Rename piece_attacks() in piece_attacks_from()

It is a bit longer but much easier to understand especially
for people new to the sources. I remember it was not trivial
for me to understand the returned attack bitboard refers to
attacks launched from the given square and not attacking the
given square.

No functional change.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>

diff --git a/src/endgame.cpp b/src/endgame.cpp
index bc9b75eaabb84301abe4b7e344a9577cd20b77ff..94bed094c49f7f043d1c9ede847c825b505bb880 100644 (file)
--- a/src/endgame.cpp
+++ b/src/endgame.cpp
@@ -343,7 +343,7 @@ Value EvaluationFunction<KBBKN>::apply(const Position& pos) {
   result += Value(square_distance(bksq, nsq) * 32);
 
   // Bonus for restricting the knight's mobility
-  result += Value((8 - count_1s_max_15(pos.piece_attacks<KNIGHT>(nsq))) * 8);
+  result += Value((8 - count_1s_max_15(pos.piece_attacks_from<KNIGHT>(nsq))) * 8);
 
   return (strongerSide == pos.side_to_move() ? result : -result);
 }
@@ -434,10 +434,10 @@ ScaleFactor ScalingFunction<KQKRPs>::apply(const Position& pos) {
       && relative_rank(weakerSide, pos.king_square(strongerSide)) >= RANK_4
       && (pos.pieces(ROOK, weakerSide) & relative_rank_bb(weakerSide, RANK_3))
       && (pos.pieces(PAWN, weakerSide) & relative_rank_bb(weakerSide, RANK_2))
-      && (pos.piece_attacks<KING>(kingSq) & pos.pieces(PAWN, weakerSide)))
+      && (pos.piece_attacks_from<KING>(kingSq) & pos.pieces(PAWN, weakerSide)))
   {
       Square rsq = pos.piece_list(weakerSide, ROOK, 0);
-      if (pos.pawn_attacks(rsq, strongerSide) & pos.pieces(PAWN, weakerSide))
+      if (pos.pawn_attacks_from(rsq, strongerSide) & pos.pieces(PAWN, weakerSide))
           return ScaleFactor(0);
   }
   return SCALE_FACTOR_NONE;
@@ -696,7 +696,7 @@ ScaleFactor ScalingFunction<KBPKB>::apply(const Position &pos) {
           Bitboard ray = ray_bb(pawnSq, (strongerSide == WHITE)? SIGNED_DIR_N : SIGNED_DIR_S);
           if (ray & pos.pieces(KING, weakerSide))
               return ScaleFactor(0);
-          if(  (pos.piece_attacks<BISHOP>(weakerBishopSq) & ray)
+          if(  (pos.piece_attacks_from<BISHOP>(weakerBishopSq) & ray)
              && square_distance(weakerBishopSq, pawnSq) >= 3)
               return ScaleFactor(0);
       }
@@ -761,13 +761,13 @@ ScaleFactor ScalingFunction<KBPPKB>::apply(const Position& pos) {
     if (   ksq == blockSq1
         && square_color(ksq) != square_color(wbsq)
         && (   bbsq == blockSq2
-            || (pos.piece_attacks<BISHOP>(blockSq2) & pos.pieces(BISHOP, weakerSide))
+            || (pos.piece_attacks_from<BISHOP>(blockSq2) & pos.pieces(BISHOP, weakerSide))
             || rank_distance(r1, r2) >= 2))
         return ScaleFactor(0);
     else if (   ksq == blockSq2
              && square_color(ksq) != square_color(wbsq)
              && (   bbsq == blockSq1
-                 || (pos.piece_attacks<BISHOP>(blockSq1) & pos.pieces(BISHOP, weakerSide))))
+                 || (pos.piece_attacks_from<BISHOP>(blockSq1) & pos.pieces(BISHOP, weakerSide))))
         return ScaleFactor(0);
     else
         return SCALE_FACTOR_NONE;

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index a105132f0a7a8f6a72eb62df47b013ac23fffc7b..2a4536b7fa43331a38c9497a96fd0c282fe8a970 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -342,8 +342,8 @@ Value do_evaluate(const Position& pos, EvalInfo& ei, int threadID) {
   ei.egValue += apply_weight(ei.pi->eg_value(), WeightPawnStructureEndgame);
 
