eschac 0.6.1

computing chess moves
Documentation 
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use crate::bitboard::*;
use crate::board::*;

pub(crate) use crate::util::*;

#[repr(align(8))]
struct Data<'a> {
	inner: &'a [u8],
}
impl<'a> Data<'a> {
	const fn new(inner: &'a [u8]) -> Self {
		Self { inner }
	}
	fn read(&self, index: usize) -> u64 {
		let i = index << 3;
		u64::from_le_bytes(self.inner.get(i..i + 8).unwrap().try_into().unwrap())
	}
}

static MAGIC: Data = Data::new(include_bytes!(concat!(env!("OUT_DIR"), "/magic.bin")));
static TABLE: Data = Data::new(include_bytes!(concat!(env!("OUT_DIR"), "/table.bin")));

#[inline]
pub(crate) fn bishop(square: Square, blockers: Bitboard) -> Bitboard {
	aux(0, BISHOP_SHR, square, blockers)
}

#[inline]
pub(crate) fn rook(square: Square, blockers: Bitboard) -> Bitboard {
	aux(1, ROOK_SHR, square, blockers)
}

#[inline]
pub(crate) fn aux(j: usize, shr: u8, square: Square, blockers: Bitboard) -> Bitboard {
	let i = square.index() as usize + j * 64;
	let premask = Bitboard(MAGIC.read(3 * i));
	let factor = MAGIC.read(3 * i + 1);
	let offset = MAGIC.read(3 * i + 2) as isize;
	let value = TABLE.read(((hash(shr, factor, blockers | premask) as isize) + offset) as usize);
	Bitboard(value)
}

#[cfg(feature = "alloc")]
#[test]
fn test_magic_data() {
	let (magic, table) = crate::magic::build();
	assert_eq!(&magic, &MAGIC.inner);
	assert_eq!(&table, &TABLE.inner);
	assert_eq!(table.len(), 869848);
}