- {
- SquareDistance[s1][s2] = std::max(file_distance(s1, s2), rank_distance(s1, s2));
- if (s1 != s2)
- DistanceRingsBB[s1][SquareDistance[s1][s2] - 1] |= s2;
- }
-
- int steps[][9] = { {}, { 7, 9 }, { 17, 15, 10, 6, -6, -10, -15, -17 },
- {}, {}, {}, { 9, 7, -7, -9, 8, 1, -1, -8 } };
-
- for (Color c = WHITE; c <= BLACK; ++c)
- for (PieceType pt = PAWN; pt <= KING; ++pt)
- for (Square s = SQ_A1; s <= SQ_H8; ++s)
- for (int k = 0; steps[pt][k]; k++)
- {
- Square to = s + Square(c == WHITE ? steps[pt][k] : -steps[pt][k]);
-
- if (is_ok(to) && square_distance(s, to) < 3)
- StepAttacksBB[make_piece(c, pt)][s] |= to;
- }