Bitboard

[PauloSoare]

Why is so difficult for programmers to implement bitboards? With this implementation, the programs would benefit from 64 bits. High-level programs that I think do not use bitboards: Shredder, Hiarcs, Fritz.

[Evert]

I don't think it's difficult at all.
That said, if you already have a program based on different data structures, it may be a lot of work and not obviously worth it.

[Tord Romstad]

Why is so difficult for programmers to implement bitboards?

It isn't very difficult, it just isn't very important. The board representation simply doesn't matter all that much.

With this implementation, the programs would benefit from 64 bits.

Possibly, but only on 64-bit CPUs. The most important CPU for computer chess at the moment is the ARM, which is 32-bit. Bitboard code runs quite slowly on the ARM. This isn't the only reason everybody is not using bitboards, of course. Many programmers simply have more interesting or important things to do than fiddling with their board representation.

[rbarreira]

The most important CPU for computer chess at the moment is the ARM

Mmm why?

[Steve Maughan]

Because most chess games are played on hand held devices.

[Dann Corbit]

The most important CPU for computer chess at the moment is the ARM

Mmm why?

e.t. phone home.