WebSVN – Games.Chess Giants – Diff – //engine-stockfish/evaluate.cpp

 #include <cassert>
 #include <cstring>   // For std::memset
 #include <iomanip>
 #include <sstream>
-#include "bitcount.h"
+#include "bitboard.h"
 #include "evaluate.h"
 #include "material.h"
 #include "pawns.h"
 namespace {
   struct EvalInfo {
     // attackedBy[color][piece type] is a bitboard representing all squares
     // attacked by a given color and piece type (can be also ALL_PIECES).
     Bitboard attackedBy[COLOR_NB][PIECE_TYPE_NB];
+    // attackedBy2[color] are the squares attacked by 2 pieces of a given color,
+    // possibly via x-ray or by one pawn and one piece. Diagonal x-ray through
+    // pawn or squares attacked by 2 pawns are not explicitly added.
+    Bitboard attackedBy2[COLOR_NB];
     // kingRing[color] is the zone around the king which is considered
     // by the king safety evaluation. This consists of the squares directly
     // adjacent to the king, and the three (or two, for a king on an edge file)
     // squares two ranks in front of the king. For instance, if black's king
   // MobilityBonus[PieceType][attacked] contains bonuses for middle and end
   // game, indexed by piece type and number of attacked squares in the MobilityArea.
   const Score MobilityBonus[][32] = {
     {}, {},
-    { S(-75,-76), S(-56,-54), S(- 9,-26), S( -2,-10), S(  6,  5), S( 15, 11), // Knights
+    { S(-75,-76), S(-56,-54), S( -9,-26), S( -2,-10), S(  6,  5), S( 15, 11), // Knights
       S( 22, 26), S( 30, 28), S( 36, 29) },
     { S(-48,-58), S(-21,-19), S( 16, -2), S( 26, 12), S( 37, 22), S( 51, 42), // Bishops
       S( 54, 54), S( 63, 58), S( 65, 63), S( 71, 70), S( 79, 74), S( 81, 86),
       S( 92, 90), S( 97, 94) },
     { S(-56,-78), S(-25,-18), S(-11, 26), S( -5, 55), S( -4, 70), S( -1, 81), // Rooks
   };
   // Outpost[knight/bishop][supported by pawn] contains bonuses for knights and
   // bishops outposts, bigger if outpost piece is supported by a pawn.
   const Score Outpost[][2] = {
-    { S(42,11), S(63,17) }, // Knights
+    { S(43,11), S(65,20) }, // Knights
-    { S(18, 5), S(27, 8) }  // Bishops
+    { S(20, 3), S(29, 8) }  // Bishops
   };
   // ReachableOutpost[knight/bishop][supported by pawn] contains bonuses for
   // knights and bishops which can reach an outpost square in one move, bigger
   // if outpost square is supported by a pawn.
   const Score ReachableOutpost[][2] = {
-    { S(21, 5), S(31, 8) }, // Knights
+    { S(21, 5), S(35, 8) }, // Knights
-    { S( 8, 2), S(13, 4) }  // Bishops
+    { S( 8, 0), S(14, 4) }  // Bishops
   };
   // RookOnFile[semiopen/open] contains bonuses for each rook when there is no
   // friendly pawn on the rook file.
-  const Score RookOnFile[2] = { S(19, 10), S(43, 21) };
+  const Score RookOnFile[2] = { S(20, 7), S(45, 20) };
   // ThreatBySafePawn[PieceType] contains bonuses according to which piece
   // type is attacked by a pawn which is protected or is not attacked.
   const Score ThreatBySafePawn[PIECE_TYPE_NB] = {
-    S(0, 0), S(0, 0), S(176, 139), S(131, 127), S(217, 218), S(203, 215) };
+    S(0, 0), S(0, 0), S(176, 139), S(131, 127), S(217, 218), S(203, 215)
+  };
   // Threat[by minor/by rook][attacked PieceType] contains
   // bonuses according to which piece type attacks which one.
