A few words about the new 6.7 version of Sting.
Sting is based on Stockfish 2.1.1 as earlier.
I found a serious bug in Hash management (Stockfish 2.1.1).
Now you may use more of Hash if you can and Sting should return a correct size.
It may be very important for users of 64-bit versions to try to solve many very difficult positions.
Sting is quasi-intelligent, "one brain in one head" engine. It means that unlike some other ELO engines, Sting can try to solve tough positions ("horizon effect") without an artificial or the human intelligence based on some tricks like: Monte Carlo, null move disabling, start parameters (or versions), "rule 50", tablebases or other.
Of course, it is very important to do it without a serious ELO loss too.
I added a few tools (code) making Sting more selective. It means I diagnosed many branch of problems leading to the horizon effect.
Maybe one branch "lazy King" needs still a code, but first I will check the code of Stockfish 2.1.1 (too many bugs). The code of search and static evaluation (passed pawns) need my look too.
I decided to leave some other branch: endgame question (like KQ/KP or other) for next versions. I have an interesting idea to solve the problem of all such endgames too.
Sting needs still some solid work. But I believe that it is the only correct way.
[You must be registered and logged in to see this link.] Marek Kwiatkowski 