   // Initialize king attack bitboards and king attack zones for both sides
-  ei.attackedBy[WHITE][KING] = pos.piece_attacks<KING>(pos.king_square(WHITE));
-  ei.attackedBy[BLACK][KING] = pos.piece_attacks<KING>(pos.king_square(BLACK));
+  ei.attackedBy[WHITE][KING] = pos.piece_attacks_from<KING>(pos.king_square(WHITE));
+  ei.attackedBy[BLACK][KING] = pos.piece_attacks_from<KING>(pos.king_square(BLACK));
   ei.kingZone[WHITE] = ei.attackedBy[BLACK][KING] | (ei.attackedBy[BLACK][KING] >> 8);
   ei.kingZone[BLACK] = ei.attackedBy[WHITE][KING] | (ei.attackedBy[WHITE][KING] << 8);
 
@@ -590,7 +590,7 @@ namespace {
 
     // 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(s, them) & p.pieces(PAWN, us)))
+    if (bonus && (p.pawn_attacks_from(s, them) & p.pieces(PAWN, us)))
     {
         if (    p.pieces(KNIGHT, them) == EmptyBoardBB
             && (SquaresByColorBB[square_color(s)] & p.pieces(BISHOP, them)) == EmptyBoardBB)
@@ -620,7 +620,7 @@ namespace {
         s = pos.piece_list(us, Piece, i);
 
         if (Piece == KNIGHT || Piece == QUEEN)
-            b = pos.piece_attacks<Piece>(s);
+            b = pos.piece_attacks_from<Piece>(s);
         else if (Piece == BISHOP)
             b = bishop_attacks_bb(s, pos.occupied_squares() & ~pos.pieces(QUEEN, us));
         else if (Piece == ROOK)
@@ -773,7 +773,7 @@ namespace {
           if (QueenContactMates && !p.is_check())
           {
             Bitboard escapeSquares =
-                p.piece_attacks<KING>(s) & ~p.pieces_of_color(us) & ~attackedByOthers;
+                p.piece_attacks_from<KING>(s) & ~p.pieces_of_color(us) & ~attackedByOthers;
 
             while (b)
             {
@@ -785,7 +785,7 @@ namespace {
                     for (int i = 0; i < p.piece_count(them, QUEEN); i++)
                     {
                         from = p.piece_list(them, QUEEN, i);
-                        if (    bit_is_set(p.piece_attacks<QUEEN>(from), to)
+                        if (    bit_is_set(p.piece_attacks_from<QUEEN>(from), to)
                             && !bit_is_set(p.pinned_pieces(them), from)
                             && !(rook_attacks_bb(to, occ & ClearMaskBB[from]) & p.pieces(ROOK, QUEEN, us))
                             && !(bishop_attacks_bb(to, occ & ClearMaskBB[from]) & p.pieces(BISHOP, QUEEN, us)))
@@ -801,7 +801,7 @@ namespace {
       // Analyse safe distance checks
       if (QueenCheckBonus > 0 || RookCheckBonus > 0)
       {
-          b = p.piece_attacks<ROOK>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
+          b = p.piece_attacks_from<ROOK>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
 
           // Queen checks
           b2 = b & ei.attacked_by(them, QUEEN);
@@ -815,7 +815,7 @@ namespace {
       }
       if (QueenCheckBonus > 0 || BishopCheckBonus > 0)
       {
-          b = p.piece_attacks<BISHOP>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
+          b = p.piece_attacks_from<BISHOP>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
 
           // Queen checks
           b2 = b & ei.attacked_by(them, QUEEN);
@@ -829,7 +829,7 @@ namespace {
       }
       if (KnightCheckBonus > 0)
       {
-          b = p.piece_attacks<KNIGHT>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
+          b = p.piece_attacks_from<KNIGHT>(s) & ~p.pieces_of_color(them) & ~ei.attacked_by(us);
 
           // Knight checks
           b2 = b & ei.attacked_by(them, KNIGHT);
@@ -954,7 +954,7 @@ namespace {
             b2 = pos.pieces(PAWN, us) & neighboring_files_bb(s);
             if (b2 & rank_bb(s))
                 ebonus += Value(r * 20);
-            else if (pos.pawn_attacks(s, them) & b2)
+            else if (pos.pawn_attacks_from(s, them) & b2)
                 ebonus += Value(r * 12);
 
