From: hxim Date: Sun, 7 Feb 2016 20:58:20 +0000 (+0000) Subject: Remove Weights X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=56dd58e6f9d9073b963ebf2add7da9723eb5cd5a;ds=sidebyside Remove Weights Removed remaining redundant weights for pawn structure, passed pawns, space and king safety by redistributing them into individual evaluation terms. STC: LLR: 2.96 (-2.94,2.94) [-3.00,1.00] Total: 15173 W: 2790 L: 2659 D: 9724 LTC: LLR: 2.96 (-2.94,2.94) [-3.00,1.00] Total: 43433 W: 5936 L: 5846 D: 31651 Bench: 7156237 Resolves #586 --- diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 9b3c4bc2..fe020fac 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -107,18 +107,6 @@ namespace { Pawns::Entry* pi; }; - - // Evaluation weights, indexed by the corresponding evaluation term - enum { PawnStructure, PassedPawns, Space, KingSafety }; - - const struct Weight { int mg, eg; } Weights[] = { - {214, 203}, {193, 262}, {47, 0}, {330, 0} }; - - Score operator*(Score s, const Weight& w) { - return make_score(mg_value(s) * w.mg / 256, eg_value(s) * w.eg / 256); - } - - #define V(v) Value(v) #define S(mg, eg) make_score(mg, eg) @@ -180,14 +168,14 @@ namespace { // Passed[mg/eg][Rank] contains midgame and endgame bonuses for passed pawns. // We don't use a Score because we process the two components independently. const Value Passed[][RANK_NB] = { - { V(0), V( 1), V(34), V(90), V(214), V(328) }, - { V(7), V(14), V(37), V(63), V(134), V(189) } + { V(0), V( 1), V(26), V(68), V(161), V(247) }, + { V(7), V(14), V(38), V(64), V(137), V(193) } }; // PassedFile[File] contains a bonus according to the file of a passed pawn const Score PassedFile[FILE_NB] = { - S( 12, 10), S( 3, 10), S( 1, -8), S(-27,-12), - S(-27,-12), S( 1, -8), S( 3, 10), S( 12, 10) + S( 9, 10), S( 2, 10), S( 1, -8), S(-20,-12), + S(-20,-12), S( 1, -8), S( 2, 10), S( 9, 10) }; // Assorted bonuses and penalties used by evaluation @@ -627,10 +615,10 @@ namespace { else if (defendedSquares & blockSq) k += 4; - mbonus += k * rr, ebonus += k * rr; + mbonus += k * rr * 3 / 4, ebonus += k * rr; } else if (pos.pieces(Us) & blockSq) - mbonus += rr * 3 + r * 2 + 3, ebonus += rr + r * 2; + mbonus += (rr * 3 + r * 2 + 3) * 3 / 4, ebonus += rr + r * 2; } // rr != 0 if (pos.count(Us) < pos.count(Them)) @@ -640,10 +628,10 @@ namespace { } if (DoTrace) - Trace::add(PASSED, Us, score * Weights[PassedPawns]); + Trace::add(PASSED, Us, score); // Add the scores to the middlegame and endgame eval - return score * Weights[PassedPawns]; + return score; } @@ -682,7 +670,7 @@ namespace { int weight = pos.count(Us) + pos.count(Us) + pos.count(Them) + pos.count(Them); - return make_score(bonus * weight * weight, 0); + return make_score(bonus * weight * weight * 2 / 11, 0); } @@ -771,7 +759,7 @@ Value Eval::evaluate(const Position& pos) { // Probe the pawn hash table ei.pi = Pawns::probe(pos); - score += ei.pi->pawns_score() * Weights[PawnStructure]; + score += ei.pi->pawns_score(); // Initialize attack and king safety bitboards ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0; @@ -821,8 +809,8 @@ Value Eval::evaluate(const Position& pos) { // Evaluate space for both sides, only during opening if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) >= 12222) - score += ( evaluate_space(pos, ei) - - evaluate_space(pos, ei)) * Weights[Space]; + score += evaluate_space(pos, ei) + - evaluate_space(pos, ei); // Evaluate