I can imagine Crab/Barc beating a Knight in the end game simply because the Knight cannot easily defend both flanks. I also believe that the value difference between Q and B/R goes down in the end game. What would be a...
by Evert
Thu Jun 21, 2018 5:00 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: about the value of fairy pieces
Replies: 10
Views: 1917

Re: about the value of fairy pieces

But suppose you replace Pawns by (promoting) Ferzes (or allow FIDE Pawns to capture backwards, fmWcF). These make chains that are self-protecting, and can only be damaged at the expense of the first attacker. So it would be more helpful to have two pieces, one of which less valuable than a pair of ...
by Evert
Wed Jun 20, 2018 9:14 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: about the value of fairy pieces
Replies: 10
Views: 1917

Re: about the value of fairy pieces

Seems contrived on a normal board, normal rules and an otherwise balanced army. It would imply that B and C are due some sort of synergy bonus (generalised pair bonus) that is larger when the pieces are further apart (or at least, not on the same square). The effect HGM mentions is of course also im...