Use a Direction enum for Square deltas

Currently the NORTH/WEST/SOUTH/EAST values are of type Square, but conceptually they are not squares but directions. This patch separates these values into a Direction enum and overloads addition and subtraction to allow adding a Square to a Direction (to get a new Square).

I have also slightly trimmed the possible overloadings to improve type safety. For example, it would normally not make sense to add a Color to a Color or a Piece to a Piece, or to multiply or divide them by an integer. It would also normally not make sense to add a Square to a Square.

This is a non-functional change.
This commit is contained in:
syzygy1
2017-12-04 17:52:31 +01:00
committed by Marco Costalba
parent 2acda1fde3
commit 822695d4d3
10 changed files with 81 additions and 63 deletions

View File

@@ -524,7 +524,7 @@ ScaleFactor Endgame<KRPKB>::operator()(const Position& pos) const {
Square bsq = pos.square<BISHOP>(weakSide);
Square psq = pos.square<PAWN>(strongSide);
Rank rk = relative_rank(strongSide, psq);
Square push = pawn_push(strongSide);
Direction push = pawn_push(strongSide);
// If the pawn is on the 5th rank and the pawn (currently) is on
// the same color square as the bishop then there is a chance of