   // Attacks on lesser pieces which are pawn-defended are not considered.
   const Score Threat[][PIECE_TYPE_NB] = {
   const Score ThreatByKing[2] = { S(3, 62), S(9, 138) };
   // 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(26), V(68), V(161), V(247) },
+    { V(5), V( 5), V(31), V(73), V(166), V(252) },
-    { V(7), V(14), V(38), V(64), V(137), V(193) }
+    { V(7), V(14), V(38), V(73), V(166), V(252) }
   };
   // PassedFile[File] contains a bonus according to the file of a passed pawn
   const Score PassedFile[FILE_NB] = {
     S(  9, 10), S( 2, 10), S( 1, -8), S(-20,-12),
   };
   // Assorted bonuses and penalties used by evaluation
   const Score MinorBehindPawn     = S(16,  0);
   const Score BishopPawns         = S( 8, 12);
-  const Score RookOnPawn          = S( 7, 27);
+  const Score RookOnPawn          = S( 8, 24);
   const Score TrappedRook         = S(92,  0);
+  const Score CloseEnemies        = S( 7,  0);
-  const Score Checked             = S(20, 20);
+  const Score SafeCheck           = S(20, 20);
+  const Score OtherCheck          = S(10, 10);
-  const Score ThreatByHangingPawn = S(70, 63);
+  const Score ThreatByHangingPawn = S(71, 61);
+  const Score LooseEnemies        = S( 0, 25);
+  const Score WeakQueen           = S(35,  0);
-  const Score Hanging             = S(48, 28);
+  const Score Hanging             = S(48, 27);
-  const Score ThreatByPawnPush    = S(31, 19);
+  const Score ThreatByPawnPush    = S(38, 22);
   const Score Unstoppable         = S( 0, 20);
+  const Score PawnlessFlank       = S(20, 80);
+  const Score HinderPassedPawn    = S( 7,  0);
   // Penalty for a bishop on a1/h1 (a8/h8 for black) which is trapped by
   // a friendly pawn on b2/g2 (b7/g7 for black). This can obviously only
   // happen in Chess960 games.
   const Score TrappedBishopA1H1 = S(50, 50);
   #undef S
   #undef V
-  // King danger constants and variables. The king danger scores are looked-up
-  // in KingDanger[]. Various little "meta-bonuses" measuring the strength
-  // of the enemy attack are added up into an integer, which is used as an
-  // index to KingDanger[].
-  Score KingDanger[512];
   // KingAttackWeights[PieceType] contains king attack weights by piece type
-  const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 7, 5, 4, 1 };
+  const int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 78, 56, 45, 11 };
   // Penalties for enemy's safe checks
-  const int QueenContactCheck = 89;
+  const int QueenContactCheck = 997;
-  const int QueenCheck        = 50;
+  const int QueenCheck        = 695;
-  const int RookCheck         = 45;
+  const int RookCheck         = 638;
-  const int BishopCheck       = 6;
+  const int BishopCheck       = 538;
-  const int KnightCheck       = 14;
+  const int KnightCheck       = 874;
   // eval_init() initializes king and attack bitboards for a given color
   // adding pawn attacks. To be done at the beginning of the evaluation.
   template<Color Us>
   void eval_init(const Position& pos, EvalInfo& ei) {
-    const Color  Them = (Us == WHITE ? BLACK   : WHITE);
+    const Color  Them = (Us == WHITE ? BLACK : WHITE);
-    const Square Down = (Us == WHITE ? DELTA_S : DELTA_N);
+    const Square Down = (Us == WHITE ? SOUTH : NORTH);
     ei.pinnedPieces[Us] = pos.pinned_pieces(Us);
-    Bitboard b = ei.attackedBy[Them][KING] = pos.attacks_from<KING>(pos.square<KING>(Them));
+    Bitboard b = ei.attackedBy[Them][KING];
     ei.attackedBy[Them][ALL_PIECES] |= b;
     ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][PAWN] = ei.pi->pawn_attacks(Us);
+    ei.attackedBy2[Us] = ei.attackedBy[Us][PAWN] & ei.attackedBy[Us][KING];
     // Init king safety tables only if we are going to use them
     if (pos.non_pawn_material(Us) >= QueenValueMg)
+    {
-        ei.kingRing[Them] = b | shift_bb<Down>(b);
+        ei.kingRing[Them] = b | shift<Down>(b);
         b &= ei.attackedBy[Us][PAWN];
-        ei.kingAttackersCount[Us] = b ? popcount<Max15>(b) : 0;
+        ei.kingAttackersCount[Us] = popcount(b);
         ei.kingAdjacentZoneAttacksCount[Us] = ei.kingAttackersWeight[Us] = 0;
+    }
     else
         ei.kingRing[Them] = ei.kingAttackersCount[Us] = 0;
+  }
                          : pos.attacks_from<Pt>(s);
         if (ei.pinnedPieces[Us] & s)
             b &= LineBB[pos.square<KING>(Us)][s];
+        ei.attackedBy2[Us] |= ei.attackedBy[Us][ALL_PIECES] & b;
         ei.attackedBy[Us][ALL_PIECES] |= ei.attackedBy[Us][Pt] |= b;
         if (b & ei.kingRing[Them])
+        {
             ei.kingAttackersCount[Us]++;
             ei.kingAttackersWeight[Us] += KingAttackWeights[Pt];
-            bb = b & ei.attackedBy[Them][KING];
-            if (bb)
-                ei.kingAdjacentZoneAttacksCount[Us] += popcount<Max15>(bb);
+            ei.kingAdjacentZoneAttacksCount[Us] += popcount(b & ei.attackedBy[Them][KING]);
+        }
         if (Pt == QUEEN)
             b &= ~(  ei.attackedBy[Them][KNIGHT]
                    | ei.attackedBy[Them][BISHOP]
                    | ei.attackedBy[Them][ROOK]);
-        int mob = popcount<Pt == QUEEN ? Full : Max15>(b & mobilityArea[Us]);
+        int mob = popcount(b & mobilityArea[Us]);
         mobility[Us] += MobilityBonus[Pt][mob];
         if (Pt == BISHOP || Pt == KNIGHT)
+        {
             // when that pawn is also blocked.
