Search found 219 matches

by Sergei S. Markoff
Wed Sep 14, 2011 5:59 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: c# for chess engine
Replies: 15
Views: 3898

Re: c# for chess engine

Do you know your rgstat timing for 10k games is? I just spent weeks rewriting move generation in my c# engine to use a pseudolegal move generator and the most I can get is about 170 games per second. I'm using bitboards and piece-square arrays. That's like 10 times slower than C engines so I'm not ...
by Sergei S. Markoff
Wed Sep 14, 2011 5:56 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Repetitions/50 moves and TT
Replies: 27
Views: 7264

Re: Repetitions/50 moves and TT

bob wrote:How can you do that? When you get a hash hit, you don't have the path that was searched to store the position...
At least partially -- we have. We can search TT to extract stored part of the subtree and verify it.
by Sergei S. Markoff
Wed Sep 14, 2011 5:48 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Way to reduce amount of stored data in engine
Replies: 9
Views: 1489

Re: Way to reduce amount of stored data in engine

The real question is where you want to save space. If you want to save space on the hard-disk you can use the packed huffman data and if you want to use it in game play you can convert it to a hashed position-move database. Anyway I think this format is much more helpful for large databases of game...
by Sergei S. Markoff
Wed Sep 14, 2011 12:35 am
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Way to reduce amount of stored data in engine
Replies: 9
Views: 1489

Re: Way to reduce amount of stored data in engine

Huffman is a very compact way to express the moves themselves and a good idea, however you still have to have some structure to this, for example you need to be able to reference a position. If you use a tree structure your pointers are at least 32 bits. So how do you figure out where to start look...
by Sergei S. Markoff
Tue Sep 13, 2011 8:03 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Way to reduce amount of stored data in engine
Replies: 9
Views: 1489

Re: Way to reduce amount of stored data in engine

At practice you can use something like Huffman tree. Let's assume that you have move generator with some clever ordering. For example, based on quiescence search. It produces a list of moves, where the 1st move is the best one, 2nd — next to the first and so on. Then you just analyzes every node of ...
by Sergei S. Markoff
Tue Sep 13, 2011 7:30 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Repetitions/50 moves and TT
Replies: 27
Views: 7264

Re: Repetitions/50 moves and TT

That only addresses 1/2 of the problem. What about the positions where you retrieve a score that is NOT a draw-based score, but the current path you are searching when extended by the path leading to the TT hit actually passes over a repetition or 50 move draw but you don't know? This is a far more...
by Sergei S. Markoff
Tue Sep 13, 2011 7:25 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: c# for chess engine
Replies: 15
Views: 3898

Re: c# for chess engine

Steve Maughan wrote:If the C version of SmarThink has been retired, how about releasing it as Freeware? Just an idea (I'd happily host it).
Steve
Let see, may be I will do it. I need to discuss it with Lokasoft of course.
by Sergei S. Markoff
Tue Sep 13, 2011 7:06 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: c# for chess engine
Replies: 15
Views: 3898

Re: c# for chess engine

SmarThink is written on plain C. The coding was started in 2000, when I wasn't very experienced. Finally that code is hard to manage now. I'm planning to write new engine on c#, using SmarThink parts of course. Now I have some beta, w/o most of neccessary parts. I don't know how much time I can spen...
by Sergei S. Markoff
Tue Sep 13, 2011 6:43 pm
Forum: Computer Chess Club: Programming and Technical Discussions
Topic: Repetitions/50 moves and TT
Replies: 27
Views: 7264

Re: Repetitions/50 moves and TT

Later I found an old (1985) article by Murray Campbell that describes this technique in more detail. With google you might find a free pdf. For example here: The graph-history interaction: on ignoring position history PS: I also observe occasional problems in mating in KRK btw but I think in my pro...