Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: Bit board representation

Author: Bas Hamstra

Date: 07:47:27 05/31/01

Go up one level in this thread


>I'm not a factor of 3 slower. That is your imagination working.  Somethings
>are faster in bitmaps, some slower.  You want to harp on the move generation.
>That is less than 10% of my execution time, so it doesn't count.  Evaluation
>is very good in bitmaps.

For most things, yes, but not everything. If you want to use AttacksTo info
heavily, like some tactical programs do, you have a problem doing that with
bitboards. You could do it either "on the fly"  using a couple of dozens
AttacksTo()'s and end up with a *very* low nps. The alternative would be to
calculate AttackTo tables (or even keep them incrementally). Now that is a
problem with bitboards too. It *can* be done, of course, but as a result for
instance Crafty could then divide it's nps by 4 (if not more).

(and remember I use bitboards myself)


Best regards,
Bas.




This page took 0 seconds to execute

Last modified: Thu, 15 Apr 21 08:11:13 -0700

Current Computer Chess Club Forums at Talkchess. This site by Sean Mintz.