Tuned some pawns and evaluation constants

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index c98a83fc81a777806b111d80200946eaeb271da7..d2aab71df68c393c5e0323d87514efdaf523aa64 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -146,23 +146,23 @@ namespace {
 
   // PassedRank[Rank] contains a bonus according to the rank of a passed pawn
   constexpr Score PassedRank[RANK_NB] = {
-    S(0, 0), S(5, 7), S(5, 13), S(32, 42), S(70, 70), S(172, 170), S(217, 269)
+    S(0, 0), S(5, 7), S(5, 13), S(18, 23), S(74, 58), S(164, 166), S(268, 243)
   };
 
   // PassedFile[File] contains a bonus according to the file of a passed pawn
   constexpr Score PassedFile[FILE_NB] = {
-    S(  9, 10), S(2, 10), S(1, -8), S(-20,-12),
-    S(-20,-12), S(1, -8), S(2, 10), S(  9, 10)
+    S( 15,  7), S(-5, 14), S( 1, -5), S(-22,-11),
+    S(-22,-11), S( 1, -5), S(-5, 14), S( 15,  7)
   };
 
   // PassedDanger[Rank] contains a term to weight the passed score
-  constexpr int PassedDanger[RANK_NB] = { 0, 0, 0, 2, 7, 12, 19 };
+  constexpr int PassedDanger[RANK_NB] = { 0, 0, 0, 3, 6, 12, 21 };
 
   // KingProtector[PieceType-2] contains a penalty according to distance from king
   constexpr Score KingProtector[] = { S(3, 5), S(4, 3), S(3, 0), S(1, -1) };
 
   // Assorted bonuses and penalties
-  constexpr Score BishopPawns        = S(  8, 12);
+  constexpr Score BishopPawns        = S(  3,  5);
   constexpr Score CloseEnemies       = S(  7,  0);
   constexpr Score Connectivity       = S(  3,  1);
   constexpr Score CorneredBishop     = S( 50, 50);
@@ -293,7 +293,8 @@ namespace {
   template<Tracing T> template<Color Us, PieceType Pt>
   Score Evaluation<T>::pieces() {
 
-    constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
+    constexpr Color     Them = (Us == WHITE ? BLACK : WHITE);
+    constexpr Direction Down = (Us == WHITE ? SOUTH : NORTH);
     constexpr Bitboard OutpostRanks = (Us == WHITE ? Rank4BB | Rank5BB | Rank6BB
                                                    : Rank5BB | Rank4BB | Rank3BB);
     const Square* pl = pos.squares<Pt>(Us);
@@ -349,8 +350,12 @@ namespace {
 
             if (Pt == BISHOP)
             {
-                // Penalty according to number of pawns on the same color square as the bishop
-                score -= BishopPawns * pe->pawns_on_same_color_squares(Us, s);
+                // Penalty according to number of pawns on the same color square as the
+                // bishop, bigger when the center files are blocked with pawns.
+                Bitboard blocked = pos.pieces(Us, PAWN) & shift<Down>(pos.pieces());
+
+                score -= BishopPawns * pe->pawns_on_same_color_squares(Us, s)
+                                     * (1 + popcount(blocked & CenterFiles));
 
                 // Bonus for bishop on a long diagonal which can "see" both center squares
                 if (more_than_one(Center & (attacks_bb<BISHOP>(s, pos.pieces(PAWN)) | s)))