             // If the other side has only a king, check whether the pawn is

diff --git a/src/movegen.cpp b/src/movegen.cpp
index 7bddeb6e8aa27a2d16b70b2596737961ed884894..2d96ec4c605339f23afb971ed3dfec483c651f1a 100644 (file)
--- a/src/movegen.cpp
+++ b/src/movegen.cpp
@@ -253,7 +253,7 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin
   }
 
   // Generate evasions for king
-  Bitboard b1 = pos.piece_attacks<KING>(ksq) & ~pos.pieces_of_color(us) & ~checkersAttacks;
+  Bitboard b1 = pos.piece_attacks_from<KING>(ksq) & ~pos.pieces_of_color(us) & ~checkersAttacks;
   while (b1)
   {
       to = pop_1st_bit(&b1);
@@ -275,7 +275,7 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin
       // Generate captures of the checking piece
 
       // Pawn captures
-      b1 = pos.pawn_attacks(checksq, them) & pos.pieces(PAWN, us) & ~pinned;
+      b1 = pos.pawn_attacks_from(checksq, them) & pos.pieces(PAWN, us) & ~pinned;
       while (b1)
       {
           from = pop_1st_bit(&b1);
@@ -290,9 +290,9 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin
       }
 
       // Pieces captures
-      b1 = (  (pos.piece_attacks<KNIGHT>(checksq) & pos.pieces(KNIGHT, us))
-            | (pos.piece_attacks<BISHOP>(checksq) & pos.pieces(BISHOP, QUEEN, us))
-            | (pos.piece_attacks<ROOK>(checksq)   & pos.pieces(ROOK, QUEEN, us)) ) & ~pinned;
+      b1 = (  (pos.piece_attacks_from<KNIGHT>(checksq) & pos.pieces(KNIGHT, us))
+            | (pos.piece_attacks_from<BISHOP>(checksq) & pos.pieces(BISHOP, QUEEN, us))
+            | (pos.piece_attacks_from<ROOK>(checksq)   & pos.pieces(ROOK, QUEEN, us)) ) & ~pinned;
 
       while (b1)
       {
@@ -326,7 +326,7 @@ MoveStack* generate_evasions(const Position& pos, MoveStack* mlist, Bitboard pin
       if (pos.ep_square() != SQ_NONE && (checkers & pos.pieces(PAWN, them)))
       {
           to = pos.ep_square();
-          b1 = pos.pawn_attacks(to, them) & pos.pieces(PAWN, us);
+          b1 = pos.pawn_attacks_from(to, them) & pos.pieces(PAWN, us);
 
           // The checking pawn cannot be a discovered (bishop) check candidate
           // otherwise we were in check also before last double push move.
@@ -557,7 +557,7 @@ bool move_is_legal(const Position& pos, const Move m, Bitboard pinned) {
   }
 
   // Luckly we can handle all the other pieces in one go
-  return (   bit_is_set(pos.piece_attacks(pc, from), to)
+  return (   bit_is_set(pos.piece_attacks_from(pc, from), to)
           && pos.pl_move_is_legal(m, pinned)
           && !move_is_promotion(m));
 }
@@ -598,7 +598,7 @@ namespace {
     for (int i = 0, e = pos.piece_count(us, Piece); i < e; i++)
     {
         from = pos.piece_list(us, Piece, i);
-        b = pos.piece_attacks<Piece>(from) & target;
+        b = pos.piece_attacks_from<Piece>(from) & target;
         SERIALIZE_MOVES(b);
     }
     return mlist;
@@ -616,7 +616,7 @@ namespace {
         if (pinned && bit_is_set(pinned, from))
             continue;
 
-        b = pos.piece_attacks<Piece>(from) & target;
+        b = pos.piece_attacks_from<Piece>(from) & target;
         SERIALIZE_MOVES(b);
     }
     return mlist;
@@ -628,7 +628,7 @@ namespace {
     Bitboard b;
     Square from = pos.king_square(us);
 
-    b = pos.piece_attacks<KING>(from) & target;
+    b = pos.piece_attacks_from<KING>(from) & target;
     SERIALIZE_MOVES(b);
     return mlist;
   }
@@ -700,7 +700,7 @@ namespace {
         assert(Us != WHITE || square_rank(pos.ep_square()) == RANK_6);
         assert(Us != BLACK || square_rank(pos.ep_square()) == RANK_3);
 