             if (   Pt == BISHOP
                 && pos.is_chess960()
                 && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1)))
+            {
-                Square d = pawn_push(Us) + (file_of(s) == FILE_A ? DELTA_E : DELTA_W);
+                Square d = pawn_push(Us) + (file_of(s) == FILE_A ? EAST : WEST);
                 if (pos.piece_on(s + d) == make_piece(Us, PAWN))
                     score -= !pos.empty(s + d + pawn_push(Us))                ? TrappedBishopA1H1 * 4
                             : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? TrappedBishopA1H1 * 2
                                                                               : TrappedBishopA1H1;
+            }
         if (Pt == ROOK)
+        {
             // Bonus for aligning with enemy pawns on the same rank/file
             if (relative_rank(Us, s) >= RANK_5)
-            {
-                Bitboard alignedPawns = pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s];
+                score += RookOnPawn * popcount(pos.pieces(Them, PAWN) & PseudoAttacks[ROOK][s]);
-                if (alignedPawns)
-                    score += RookOnPawn * popcount<Max15>(alignedPawns);
-            }
             // Bonus when on an open or semi-open file
             if (ei.pi->semiopen_file(Us, file_of(s)))
                 score += RookOnFile[!!ei.pi->semiopen_file(Them, file_of(s))];
                 if (   ((file_of(ksq) < FILE_E) == (file_of(s) < file_of(ksq)))
                     && (rank_of(ksq) == rank_of(s) || relative_rank(Us, ksq) == RANK_1)
                     && !ei.pi->semiopen_side(Us, file_of(ksq), file_of(s) < file_of(ksq)))
                     score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.can_castle(Us));
+            }
+        }
+        if (Pt == QUEEN)
+        {
+            // Penalty if any relative pin or discovered attack against the queen
+            Bitboard pinners;
+            if (pos.slider_blockers(pos.pieces(Them, ROOK, BISHOP), s, pinners))
+                score -= WeakQueen;
+        }
+    }
     if (DoTrace)
         Trace::add(Pt, Us, score);
   template<>
   Score evaluate_pieces< true, WHITE, KING>(const Position&, EvalInfo&, Score*, const Bitboard*) { return SCORE_ZERO; }
   // evaluate_king() assigns bonuses and penalties to a king of a given color
+  const Bitboard WhiteCamp = Rank1BB | Rank2BB | Rank3BB | Rank4BB | Rank5BB;
+  const Bitboard BlackCamp = Rank8BB | Rank7BB | Rank6BB | Rank5BB | Rank4BB;
+  const Bitboard QueenSide   = FileABB | FileBBB | FileCBB | FileDBB;
+  const Bitboard CenterFiles = FileCBB | FileDBB | FileEBB | FileFBB;
+  const Bitboard KingSide    = FileEBB | FileFBB | FileGBB | FileHBB;
+  const Bitboard KingFlank[COLOR_NB][FILE_NB] = {
+    { QueenSide   & WhiteCamp, QueenSide & WhiteCamp, QueenSide & WhiteCamp, CenterFiles & WhiteCamp,
+      CenterFiles & WhiteCamp, KingSide  & WhiteCamp, KingSide  & WhiteCamp, KingSide    & WhiteCamp },
+    { QueenSide   & BlackCamp, QueenSide & BlackCamp, QueenSide & BlackCamp, CenterFiles & BlackCamp,
+      CenterFiles & BlackCamp, KingSide  & BlackCamp, KingSide  & BlackCamp, KingSide    & BlackCamp },
+  };
   template<Color Us, bool DoTrace>
   Score evaluate_king(const Position& pos, const EvalInfo& ei) {
     const Color Them = (Us == WHITE ? BLACK : WHITE);
+    const Square  Up = (Us == WHITE ? NORTH : SOUTH);
-    Bitboard undefended, b, b1, b2, safe;
+    Bitboard undefended, b, b1, b2, safe, other;
-    int attackUnits;
+    int kingDanger;
     const Square ksq = pos.square<KING>(Us);
     // King shelter and enemy pawns storm
     Score score = ei.pi->king_safety<Us>(pos, ksq);
     // Main king safety evaluation
     if (ei.kingAttackersCount[Them])
+    {
-        // Find the attacked squares around the king which have no defenders
+        // Find the attacked squares which are defended only by the king...