position potential for the winning side score += evaluate_initiative(pos, ei.pi->pawn_asymmetry(), eg_value(score)); @@ -841,10 +829,10 @@ Value Eval::evaluate(const Position& pos) { { Trace::add(MATERIAL, pos.psq_score()); Trace::add(IMBALANCE, ei.me->imbalance()); - Trace::add(PAWN, ei.pi->pawns_score() * Weights[PawnStructure]); + Trace::add(PAWN, ei.pi->pawns_score()); Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]); - Trace::add(SPACE, evaluate_space(pos, ei) * Weights[Space] - , evaluate_space(pos, ei) * Weights[Space]); + Trace::add(SPACE, evaluate_space(pos, ei) + , evaluate_space(pos, ei)); Trace::add(TOTAL, score); } @@ -897,13 +885,13 @@ std::string Eval::trace(const Position& pos) { void Eval::init() { - const int MaxSlope = 8700; - const int Peak = 1280000; + const int MaxSlope = 322; + const int Peak = 47410; int t = 0; for (int i = 0; i < 400; ++i) { - t = std::min(Peak, std::min(i * i * 27, t + MaxSlope)); - KingDanger[i] = make_score(t / 1000, 0) * Weights[KingSafety]; + t = std::min(Peak, std::min(i * i - 16, t + MaxSlope)); + KingDanger[i] = make_score(t * 268 / 7700, 0); } } diff --git a/src/pawns.cpp b/src/pawns.cpp index 3b0bf250..0642c679 100644 --- a/src/pawns.cpp +++ b/src/pawns.cpp @@ -34,30 +34,30 @@ namespace { // Isolated pawn penalty by opposed flag and file const Score Isolated[2][FILE_NB] = { - { S(37, 45), S(54, 52), S(60, 52), S(60, 52), - S(60, 52), S(60, 52), S(54, 52), S(37, 45) }, - { S(25, 30), S(36, 35), S(40, 35), S(40, 35), - S(40, 35), S(40, 35), S(36, 35), S(25, 30) } }; + { S(31, 36), S(45, 41), S(50, 41), S(50, 41), + S(50, 41), S(50, 41), S(45, 41), S(31, 36) }, + { S(21, 24), S(30, 28), S(33, 28), S(33, 28), + S(33, 28), S(33, 28), S(30, 28), S(21, 24) } }; // Backward pawn penalty by opposed flag - const Score Backward[2] = { S(67, 42), S(49, 24) }; + const Score Backward[2] = { S(56, 33), S(41, 19) }; // Unsupported pawn penalty for pawns which are neither isolated or backward, // by number of pawns it supports [less than 2 / exactly 2]. - const Score Unsupported[2] = { S(20, 10), S(25, 15) }; + const Score Unsupported[2] = { S(17, 8), S(21, 12) }; // Connected pawn bonus by opposed, phalanx, twice supported and rank Score Connected[2][2][2][RANK_NB]; // Doubled pawn penalty by file const Score Doubled[FILE_NB] = { - S(13, 43), S(20, 48), S(23, 48), S(23, 48), - S(23, 48), S(23, 48), S(20, 48), S(13, 43) }; + S(11, 34), S(17, 38), S(19, 38), S(19, 38), + S(19, 38), S(19, 38), S(17, 38), S(11, 34) }; // Lever bonus by rank const Score Lever[RANK_NB] = { S( 0, 0), S( 0, 0), S(0, 0), S(0, 0), - S(20, 20), S(40, 40), S(0, 0), S(0, 0) }; + S(17, 16), S(33, 32), S(0, 0), S(0, 0) }; // Weakness of our pawn shelter in front of the king by [distance from edge][rank] const Value ShelterWeakness[][RANK_NB] = { @@ -204,7 +204,7 @@ namespace Pawns { void init() { - static const int Seed[RANK_NB] = { 0, 6, 15, 10, 57, 75, 135, 258 }; + static const int Seed[RANK_NB] = { 0, 8, 19, 13, 71, 94, 169, 324 }; for (int opposed = 0; opposed <= 1; ++opposed) for (int phalanx = 0; phalanx <= 1; ++phalanx) @@ -213,7 +213,7 @@ void init() { int v = (Seed[r] + (phalanx ? (Seed[r + 1] - Seed[r]) / 2 : 0)) >> opposed; v += (apex ? v / 2 : 0); - Connected[opposed][phalanx][apex][r] = make_score(3 * v / 2, v); + Connected[opposed][phalanx][apex][r] = make_score(v, v * 5 / 8); } }