-        Bitboard b1 = pawns & pos.pawn_attacks(pos.ep_square(), Them);
+        Bitboard b1 = pawns & pos.pawn_attacks_from(pos.ep_square(), Them);
         assert(b1 != EmptyBoardBB);
 
         while (b1)
@@ -819,11 +819,11 @@ namespace {
     // Direct checks, single pawn pushes
     Bitboard empty = pos.empty_squares();
     b2 = move_pawns<Us, DELTA_N>(b1) & empty;
-    b3 = b2 & pos.pawn_attacks(ksq, Them);
+    b3 = b2 & pos.pawn_attacks_from(ksq, Them);
     SERIALIZE_MOVES_D(b3, -TDELTA_N);
 
     // Direct checks, double pawn pushes
-    b3 =  move_pawns<Us, DELTA_N>(b2 & TRank3BB) & empty & pos.pawn_attacks(ksq, Them);
+    b3 =  move_pawns<Us, DELTA_N>(b2 & TRank3BB) & empty & pos.pawn_attacks_from(ksq, Them);
     SERIALIZE_MOVES_D(b3, -TDELTA_N -TDELTA_N);
     return mlist;
   }
@@ -839,7 +839,7 @@ namespace {
     while (b)
     {
         Square from = pop_1st_bit(&b);
-        Bitboard bb = pos.piece_attacks<Piece>(from) & pos.empty_squares();
+        Bitboard bb = pos.piece_attacks_from<Piece>(from) & pos.empty_squares();
         if (Piece == KING)
             bb &= ~QueenPseudoAttacks[ksq];
 
@@ -850,7 +850,7 @@ namespace {
     b = target & ~dc;
     if (Piece != KING || b)
     {
-        Bitboard checkSqs = pos.piece_attacks<Piece>(ksq) & pos.empty_squares();
+        Bitboard checkSqs = pos.piece_attacks_from<Piece>(ksq) & pos.empty_squares();
         if (!checkSqs)
             return mlist;
 
@@ -862,7 +862,7 @@ namespace {
                 || (Piece == BISHOP && !(BishopPseudoAttacks[from] & checkSqs)))
                 continue;
 
-            Bitboard bb = pos.piece_attacks<Piece>(from) & checkSqs;
+            Bitboard bb = pos.piece_attacks_from<Piece>(from) & checkSqs;
             SERIALIZE_MOVES(bb);
         }
     }

diff --git a/src/pawns.cpp b/src/pawns.cpp
index a681571dd9c72c90d76bb23365f7b914ecc7af71..c32fbdec7dfa7d639f85d129df851d52fe569535 100644 (file)
--- a/src/pawns.cpp
+++ b/src/pawns.cpp
@@ -303,7 +303,7 @@ PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) {
         if (   passed
             || isolated
             || chain
-            || (pos.pawn_attacks(s, us) & theirPawns)
+            || (pos.pawn_attacks_from(s, us) & theirPawns)
             || (ourPawns & behind_bb(us, r) & neighboring_files_bb(f)))
             backward = false;
         else
@@ -312,7 +312,7 @@ PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) {
             // pawn on neighboring files. We now check whether the pawn is
             // backward by looking in the forward direction on the neighboring
             // files, and seeing whether we meet a friendly or an enemy pawn first.
-            Bitboard b = pos.pawn_attacks(s, us);
+            Bitboard b = pos.pawn_attacks_from(s, us);
             if (us == WHITE)
             {
                 for ( ; !(b & (ourPawns | theirPawns)); b <<= 8);

diff --git a/src/position.cpp b/src/position.cpp
index c4798fb504c5890f98174cb184d568bb8a3b15ca..ecd0b82918ac50d1582efb9bbc57f87f3bd95df7 100644 (file)
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -384,30 +384,30 @@ Bitboard Position::discovered_check_candidates(Color c) const {
 
