- // Danger of enemy pawns moving toward our king by [type][distance from edge][rank].
- // For the unopposed and unblocked cases, RANK_1 = 0 is used when opponent has
- // no pawn on the given file, or their pawn is behind our king.
- const Value StormDanger[][4][RANK_NB] = {
- { { V( 0), V(-290), V(-274), V(57), V(41) }, // BlockedByKing
- { V( 0), V( 60), V( 144), V(39), V(13) },
- { V( 0), V( 65), V( 141), V(41), V(34) },
- { V( 0), V( 53), V( 127), V(56), V(14) } },
- { { V( 4), V( 73), V( 132), V(46), V(31) }, // Unopposed
- { V( 1), V( 64), V( 143), V(26), V(13) },
- { V( 1), V( 47), V( 110), V(44), V(24) },
- { V( 0), V( 72), V( 127), V(50), V(31) } },
- { { V( 0), V( 0), V( 79), V(23), V( 1) }, // BlockedByPawn
- { V( 0), V( 0), V( 148), V(27), V( 2) },
- { V( 0), V( 0), V( 161), V(16), V( 1) },
- { V( 0), V( 0), V( 171), V(22), V(15) } },
- { { V(22), V( 45), V( 104), V(62), V( 6) }, // Unblocked
- { V(31), V( 30), V( 99), V(39), V(19) },
- { V(23), V( 29), V( 96), V(41), V(15) },
- { V(21), V( 23), V( 116), V(41), V(15) } }
+ // Danger of enemy pawns moving toward our king by [distance from edge][rank].
+ // RANK_1 = 0 is used for files where the enemy has no pawn, or their pawn
+ // is behind our king. Note that UnblockedStorm[0][1-2] accommodate opponent pawn
+ // on edge, likely blocked by our king.
+ constexpr Value UnblockedStorm[int(FILE_NB) / 2][RANK_NB] = {
+ { V( 87), V(-288), V(-168), V( 96), V( 47), V( 44), V( 46) },
+ { V( 42), V( -25), V( 120), V( 45), V( 34), V( -9), V( 24) },
+ { V( -8), V( 51), V( 167), V( 35), V( -4), V(-16), V(-12) },
+ { V(-17), V( -13), V( 100), V( 4), V( 9), V(-16), V(-31) }