-        // apart from the king itself.
-        undefended =  ei.attackedBy[Them][ALL_PIECES]
+        undefended =   ei.attackedBy[Them][ALL_PIECES]
-                    & ei.attackedBy[Us][KING]
+                    &  ei.attackedBy[Us][KING]
-                    & ~(  ei.attackedBy[Us][PAWN]   | ei.attackedBy[Us][KNIGHT]
-                        | ei.attackedBy[Us][BISHOP] | ei.attackedBy[Us][ROOK]
-                        | ei.attackedBy[Us][QUEEN]);
+                    & ~ei.attackedBy2[Us];
+        // ... and those which are not defended at all in the larger king ring
+        b =  ei.attackedBy[Them][ALL_PIECES] & ~ei.attackedBy[Us][ALL_PIECES]
+           & ei.kingRing[Us] & ~pos.pieces(Them);
-        // Initialize the 'attackUnits' variable, which is used later on as an
+        // Initialize the 'kingDanger' variable, which will be transformed
-        // index into the KingDanger[] array. The initial value is based on the
+        // later into a king danger score. The initial value is based on the
         // number and types of the enemy's attacking pieces, the number of
         // attacked and undefended squares around our king and the quality of
         // the pawn shelter (current 'score' value).
-        attackUnits =  std::min(72, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them])
+        kingDanger =  std::min(807, ei.kingAttackersCount[Them] * ei.kingAttackersWeight[Them])
-                     +  9 * ei.kingAdjacentZoneAttacksCount[Them]
+                    + 101 * ei.kingAdjacentZoneAttacksCount[Them]
-                     + 27 * popcount<Max15>(undefended)
+                    + 235 * popcount(undefended)
-                     + 11 * !!ei.pinnedPieces[Us]
+                    + 134 * (popcount(b) + !!ei.pinnedPieces[Us])
-                     - 64 * !pos.count<QUEEN>(Them)
+                    - 717 * !pos.count<QUEEN>(Them)
-                     - mg_value(score) / 8;
+                    -   7 * mg_value(score) / 5 - 5;
         // Analyse the enemy's safe queen contact checks. Firstly, find the
         // undefended squares around the king reachable by the enemy queen...
         b = undefended & ei.attackedBy[Them][QUEEN] & ~pos.pieces(Them);
-        if (b)
-        {
-            // ...and then remove squares not supported by another enemy piece
-            b &=  ei.attackedBy[Them][PAWN]   | ei.attackedBy[Them][KNIGHT]
-                | ei.attackedBy[Them][BISHOP] | ei.attackedBy[Them][ROOK]
-                | ei.attackedBy[Them][KING];
-            if (b)
+        // ...and keep squares supported by another enemy piece
-                attackUnits += QueenContactCheck * popcount<Max15>(b);
+        kingDanger += QueenContactCheck * popcount(b & ei.attackedBy2[Them]);
-        }
-        // Analyse the enemy's safe distance checks for sliders and knights
+        // Analyse the safe enemy's checks which are possible on next move...
-        safe = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them));
+        safe  = ~(ei.attackedBy[Us][ALL_PIECES] | pos.pieces(Them));
+        // ... and some other potential checks, only requiring the square to be
+        // safe from pawn-attacks, and not being occupied by a blocked pawn.
