Bit boards without serialization

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MOBMAT
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Bit boards without serialization

Post by MOBMAT » Sun May 10, 2020 8:19 pm

Thought experiment: Generating moves with bit boards without a serialized board to help out.

problem occurs with capture moves when deciding what piece was captured. without serialization, 6 tests must be made to see which piece is being captured. there might be some other considerations, but captures are what came to mind.

if one does not want to not use the additional brd[64] type array, what is the state of the art workarounds? perhaps there isn't one, but everything has trade-offs.
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hgm
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Re: Bit boards without serialization

Post by hgm » Sun May 10, 2020 9:41 pm

What is the point? When you want to search the move, the various searches must surely be serialzied, not? If you want to serialize the searches in MVV order, you would only be interested at any given point in captures of one particular piece type. So you only test with the bitboard for that type, and you know what piece is captured by the moves that remain. If there is more than one such capture, you still have to search them one by one. You cannot make both captures at once...

smatovic
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Re: Bit boards without serialization

Post by smatovic » Wed May 13, 2020 1:06 pm

I use Quad-Bitboards in Zeta wihtout brd[64] type array...

https://www.chessprogramming.org/Quad-Bitboards

https://github.com/smatovic/Zeta/blob/m ... ta.cl#L104

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