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Subject: Thanks to Mr Fischer. Other doubt.

Author: Maurizio Di Vitto

Date: 09:29:32 01/10/04


Dear Mr Fischer,
thank you very much for your help. Maybe the question about the shift was not so
clear. I'll try to explain better.
Let's have an example, let's take the +9 movement that should be the up left
movement and let's start from the square number h1, I mean the bit number 0
(..... 00000000 00000001). If we look to the shiftR45 table we'll find that the
index is 1 (shiftR45[0]). So we have 0 9 18 27 ..., if we find RotatedR45[9],
RotatedR45[18] etc. we'll have teh fallowing b1 c1 d1 ... that mean 1 2 3, and
if we shift them of 1 unit we will have 1>>1(this bit is out) 2>>1 3>>1 .., ...
00000000 01111111, so we have seven bit. It's supposed to be all wrong, could
you explain my mistakes.
Then I don't understand why you use the A column in the right side of the
chessboard.
Another two things, what COMPACT_ATTACK_TABLES is and in the rook routine you
use ((1<<i)&(bitrow<<1)) to control if the rook meet a piece or  a bit, but why
this?
Thanks again for your time and help.
Maurizio Di Vitto



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