X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fpawns.cpp;h=2fc8e73666fb78e94d46b75f0dca635f80e6b280;hp=d8d8243fc9570ab08b1cb7233544fabd7e8e61cf;hb=480682b67097160bfc25e52ab02facffeec104f0;hpb=89d9db2979b823449f8f0574617becc33de88607 diff --git a/src/pawns.cpp b/src/pawns.cpp index d8d8243f..2fc8e736 100644 --- a/src/pawns.cpp +++ b/src/pawns.cpp @@ -194,19 +194,24 @@ namespace { namespace Pawns { +/// init() initializes some tables used by evaluation. Instead of hard-coded +/// tables, when makes sense, we prefer to calculate them with a formula to +/// reduce independent parameters and to allow easier tuning and better insight. + void init() { - const int c[RANK_NB] = {0, 6, 15, 10, 57, 75, 135, 258}; + static const int Seed[RANK_NB] = { 0, 6, 15, 10, 57, 75, 135, 258 }; - for (Rank r = RANK_2; r <= RANK_7; ++r) - for (int opposed = false; opposed <= true; ++opposed) - for (int phalanx = false; phalanx <= true; ++phalanx) + for (int opposed = 0; opposed <= 1; ++opposed) + for (int phalanx = 0; phalanx <= 1; ++phalanx) + for (Rank r = RANK_2; r < RANK_8; ++r) { - int bonus = c[r] + (phalanx ? (c[r + 1] - c[r]) / 2 : 0); + int bonus = Seed[r] + (phalanx ? (Seed[r + 1] - Seed[r]) / 2 : 0); Connected[opposed][phalanx][r] = make_score(bonus / 2, bonus >> opposed); } } + /// probe() takes a position as input, computes a Entry object, and returns a /// pointer to it. The result is also stored in a hash table, so we don't have /// to recompute everything when the same pawn structure occurs again.