Winboard Forum

What is the best board representation for 32bit CPU?

I'm planning to run my chess engine (when it's developed, will be starting development at the end of the summer) on a raspberry pi or a beagleboard and unfortunately those are 32 bit processors. It's too bad that they don't have 64bit yet so I'll have to forgo using bitboards.

Thanks.

p.s. I found this research paper http://www.doiserbia.nb.rs/img/doi/0354 ... 00011V.pdf unfortunately they didn't run move generation benchmarks o_O

Probably a ray representation, where you describe the board as a collection of rays, and have a bit set for each ray. An 4x64 table would tell you for each square and direction at what index you can find the ray running through that square in a given direction.

HGM's Ray Vectors seem quite nice specially for greater board sizes. You may have a look to 15*N or 16*N Vector Attacks, ala Reul's none bitboard New Architecture with compact blocking loops to generate captures. With 16 32-bit registers of the ARM processor one may still consider bitboards. There is a 32-bit optimized bitscan by Matt Taylor, and resource friendly 32-bit kindergarten bbs to generate sliding attacks. I am a bit skeptical concerning the performance of Vučković's Compact Chessboard Representation, thanks for posting his paper, which seems a revised version of the his (2008) ICGA Journal paper.

Indeed, the idea was that when you only have a 32-bit machine, 8x8 is already a 'larger board size'.

thanks