Computer Chess Club Archives


Search

Terms

Messages

Subject: Re: about in_check()

Author: Sune Fischer

Date: 07:15:31 06/15/03

Go up one level in this thread



>I guess the programs that use this method, like Crafty, also have a special
>get_out_of_check() move generator. When in check the possible moves are very
>limited:
>
>- capture the checking piece (if it is only one)
>- put another piece between the king and the checker (if it is a slider)
>- move the king away from the attacked ray
>- now you are really desperate - try an en passant capture!
>
>Most of these will not move you into (another) check, so it will reduce the
>cost.

Exactly.

>>Secondly you need to know you are in check so you can _extend_.
>>
>
>or you can extend on moving out of check. You know you are there because you use
>the special get_out_of_check routine.  :-)

You've lost me.
If you don't check for anyhing you don't know anything.
How it is possible to apply an extension even for the get_out_of_check?
How will you know to call a get_out_of_check routine if you don't know you're in
check?

Suppose you are in check, you happen to search the capture of the checking piece
first. Now you are out of check and the position is perfectly legal. You've now
searched this move without extending it. How do you fix that?

-S.

>
>
>
>Bo Persson
>bop2@telia.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.