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Subject: Re: Attack Table Question

Author: Daniel Shawul

Date: 03:38:17 03/23/04

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On March 22, 2004 at 16:18:19, Anthony Cozzie wrote:

>On March 22, 2004 at 03:40:57, Daniel Shawul wrote:
>
>>Hello
>>
>>I have decided to use attack tables. I just did
>>a rough implementation of it at the beginning of the eval
>>according to Ed's paper. The problem is the thing dropped the nodecount
>>by almost 40% .  Initial position nodecount was 800000 and now it is 500000.
>>Do incremental move attack tables help? And how do i update the table? It seems
>>very difficult to update a sliding move and other special cases.
>>
>>thanks
>>daniel
>
>I have some code for incremental attack tables if you want it.  However, it took
>Tord 4 months to figure out :)  I don't use attack tables in Zappa; i wrote this
>when i was considering switching to a piecelist based engine.
>
>anthony


I would appreciate if you do send me the relevant part.
Another problem i am seeing   I need to use a larger data type [other than 8
bits] if i have to use incremental attack tables. And this causes indexing very
difficult[the thing i liked most about rebel's method]. with the previous one,
you have also to keep track of the count of attacks by each piece. If you don't
use that , what will you do when the knight attacks decrease from two to one.How
do i know to turn off the knight attack bit if i don't keep track the count.  My
guess is i have to use a short and that completely leaves out the indexing
scheme.If the incremental is not more faster , i don't see any reason for using
that.
daniel



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