Author: Severi Salminen
Date: 08:46:52 12/06/01
Go up one level in this thread
>>I AM THE KING OF THE WORLD!!!! ...no?... >> >No >You are not Oh damn! Well, it felt SOOOOO good for these 2 minutes ;) >My task was not to calculate perft with make and unmake move but to calculate >perft. I don't really understand. The perft (as "defined" in crafty) does a complete search to a certain depth making and unmaking all the legal moves. So if you do perft 1 in initial position you should be making and unmaking 20 moves. And if your legality check needs making an unmaking then you obviously have to make/unmake more moves but this is about desing. But basically perft N updates the Board structure to every legal position at depth N. And we must both do the same to compare figures. >legality check is not done in my makemove and I guess that legality check is >done in your makemove. In a way, yes. I first make a move and then check if my king was left in check and if this is the case, I unmake the move as it is illegal. Do you check legality in move generation? That might not be a good idea (see below). >The main problem is that my makemove update the attack arrays and it is needed >for generating the next ply moves because my gen function generate only legal >moves not like your program. Hmm, this might not be a good idea as in normal search you will end up doing allways too much work: when you generate the last moves in quiescence search, you generate some useless info for next ply move generation, which you don't need as you will call eval(). BTW: what are these attack arrays? Some info on who is attacking who? same applies if you do legality check in move generation stage: you most likely will need that info only for the first move you try (if you have good move ordering scheme): In 95% of cases you fail high after the first tried move, so you didn't have to know if other moves were legal or not. It is very possible that I speak too much as I really don't know anything about your engine but these things were something I have had to go through with my engine. Severi
This page took 0.01 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.