 Bitboard Position::attackers_to(Square s) const {
 
-  return  (pawn_attacks(s, BLACK)   & pieces(PAWN, WHITE))
-        | (pawn_attacks(s, WHITE)   & pieces(PAWN, BLACK))
-        | (piece_attacks<KNIGHT>(s) & pieces(KNIGHT))
-        | (piece_attacks<ROOK>(s)   & pieces(ROOK, QUEEN))
-        | (piece_attacks<BISHOP>(s) & pieces(BISHOP, QUEEN))
-        | (piece_attacks<KING>(s)   & pieces(KING));
+  return  (pawn_attacks_from(s, BLACK)   & pieces(PAWN, WHITE))
+        | (pawn_attacks_from(s, WHITE)   & pieces(PAWN, BLACK))
+        | (piece_attacks_from<KNIGHT>(s) & pieces(KNIGHT))
+        | (piece_attacks_from<ROOK>(s)   & pieces(ROOK, QUEEN))
+        | (piece_attacks_from<BISHOP>(s) & pieces(BISHOP, QUEEN))
+        | (piece_attacks_from<KING>(s)   & pieces(KING));
 }
 
-/// Position::piece_attacks() computes a bitboard of all attacks
+/// Position::piece_attacks_from() computes a bitboard of all attacks
 /// of a given piece put in a given square.
 
-Bitboard Position::piece_attacks(Piece p, Square s) const {
+Bitboard Position::piece_attacks_from(Piece p, Square s) const {
 
   assert(square_is_ok(s));
 
   switch (p)
   {
-  case WP:          return pawn_attacks(s, WHITE);
-  case BP:          return pawn_attacks(s, BLACK);
-  case WN: case BN: return piece_attacks<KNIGHT>(s);
-  case WB: case BB: return piece_attacks<BISHOP>(s);
-  case WR: case BR: return piece_attacks<ROOK>(s);
-  case WQ: case BQ: return piece_attacks<QUEEN>(s);
-  case WK: case BK: return piece_attacks<KING>(s);
+  case WP:          return pawn_attacks_from(s, WHITE);
+  case BP:          return pawn_attacks_from(s, BLACK);
+  case WN: case BN: return piece_attacks_from<KNIGHT>(s);
+  case WB: case BB: return piece_attacks_from<BISHOP>(s);
+  case WR: case BR: return piece_attacks_from<ROOK>(s);
+  case WQ: case BQ: return piece_attacks_from<QUEEN>(s);
+  case WK: case BK: return piece_attacks_from<KING>(s);
   default: break;
   }
   return false;
@@ -426,7 +426,7 @@ bool Position::move_attacks_square(Move m, Square s) const {
 
   assert(square_is_occupied(f));
 
-  if (bit_is_set(piece_attacks(piece_on(f), t), s))
+  if (bit_is_set(piece_attacks_from(piece_on(f), t), s))
       return true;
 
   // Move the piece and scan for X-ray attacks behind it
@@ -439,7 +439,7 @@ bool Position::move_attacks_square(Move m, Square s) const {
 
   // If we have attacks we need to verify that are caused by our move
   // and are not already existent ones.
-  return xray && (xray ^ (xray & piece_attacks<QUEEN>(s)));
+  return xray && (xray ^ (xray & piece_attacks_from<QUEEN>(s)));
 }
 
 
@@ -547,7 +547,7 @@ bool Position::move_is_check(Move m, Bitboard dcCandidates) const {
   {
   case PAWN:
 
-      if (bit_is_set(pawn_attacks(ksq, them), to)) // Normal check?
+      if (bit_is_set(pawn_attacks_from(ksq, them), to)) // Normal check?
           return true;
 
       if (   dcCandidates // Discovered check?
@@ -563,7 +563,7 @@ bool Position::move_is_check(Move m, Bitboard dcCandidates) const {
           switch (move_promotion_piece(m))
           {
           case KNIGHT:
-              return bit_is_set(piece_attacks<KNIGHT>(to), ksq);
+              return bit_is_set(piece_attacks_from<KNIGHT>(to), ksq);
           case BISHOP:
               return bit_is_set(bishop_attacks_bb(to, b), ksq);
           case ROOK:
@@ -593,21 +593,21 @@ bool Position::move_is_check(Move m, Bitboard dcCandidates) const {
   // Test discovered check and normal check according to piece type
   case KNIGHT:
     return   (dcCandidates && bit_is_set(dcCandidates, from))
-          || bit_is_set(piece_attacks<KNIGHT>(ksq), to);
+          || bit_is_set(piece_attacks_from<KNIGHT>(ksq), to);
 
