New engine _Crab_ based on StockFish

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Look

New engine _Crab_ based on StockFish

Post by Look » Wed Jun 09, 2010 7:30 pm

Hi,

Here is code of a new engine based on StockFish 1.7.1 called Crab 1.0 beta. Changes in it are few mostly in evaluate.cpp. Some hacks was made in it to compile it for myself, so let me know if it could not be compiled correctly. Consider Crab as a new personality of SF. Do not care about its strength though, its Crab!
http://www.mediafire.com/?ztewrmyjyhe

Dann Corbit
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Re: New engine _Crab_ based on StockFish

Post by Dann Corbit » Wed Jun 09, 2010 7:50 pm

Are there important differences besides the changes to these two arrays?

Code: Select all

// Isolated pawn penalty by file
const Score IsolatedPawnPenalty[8] = {
    S(25, 30), S(36, 35), S(40, 35), S(40, 35),
    S(40, 35), S(40, 35), S(36, 35), S(25, 30)
};

// Pawn chain membership bonus by file
const Score ChainBonus[8] = {
    S(11,-1), S(13,-1), S(13,-1), S(14,-1),
    S(14,-1), S(13,-1), S(13,-1), S(11,-1)
};

Code: Select all

// Isolated pawn penalty by file
const Score IsolatedPawnPenalty[8] = {//mmm
    S(22, 27), S(32, 32), S(36, 32), S(36, 32),
    S(36, 32), S(36, 32), S(32, 32), S(22, 27)
};

// Pawn chain membership bonus by file
const Score ChainBonus[8] = {//mmm
    S(11,0), S(13,0), S(13,0), S(14,0),
    S(14,0), S(13,0), S(13,0), S(11,0)
};

Look

Re: New engine _Crab_ based on StockFish

Post by Look » Wed Jun 09, 2010 8:00 pm

Well as usual I forgot to tell some key points. I have tried to make changes clear by using // mmm comments. Search for them in the code and compare to official SF 1.7.1 . Among changes are RookOutpostBonus, QueenOutpostBonus bonuses and new functions is_pure_pawn_eg, is_single_same_piece_eg. To see its style of play you may simply watch its games and see if it plays differently.

Dann Corbit
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Joined: Wed Mar 08, 2006 7:57 pm
Location: Redmond, WA USA
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Re: New engine _Crab_ based on StockFish

Post by Dann Corbit » Wed Jun 09, 2010 8:07 pm

Look wrote:Well as usual I forgot to tell some key points. I have tried to make changes clear by using // mmm comments. Search for them in the code and compare to official SF 1.7.1 . Among changes are RookOutpostBonus, QueenOutpostBonus bonuses and new functions is_pure_pawn_eg, is_single_same_piece_eg. To see its style of play you may simply watch its games and see if it plays differently.
Thanks.

Look

Re: New engine _Crab_ based on StockFish

Post by Look » Wed Jun 09, 2010 8:40 pm

Well as usual I forgot to tell some key points. I have tried to make changes clear by using // mmm comments. Search for them in the code and compare to official SF 1.7.1 . Among changes are RookOutpostBonus, QueenOutpostBonus bonuses and new functions is_pure_pawn_eg, is_single_same_piece_eg. To see its style of play you may simply watch its games and see if it plays differently.

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Dr.Wael Deeb
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Re: New engine _Crab_ based on StockFish

Post by Dr.Wael Deeb » Wed Jun 09, 2010 8:50 pm

Look wrote:Well as usual I forgot to tell some key points. I have tried to make changes clear by using // mmm comments. Search for them in the code and compare to official SF 1.7.1 . Among changes are RookOutpostBonus, QueenOutpostBonus bonuses and new functions is_pure_pawn_eg, is_single_same_piece_eg. To see its style of play you may simply watch its games and see if it plays differently.
You're repeating yourself....
Dr.D
_No one can hit as hard as life.But it ain’t about how hard you can hit.It’s about how hard you can get hit and keep moving forward.How much you can take and keep moving forward….

Look

Re: New engine _Crab_ based on StockFish

Post by Look » Wed Jun 09, 2010 9:21 pm

Hi Dr.D,
The good news is that it would not make me anymore psycho , you know...

mcostalba
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Joined: Sat Jun 14, 2008 7:17 pm

Re: New engine _Crab_ based on StockFish

Post by mcostalba » Wed Jun 09, 2010 10:08 pm

Look wrote:Hi,

Here is code of a new engine based on StockFish 1.7.1 called Crab 1.0 beta. Changes in it are few mostly in evaluate.cpp. Some hacks was made in it to compile it for myself, so let me know if it could not be compiled correctly. Consider Crab as a new personality of SF. Do not care about its strength though, its Crab!
http://www.mediafire.com/?ztewrmyjyhe
Nice ! As soon as we come out fom this regression nightmare (see the other thread) I will take a look at it.

BTW have you tested Crab against 1.7.1 and found it is stronger (please say yes ;-) ), and how you tested it, I mean how many games and with what time control ?

Albert Silver
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Location: Rio de Janeiro, Brazil

Re: New engine _Crab_ based on StockFish

Post by Albert Silver » Wed Jun 09, 2010 11:50 pm

Look wrote:Hi,

Here is code of a new engine based on StockFish 1.7.1 called Crab 1.0 beta. Changes in it are few mostly in evaluate.cpp. Some hacks was made in it to compile it for myself, so let me know if it could not be compiled correctly. Consider Crab as a new personality of SF. Do not care about its strength though, its Crab!
http://www.mediafire.com/?ztewrmyjyhe
I don't suppose you, or someone else could compile it pls?
"Tactics are the bricks and sticks that make up a game, but positional play is the architectural blueprint."

Look

Re: New engine _Crab_ based on StockFish

Post by Look » Thu Jun 10, 2010 11:18 am

Hi,

@Albert Silver

Sorry I am not good at compiling, so I am leaving it to others who are.

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