Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: move ordering question

Author: William Bryant

Date: 18:10:07 03/01/00

Go up one level in this thread


On March 01, 2000 at 20:40:48, John Coffey wrote:

>On March 01, 2000 at 17:03:44, William Bryant wrote:
>
>
>>Break down your move generator into two functions, one that generates captures
>>and promotions, and one that generates only non-captures.  Hopefully, one
>>of the captures will generate a cutoff and the non-captures will not have
>>to be generated at all.
>>
>
>It is hard for me to imagine how this can be done at all?  Seems like generating
>the captures would also require you to generate the non-captures.
>
>I assume that the only way this can be done is with bitboards?
>
>John


Not at all, (although bitboards do improve the efficiency I would think)
To generate captures only, only accept the moves that have a piece of the
opposite color on the 'to' square.  To generate non-caputures, only accept
the moves that move to an empty square.

That said, the efficiency of generating captures and non-captures separately
on a non-bitboard based program may be poor enough (may almost double the work),
that the benefit of doing them separately may be of little value.

Just sbe sure to flag your moves so that they can be ordered correctly.

YMMV (Your milage may vary)

William
wbryant@ix.netcom.com



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.