   case BISHOP:
     return   (dcCandidates && bit_is_set(dcCandidates, from))
-          || (direction_is_diagonal(ksq, to) && bit_is_set(piece_attacks<BISHOP>(ksq), to));
+          || (direction_is_diagonal(ksq, to) && bit_is_set(piece_attacks_from<BISHOP>(ksq), to));
 
   case ROOK:
     return   (dcCandidates && bit_is_set(dcCandidates, from))
-          || (direction_is_straight(ksq, to) && bit_is_set(piece_attacks<ROOK>(ksq), to));
+          || (direction_is_straight(ksq, to) && bit_is_set(piece_attacks_from<ROOK>(ksq), to));
 
   case QUEEN:
       // Discovered checks are impossible!
       assert(!bit_is_set(dcCandidates, from));
-      return (   (direction_is_straight(ksq, to) && bit_is_set(piece_attacks<ROOK>(ksq), to))
-              || (direction_is_diagonal(ksq, to) && bit_is_set(piece_attacks<BISHOP>(ksq), to)));
+      return (   (direction_is_straight(ksq, to) && bit_is_set(piece_attacks_from<ROOK>(ksq), to))
+              || (direction_is_diagonal(ksq, to) && bit_is_set(piece_attacks_from<BISHOP>(ksq), to)));
 
   case KING:
       // Discovered check?
@@ -661,22 +661,23 @@ inline void Position::update_checkers(Bitboard* pCheckersBB, Square ksq, Square
   // Direct checks
   if (  (   (Bishop && bit_is_set(BishopPseudoAttacks[ksq], to))
          || (Rook   && bit_is_set(RookPseudoAttacks[ksq], to)))
-      && bit_is_set(piece_attacks<Piece>(ksq), to)) // slow, try to early skip
+      && bit_is_set(piece_attacks_from<Piece>(ksq), to)) // slow, try to early skip
       set_bit(pCheckersBB, to);
 
   else if (   Piece != KING
            && !Slider
-           && bit_is_set(Piece == PAWN ? pawn_attacks(ksq, opposite_color(sideToMove)) : piece_attacks<Piece>(ksq), to))
+           && bit_is_set(Piece == PAWN ? pawn_attacks_from(ksq, opposite_color(sideToMove))
+                                       : piece_attacks_from<Piece>(ksq), to))
       set_bit(pCheckersBB, to);
 
   // Discovery checks
   if (Piece != QUEEN && bit_is_set(dcCandidates, from))
   {
       if (Piece != ROOK)
-          (*pCheckersBB) |= (piece_attacks<ROOK>(ksq) & pieces(ROOK, QUEEN, side_to_move()));
+          (*pCheckersBB) |= (piece_attacks_from<ROOK>(ksq) & pieces(ROOK, QUEEN, side_to_move()));
 
       if (Piece != BISHOP)
-          (*pCheckersBB) |= (piece_attacks<BISHOP>(ksq) & pieces(BISHOP, QUEEN, side_to_move()));
+          (*pCheckersBB) |= (piece_attacks_from<BISHOP>(ksq) & pieces(BISHOP, QUEEN, side_to_move()));
   }
 }
 
@@ -805,7 +806,7 @@ void Position::do_move(Move m, StateInfo& newSt, Bitboard dcCandidates) {
       // Set en passant square, only if moved pawn can be captured
       if (abs(int(to) - int(from)) == 16)
       {
-          if (pawn_attacks(from + (us == WHITE ? DELTA_N : DELTA_S), us) & pieces(PAWN, them))
+          if (pawn_attacks_from(from + (us == WHITE ? DELTA_N : DELTA_S), us) & pieces(PAWN, them))
           {
               st->epSquare = Square((int(from) + int(to)) / 2);
               key ^= zobEp[st->epSquare];
@@ -1359,10 +1360,10 @@ int Position::see(Square from, Square to) const {
       clear_bit(&occ, from);
       attackers =  (rook_attacks_bb(to, occ)   & pieces(ROOK, QUEEN))
                  | (bishop_attacks_bb(to, occ) & pieces(BISHOP, QUEEN))
-                 | (piece_attacks<KNIGHT>(to)  & pieces(KNIGHT))
-                 | (piece_attacks<KING>(to)    & pieces(KING))
-                 | (pawn_attacks(to, WHITE)    & pieces(PAWN, BLACK))
-                 | (pawn_attacks(to, BLACK)    & pieces(PAWN, WHITE));
+                 | (piece_attacks_from<KNIGHT>(to)  & pieces(KNIGHT))
+                 | (piece_attacks_from<KING>(to)    & pieces(KING))
+                 | (pawn_attacks_from(to, WHITE)    & pieces(PAWN, BLACK))
+                 | (pawn_attacks_from(to, BLACK)    & pieces(PAWN, WHITE));
 
