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Subject: Re: Question:1.hashtable 2.board 3.C

Author: Tom Kerrigan

Date: 11:13:11 06/14/00

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On June 13, 2000 at 23:10:51, Christophe Theron wrote:

>On June 13, 2000 at 17:06:57, Tom Kerrigan wrote:
>
>>On June 13, 2000 at 16:10:05, Christophe Theron wrote:
>>
>>>With the other approach, you need a table lookup to tell that the square is not
>>>inside the board:
>>>
>>>  // 12x12 way:
>>>  if (board[square]==-1) it_is_outside;
>>>  else                   it_is_inside;
>>
>>If your board starts out being 12x12, then you're right, it doesn't really make
>>a difference if you switch to 0x88.
>>
>>However, I know that a number of programs use an 8x8 board. To do the bounds
>>testing, they convert the 8x8 offset into a 10x12 offset and then back again.
>>You can see this done in TSCP. This method is obviously a loser compared to
>>0x88.
>
>
>I don't really understand why you would use a 8x8 board if you use 12x12
>coordinates or the opposite...

Probably because it's easier to understand and it gives you a nice advantage if
you're worried about wasted space in arrays (or packing move coordinates into a
certain number of bits).

-Tom



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