+        other = ~(   ei.attackedBy[Us][PAWN]
+                  | (pos.pieces(Them, PAWN) & shift<Up>(pos.pieces(PAWN))));
-        b1 = pos.attacks_from<ROOK  >(ksq) & safe;
+        b1 = pos.attacks_from<ROOK  >(ksq);
-        b2 = pos.attacks_from<BISHOP>(ksq) & safe;
+        b2 = pos.attacks_from<BISHOP>(ksq);
         // Enemy queen safe checks
-        b = (b1 | b2) & ei.attackedBy[Them][QUEEN];
+        if ((b1 | b2) & ei.attackedBy[Them][QUEEN] & safe)
-        if (b)
-        {
-            attackUnits += QueenCheck * popcount<Max15>(b);
+            kingDanger += QueenCheck, score -= SafeCheck;
-            score -= Checked;
-        }
+        // For other pieces, also consider the square safe if attacked twice,
-        // Enemy rooks safe checks
+        // and only defended by a queen.
-        b = b1 & ei.attackedBy[Them][ROOK];
+        safe |=  ei.attackedBy2[Them]
-        if (b)
-        {
-            attackUnits += RookCheck * popcount<Max15>(b);
+               & ~(ei.attackedBy2[Us] | pos.pieces(Them))
-            score -= Checked;
+               & ei.attackedBy[Us][QUEEN];
-        }
-        // Enemy bishops safe checks
+        // Enemy rooks safe and other checks
-        b = b2 & ei.attackedBy[Them][BISHOP];
+        if (b1 & ei.attackedBy[Them][ROOK] & safe)
-        if (b)
-        {
-            attackUnits += BishopCheck * popcount<Max15>(b);
+            kingDanger += RookCheck, score -= SafeCheck;
-            score -= Checked;
-        }
-        // Enemy knights safe checks
-        b = pos.attacks_from<KNIGHT>(ksq) & ei.attackedBy[Them][KNIGHT] & safe;
+        else if (b1 & ei.attackedBy[Them][ROOK] & other)
-        if (b)
-        {
-            attackUnits += KnightCheck * popcount<Max15>(b);
-            score -= Checked;
+            score -= OtherCheck;
-        }
+        // Enemy bishops safe and other checks
+        if (b2 & ei.attackedBy[Them][BISHOP] & safe)
-        // Finally, extract the king danger score from the KingDanger[]
+            kingDanger += BishopCheck, score -= SafeCheck;
+        else if (b2 & ei.attackedBy[Them][BISHOP] & other)
+            score -= OtherCheck;
+        // Enemy knights safe and other checks
+        b = pos.attacks_from<KNIGHT>(ksq) & ei.attackedBy[Them][KNIGHT];
+        if (b & safe)
+            kingDanger += KnightCheck, score -= SafeCheck;
+        else if (b & other)
+            score -= OtherCheck;
-        // array and subtract the score from the evaluation.
+        // Compute the king danger score and subtract it from the evaluation
+        if (kingDanger > 0)
-        score -= KingDanger[std::max(std::min(attackUnits, 399), 0)];
+            score -= make_score(std::min(kingDanger * kingDanger / 4096,  2 * int(BishopValueMg)), 0);
+    }
+    // King tropism: firstly, find squares that opponent attacks in our king flank
+    File kf = file_of(ksq);
+    b = ei.attackedBy[Them][ALL_PIECES] & KingFlank[Us][kf];
+    assert(((Us == WHITE ? b << 4 : b >> 4) & b) == 0);
+    assert(popcount(Us == WHITE ? b << 4 : b >> 4) == popcount(b));
+    // Secondly, add the squares which are attacked twice in that flank and
+    // which are not defended by our pawns.
+    b =  (Us == WHITE ? b << 4 : b >> 4)
+       | (b & ei.attackedBy2[Them] & ~ei.attackedBy[Us][PAWN]);
+    score -= CloseEnemies * popcount(b);
+    // Penalty when our king is on a pawnless flank
+    if (!(pos.pieces(PAWN) & (KingFlank[WHITE][kf] | KingFlank[BLACK][kf])))
+        score -= PawnlessFlank;
     if (DoTrace)
         Trace::add(KING, Us, score);
     return score;
+  }
   // evaluate_threats() assigns bonuses according to the types of the attacking
   // and the attacked pieces.