       if (from != SQ_NONE)
           break;

diff --git a/src/position.h b/src/position.h
index d47d84b7633c40924e38439e4b41a4fb0dd54ba6..9b5129a9c172fffc4000279abb0f8f7917a3285f 100644 (file)
--- a/src/position.h
+++ b/src/position.h
@@ -195,12 +195,12 @@ public:
   // Piece lists
   Square piece_list(Color c, PieceType pt, int index) const;
 
-  // Attack information to a given square
+  // Information about attacks to or from a given square
   Bitboard attackers_to(Square s) const;
   Bitboard attackers_to(Square s, Color c) const;
-  Bitboard piece_attacks(Piece p, Square s) const;
-  Bitboard pawn_attacks(Square s, Color c) const;
-  template<PieceType> Bitboard piece_attacks(Square s) const;
+  Bitboard piece_attacks_from(Piece p, Square s) const;
+  Bitboard pawn_attacks_from(Square s, Color c) const;
+  template<PieceType> Bitboard piece_attacks_from(Square s) const;
 
   // Properties of moves
   bool pl_move_is_legal(Move m) const;
@@ -433,33 +433,33 @@ inline Square Position::initial_qr_square(Color c) const {
   return relative_square(c, make_square(initialQRFile, RANK_1));
 }
 
-inline Bitboard Position::pawn_attacks(Square s, Color c) const {
+inline Bitboard Position::pawn_attacks_from(Square s, Color c) const {
   return StepAttackBB[piece_of_color_and_type(c, PAWN)][s];
 }
 
 template<PieceType Piece> // Knight and King
-inline Bitboard Position::piece_attacks(Square s) const {
+inline Bitboard Position::piece_attacks_from(Square s) const {
   return StepAttackBB[Piece][s];
 }
 
 template<>
-inline Bitboard Position::piece_attacks<PAWN>(Square s) const {
+inline Bitboard Position::piece_attacks_from<PAWN>(Square s) const {
   return StepAttackBB[WP][s] | StepAttackBB[BP][s];
 }
 
 template<>
-inline Bitboard Position::piece_attacks<BISHOP>(Square s) const {
+inline Bitboard Position::piece_attacks_from<BISHOP>(Square s) const {
   return bishop_attacks_bb(s, occupied_squares());
 }
 
 template<>
-inline Bitboard Position::piece_attacks<ROOK>(Square s) const {
+inline Bitboard Position::piece_attacks_from<ROOK>(Square s) const {
   return rook_attacks_bb(s, occupied_squares());
 }
 
 template<>
-inline Bitboard Position::piece_attacks<QUEEN>(Square s) const {
-  return piece_attacks<ROOK>(s) | piece_attacks<BISHOP>(s);
+inline Bitboard Position::piece_attacks_from<QUEEN>(Square s) const {
+  return piece_attacks_from<ROOK>(s) | piece_attacks_from<BISHOP>(s);
 }
 
 inline Bitboard Position::checkers() const {

diff --git a/src/search.cpp b/src/search.cpp
index acd5d1da4ef7793f7ba02668b5907c2a461ff75e..55b2e92c883fcae9cf6b0362c102a174f5dd3127 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -2182,7 +2182,7 @@ namespace {
 
     // Case 4: The destination square for m2 is attacked by the moving piece in m1
     p = pos.piece_on(t1);
-    if (bit_is_set(pos.piece_attacks(p, t1), t2))
+    if (bit_is_set(pos.piece_attacks_from(p, t1), t2))
         return true;
 
     // Case 5: Discovered check, checking piece is the piece moved in m1