From 48c95706c857152c72c01e144875b88ce177a4ff Mon Sep 17 00:00:00 2001 From: Marco Costalba Date: Sat, 9 May 2009 22:21:26 +0100 Subject: [PATCH] Split evaluate_outposts from evaluate_common This is an old patch, was part of a series, but is good also alone as a cleanup. No functional change. Signed-off-by: Marco Costalba --- src/evaluate.cpp | 78 +++++++++++++++++++++++++----------------------- 1 file changed, 41 insertions(+), 37 deletions(-) diff --git a/src/evaluate.cpp b/src/evaluate.cpp index 372313b7..62860b4a 100644 --- a/src/evaluate.cpp +++ b/src/evaluate.cpp @@ -538,22 +538,19 @@ void read_weights(Color us) { namespace { - // evaluate_common() computes terms common to all pieces attack + // evaluate_mobility() computes mobility and attacks for every piece template - int evaluate_common(const Position& p, const Bitboard& b, Color us, EvalInfo& ei, Square s = SQ_NONE) { + int evaluate_mobility(const Position& p, const Bitboard& b, Color us, Color them, EvalInfo& ei) { static const int AttackWeight[] = { 0, 0, KnightAttackWeight, BishopAttackWeight, RookAttackWeight, QueenAttackWeight }; static const Value* MgBonus[] = { 0, 0, MidgameKnightMobilityBonus, MidgameBishopMobilityBonus, MidgameRookMobilityBonus, MidgameQueenMobilityBonus }; static const Value* EgBonus[] = { 0, 0, EndgameKnightMobilityBonus, EndgameBishopMobilityBonus, EndgameRookMobilityBonus, EndgameQueenMobilityBonus }; - static const Value* OutpostBonus[] = { 0, 0, KnightOutpostBonus, BishopOutpostBonus, 0, 0 }; - - Color them = opposite_color(us); // Update attack info ei.attackedBy[us][Piece] |= b; - // King attack + // King attacks if (b & ei.kingZone[us]) { ei.kingAttackersCount[us]++; @@ -572,28 +569,31 @@ namespace { ei.mgMobility += Sign[us] * MgBonus[Piece][mob]; ei.egMobility += Sign[us] * EgBonus[Piece][mob]; + return mob; + } - // Bishop and Knight outposts - if ( (Piece == BISHOP || Piece == KNIGHT) // compile time condition - && p.square_is_weak(s, them)) - { - // Initial bonus based on square - Value v, bonus; - v = bonus = OutpostBonus[Piece][relative_square(us, s)]; - // Increase bonus if supported by pawn, especially if the opponent has - // no minor piece which can exchange the outpost piece - if (v && (p.pawn_attacks(them, s) & p.pawns(us))) - { - bonus += v / 2; - if ( p.piece_count(them, KNIGHT) == 0 - && (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB) - bonus += v; - } - ei.mgValue += Sign[us] * bonus; - ei.egValue += Sign[us] * bonus; + // evaluate_outposts() evaluates bishop and knight outposts squares + + template + void evaluate_outposts(const Position& p, Color us, Color them, EvalInfo& ei, Square s) { + + // Initial bonus based on square + Value bonus = (Piece == BISHOP ? BishopOutpostBonus[relative_square(us, s)] + : KnightOutpostBonus[relative_square(us, s)]); + + // Increase bonus if supported by pawn, especially if the opponent has + // no minor piece which can exchange the outpost piece + if (bonus && (p.pawn_attacks(them, s) & p.pawns(us))) + { + if ( p.knights(them) == EmptyBoardBB + && (SquaresByColorBB[square_color(s)] & p.bishops(them)) == EmptyBoardBB) + bonus += bonus + bonus / 2; + else + bonus += bonus / 2; } - return mob; + ei.mgValue += Sign[us] * bonus; + ei.egValue += Sign[us] * bonus; } @@ -605,9 +605,9 @@ namespace { Bitboard b; Square s, ksq; - Color them; int mob; File f; + Color them = opposite_color(us); for (int i = 0, e = pos.piece_count(us, Piece); i < e; i++) { @@ -619,9 +619,15 @@ namespace { b = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.queens(us)); else if (Piece == ROOK) b = rook_attacks_bb(s, pos.occupied_squares() & ~pos.rooks_and_queens(us)); + else + assert(false); - // Attacks, mobility and outposts - mob = evaluate_common(pos, b, us, ei, s); + // Attacks and mobility + mob = evaluate_mobility(pos, b, us, them, ei); + + // Bishop and knight outposts squares + if ((Piece == BISHOP || Piece == KNIGHT) && pos.square_is_weak(s, them)) + evaluate_outposts(pos, us, them, ei, s); // Special patterns: trapped bishops on a7/h7/a2/h2 // and trapped bishops on a1/h1/a8/h8 in Chess960. @@ -637,8 +643,6 @@ namespace { if (Piece == ROOK || Piece == QUEEN) { // Queen or rook on 7th rank - them = opposite_color(us); - if ( relative_rank(us, s) == RANK_7 && relative_rank(us, pos.king_square(them)) == RANK_8) { @@ -728,7 +732,7 @@ namespace { ei.mgValue += sign * Value(shelter); } - // King safety. This is quite complicated, and is almost certainly far + // King safety. This is quite complicated, and is almost certainly far // from optimally tuned. Color them = opposite_color(us); @@ -989,7 +993,7 @@ namespace { } } } - // Rook pawns are a special case: They are sometimes worse, and + // Rook pawns are a special case: They are sometimes worse, and // sometimes better than other passed pawns. It is difficult to find // good rules for determining whether they are good or bad. For now, // we try the following: Increase the value for rook pawns if the @@ -997,10 +1001,10 @@ namespace { // value if the other side has a rook or queen. if (square_file(s) == FILE_A || square_file(s) == FILE_H) { - if( pos.non_pawn_material(them) <= KnightValueMidgame - && pos.piece_count(them, KNIGHT) <= 1) + if ( pos.non_pawn_material(them) <= KnightValueMidgame + && pos.piece_count(them, KNIGHT) <= 1) ebonus += ebonus / 4; - else if(pos.rooks_and_queens(them)) + else if (pos.rooks_and_queens(them)) ebonus -= ebonus / 4; } @@ -1012,9 +1016,9 @@ namespace { // Does either side have an unstoppable passed pawn? if (hasUnstoppable[WHITE] && !hasUnstoppable[BLACK]) - ei.egValue += UnstoppablePawnValue - Value(0x40 * movesToGo[WHITE]); + ei.egValue += UnstoppablePawnValue - Value(0x40 * movesToGo[WHITE]); else if (hasUnstoppable[BLACK] && !hasUnstoppable[WHITE]) - ei.egValue -= UnstoppablePawnValue - Value(0x40 * movesToGo[BLACK]); + ei.egValue -= UnstoppablePawnValue - Value(0x40 * movesToGo[BLACK]); else if (hasUnstoppable[BLACK] && hasUnstoppable[WHITE]) { // Both sides have unstoppable pawns! Try to find out who queens -- 2.39.2