   template<Color Us, bool DoTrace>
   Score evaluate_threats(const Position& pos, const EvalInfo& ei) {
-    const Color Them        = (Us == WHITE ? BLACK    : WHITE);
+    const Color Them        = (Us == WHITE ? BLACK      : WHITE);
-    const Square Up         = (Us == WHITE ? DELTA_N  : DELTA_S);
+    const Square Up         = (Us == WHITE ? NORTH      : SOUTH);
-    const Square Left       = (Us == WHITE ? DELTA_NW : DELTA_SE);
+    const Square Left       = (Us == WHITE ? NORTH_WEST : SOUTH_EAST);
-    const Square Right      = (Us == WHITE ? DELTA_NE : DELTA_SW);
+    const Square Right      = (Us == WHITE ? NORTH_EAST : SOUTH_WEST);
-    const Bitboard TRank2BB = (Us == WHITE ? Rank2BB  : Rank7BB);
+    const Bitboard TRank2BB = (Us == WHITE ? Rank2BB    : Rank7BB);
-    const Bitboard TRank7BB = (Us == WHITE ? Rank7BB  : Rank2BB);
+    const Bitboard TRank7BB = (Us == WHITE ? Rank7BB    : Rank2BB);
     enum { Minor, Rook };
     Bitboard b, weak, defended, safeThreats;
     Score score = SCORE_ZERO;
+    // Small bonus if the opponent has loose pawns or pieces
+    if (   (pos.pieces(Them) ^ pos.pieces(Them, QUEEN, KING))
+        & ~(ei.attackedBy[Us][ALL_PIECES] | ei.attackedBy[Them][ALL_PIECES]))
+        score += LooseEnemies;
     // Non-pawn enemies attacked by a pawn
     weak = (pos.pieces(Them) ^ pos.pieces(Them, PAWN)) & ei.attackedBy[Us][PAWN];
     if (weak)
+    {
         b = pos.pieces(Us, PAWN) & ( ~ei.attackedBy[Them][ALL_PIECES]
                                     | ei.attackedBy[Us][ALL_PIECES]);
-        safeThreats = (shift_bb<Right>(b) | shift_bb<Left>(b)) & weak;
+        safeThreats = (shift<Right>(b) | shift<Left>(b)) & weak;
         if (weak ^ safeThreats)
             score += ThreatByHangingPawn;
         while (safeThreats)
         b = (pos.pieces(Them, QUEEN) | weak) & ei.attackedBy[Us][ROOK];
         while (b)
             score += Threat[Rook ][type_of(pos.piece_on(pop_lsb(&b)))];
-        b = weak & ~ei.attackedBy[Them][ALL_PIECES];
+        score += Hanging * popcount(weak & ~ei.attackedBy[Them][ALL_PIECES]);
-        if (b)
-            score += Hanging * popcount<Max15>(b);
         b = weak & ei.attackedBy[Us][KING];
         if (b)
             score += ThreatByKing[more_than_one(b)];
+    }
     // Bonus if some pawns can safely push and attack an enemy piece
     b = pos.pieces(Us, PAWN) & ~TRank7BB;
-    b = shift_bb<Up>(b | (shift_bb<Up>(b & TRank2BB) & ~pos.pieces()));
+    b = shift<Up>(b | (shift<Up>(b & TRank2BB) & ~pos.pieces()));
     b &=  ~pos.pieces()
         & ~ei.attackedBy[Them][PAWN]
         & (ei.attackedBy[Us][ALL_PIECES] | ~ei.attackedBy[Them][ALL_PIECES]);
-    b =  (shift_bb<Left>(b) | shift_bb<Right>(b))
+    b =  (shift<Left>(b) | shift<Right>(b))
        &  pos.pieces(Them)
        & ~ei.attackedBy[Us][PAWN];
-    if (b)
-        score += ThreatByPawnPush * popcount<Max15>(b);
+    score += ThreatByPawnPush * popcount(b);
     if (DoTrace)
         Trace::add(THREAT, Us, score);
     return score;
   template<Color Us, bool DoTrace>
   Score evaluate_passed_pawns(const Position& pos, const EvalInfo& ei) {
     const Color Them = (Us == WHITE ? BLACK : WHITE);
-    Bitboard b, squaresToQueen, defendedSquares, unsafeSquares;
+    Bitboard b, bb, squaresToQueen, defendedSquares, unsafeSquares;
     Score score = SCORE_ZERO;
     b = ei.pi->passed_pawns(Us);
     while (b)
+    {
         Square s = pop_lsb(&b);
         assert(pos.pawn_passed(Us, s));
+        assert(!(pos.pieces(PAWN) & forward_bb(Us, s)));
+        bb = forward_bb(Us, s) & (ei.attackedBy[Them][ALL_PIECES] | pos.pieces(Them));
+        score -= HinderPassedPawn * popcount(bb);
         int r = relative_rank(Us, s) - RANK_2;
         int rr = r * (r - 1);
         Value mbonus = Passed[MG][r], ebonus = Passed[EG][r];
                 // If there is a rook or queen attacking/defending the pawn from behind,
                 // consider all the squaresToQueen. Otherwise consider only the squares
                 // in the pawn's path attacked or occupied by the enemy.
                 defendedSquares = unsafeSquares = squaresToQueen = forward_bb(Us, s);
-                Bitboard bb = forward_bb(Them, s) & pos.pieces(ROOK, QUEEN) & pos.attacks_from<ROOK>(s);
+                bb = forward_bb(Them, s) & pos.pieces(ROOK, QUEEN) & pos.attacks_from<ROOK>(s);
                 if (!(pos.pieces(Us) & bb))
                     defendedSquares &= ei.attackedBy[Us][ALL_PIECES];
                 if (!(pos.pieces(Them) & bb))
                     k += 6;
                 else if (defendedSquares & blockSq)
                     k += 4;
-                mbonus += k * rr * 3 / 4, ebonus += k * rr;
+                mbonus += k * rr, ebonus += k * rr;
+            }
             else if (pos.pieces(Us) & blockSq)
-                mbonus += (rr * 3 + r * 2 + 3) * 3 / 4, ebonus += rr + r * 2;
+                mbonus += rr + r * 2, ebonus += rr + r * 2;
         } // rr != 0
-        if (pos.count<PAWN>(Us) < pos.count<PAWN>(Them))
-            ebonus += ebonus / 4;
         score += make_score(mbonus, ebonus) + PassedFile[file_of(s)];
+    }
     if (DoTrace)
     // Since SpaceMask[Us] is fully on our half of the board...
     assert(unsigned(safe >> (Us == WHITE ? 32 : 0)) == 0);
     // ...count safe + (behind & safe) with a single popcount
-    int bonus = popcount<Full>((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe));
+    int bonus = popcount((Us == WHITE ? safe << 32 : safe >> 32) | (behind & safe));
-    int weight =  pos.count<KNIGHT>(Us) + pos.count<BISHOP>(Us)
+    bonus = std::min(16, bonus);
-                + pos.count<KNIGHT>(Them) + pos.count<BISHOP>(Them);
+    int weight = pos.count<ALL_PIECES>(Us) - 2 * ei.pi->open_files();
-    return make_score(bonus * weight * weight * 2 / 11, 0);
+    return make_score(bonus * weight * weight / 18, 0);
+  }
   // evaluate_initiative() computes the initiative correction value for the
   // position, i.e., second order bonus/malus based on the known attacking/defending
   // status of the players.
   Score evaluate_initiative(const Position& pos, int asymmetry, Value eg) {
-    int kingDistance = distance<File>(pos.square<KING>(WHITE), pos.square<KING>(BLACK));
+    int kingDistance =  distance<File>(pos.square<KING>(WHITE), pos.square<KING>(BLACK))
+                      - distance<Rank>(pos.square<KING>(WHITE), pos.square<KING>(BLACK));
     int pawns = pos.count<PAWN>(WHITE) + pos.count<PAWN>(BLACK);
     // Compute the initiative bonus for the attacking side
-    int initiative = 8 * (pawns + asymmetry + kingDistance - 15);
+    int initiative = 8 * (asymmetry + kingDistance - 15) + 12 * pawns;
     // Now apply the bonus: note that we find the attacking side by extracting
     // the sign of the endgame value, and that we carefully cap the bonus so
     // that the endgame score will never be divided by more than two.
     int value = ((eg > 0) - (eg < 0)) * std::max(initiative, -abs(eg / 2));
     return make_score(0, value);
+  }
   // evaluate_scale_factor() computes the scale factor for the winning side
-  ScaleFactor evaluate_scale_factor(const Position& pos, const EvalInfo& ei, Score score) {
+  ScaleFactor evaluate_scale_factor(const Position& pos, const EvalInfo& ei, Value eg) {
-    Color strongSide = eg_value(score) > VALUE_DRAW ? WHITE : BLACK;
+    Color strongSide = eg > VALUE_DRAW ? WHITE : BLACK;
     ScaleFactor sf = ei.me->scale_factor(pos, strongSide);
     // If we don't already have an unusual scale factor, check for certain
     // types of endgames, and use a lower scale for those.
     if (    ei.me->game_phase() < PHASE_MIDGAME
                 sf = more_than_one(pos.pieces(PAWN)) ? ScaleFactor(31) : ScaleFactor(9);
             // Endgame with opposite-colored bishops, but also other pieces. Still
             // a bit drawish, but not as drawish as with only the two bishops.
             else
-                sf = ScaleFactor(46 * sf / SCALE_FACTOR_NORMAL);
+                sf = ScaleFactor(46);
+        }
         // Endings where weaker side can place his king in front of the opponent's
         // pawns are drawish.
-        else if (    abs(eg_value(score)) <= BishopValueEg
+        else if (    abs(eg) <= BishopValueEg
-                 &&  ei.pi->pawn_span(strongSide) <= 1
+                 &&  pos.count<PAWN>(strongSide) <= 2
                  && !pos.pawn_passed(~strongSide, pos.square<KING>(~strongSide)))
-            sf = ei.pi->pawn_span(strongSide) ? ScaleFactor(51) : ScaleFactor(37);
+            sf = ScaleFactor(37 + 7 * pos.count<PAWN>(strongSide));
+    }
     return sf;
+  }
 template<bool DoTrace>
 Value Eval::evaluate(const Position& pos) {
   assert(!pos.checkers());
+  Score mobility[COLOR_NB] = { SCORE_ZERO, SCORE_ZERO };
   EvalInfo ei;
-  Score score, mobility[COLOR_NB] = { SCORE_ZERO, SCORE_ZERO };
-  // Initialize score by reading the incrementally updated scores included in
-  // the position object (material + piece square tables). Score is computed
-  // internally from the white point of view.
-  score = pos.psq_score();
   // Probe the material hash table
   ei.me = Material::probe(pos);
-  score += ei.me->imbalance();
   // If we have a specialized evaluation function for the current material
   // configuration, call it and return.
   if (ei.me->specialized_eval_exists())
       return ei.me->evaluate(pos);
+  // Initialize score by reading the incrementally updated scores included in
+  // the position object (material + piece square tables) and the material
+  // imbalance. Score is computed internally from the white point of view.
+  Score score = pos.psq_score() + ei.me->imbalance();
   // Probe the pawn hash table
   ei.pi = Pawns::probe(pos);
   score += ei.pi->pawns_score();
   // Initialize attack and king safety bitboards
   ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0;
+  ei.attackedBy[WHITE][KING] = pos.attacks_from<KING>(pos.square<KING>(WHITE));
+  ei.attackedBy[BLACK][KING] = pos.attacks_from<KING>(pos.square<KING>(BLACK));
   eval_init<WHITE>(pos, ei);
   eval_init<BLACK>(pos, ei);
   // Pawns blocked or on ranks 2 and 3 will be excluded from the mobility area
   Bitboard blockedPawns[] = {
-    pos.pieces(WHITE, PAWN) & (shift_bb<DELTA_S>(pos.pieces()) | Rank2BB | Rank3BB),
+    pos.pieces(WHITE, PAWN) & (shift<SOUTH>(pos.pieces()) | Rank2BB | Rank3BB),
-    pos.pieces(BLACK, PAWN) & (shift_bb<DELTA_N>(pos.pieces()) | Rank7BB | Rank6BB)
+    pos.pieces(BLACK, PAWN) & (shift<NORTH>(pos.pieces()) | Rank7BB | Rank6BB)
   };
   // Do not include in mobility area squares protected by enemy pawns, or occupied
   // by our blocked pawns or king.
   Bitboard mobilityArea[] = {
   // Evaluate position potential for the winning side
   score += evaluate_initiative(pos, ei.pi->pawn_asymmetry(), eg_value(score));
   // Evaluate scale factor for the winning side
-  ScaleFactor sf = evaluate_scale_factor(pos, ei, score);
+  ScaleFactor sf = evaluate_scale_factor(pos, ei, eg_value(score));
   // Interpolate between a middlegame and a (scaled by 'sf') endgame score
   Value v =  mg_value(score) * int(ei.me->game_phase())
            + eg_value(score) * int(PHASE_MIDGAME - ei.me->game_phase()) * sf / SCALE_FACTOR_NORMAL;
      << "          Total | " << Term(TOTAL);
   ss << "\nTotal Evaluation: " << to_cp(v) << " (white side)\n";
   return ss.str();
-}
-/// init() computes evaluation weights, usually at startup
-void Eval::init() {
-  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 - 16, t + MaxSlope));
-      KingDanger[i] = make_score(t * 268 / 7700, 0);
-  }
+}

Subversion Repositories Games.Chess Giants

Games.Chess Giants//engine-stockfish/evaluate.cpp – Rev 96 → 154