Improve play for closed positions

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index c137fab5ad53b3197a793b97a9c860f4d65408ad..6bd3c08b5133a672bab8616c57108a0a6704bd70 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -225,7 +225,7 @@ namespace {
   // BishopPawns[distance from edge] contains a file-dependent penalty for pawns on
   // squares of the same color as our bishop.
   constexpr Score BishopPawns[int(FILE_NB) / 2] = {
-    S(3, 8), S(3, 9), S(1, 8), S(3, 7)
+    S(3, 8), S(3, 9), S(2, 8), S(3, 8)
   };
 
   // KingProtector[knight/bishop] contains penalty for each distance unit to own king
@@ -233,7 +233,7 @@ namespace {
 
   // Outpost[knight/bishop] contains bonuses for each knight or bishop occupying a
   // pawn protected square on rank 4 to 6 which is also safe from a pawn attack.
-  constexpr Score Outpost[] = { S(56, 34), S(31, 23) };
+  constexpr Score Outpost[] = { S(57, 38), S(31, 24) };
 
   // PassedRank[Rank] contains a bonus according to the rank of a passed pawn
   constexpr Score PassedRank[RANK_NB] = {
@@ -255,7 +255,7 @@ namespace {
   };
 
   // Assorted bonuses and penalties
-  constexpr Score BadOutpost          = S( -7, 36);
+  constexpr Score UncontestedOutpost  = S(  1, 10);
   constexpr Score BishopOnKingRing    = S( 24,  0);
   constexpr Score BishopXRayPawns     = S(  4,  5);
   constexpr Score CorneredBishop      = S( 50, 50);
@@ -428,7 +428,7 @@ namespace {
         if (Pt == BISHOP || Pt == KNIGHT)
         {
             // Bonus if the piece is on an outpost square or can reach one
-            // Reduced bonus for knights (BadOutpost) if few relevant targets
+            // Bonus for knights (UncontestedOutpost) if few relevant targets
             bb = OutpostRanks & (attackedBy[Us][PAWN] | shift<Down>(pos.pieces(PAWN)))
                               & ~pe->pawn_attacks_span(Them);
             Bitboard targets = pos.pieces(Them) & ~pos.pieces(PAWN);
@@ -437,7 +437,7 @@ namespace {
                 && bb & s & ~CenterFiles // on a side outpost
                 && !(b & targets)        // no relevant attacks
                 && (!more_than_one(targets & (s & QueenSide ? QueenSide : KingSide))))
-                score += BadOutpost;
+                score += UncontestedOutpost * popcount(pos.pieces(PAWN) & (s & QueenSide ? QueenSide : KingSide));
             else if (bb & s)
                 score += Outpost[Pt == BISHOP];
             else if (Pt == KNIGHT && bb & b & ~pos.pieces(Us))
@@ -1052,8 +1052,8 @@ Value Eval::evaluate(const Position& pos) {
   {
       // Scale and shift NNUE for compatibility with search and classical evaluation
       auto  adjusted_NNUE = [&](){
-         int mat = pos.non_pawn_material() + PawnValueMg * pos.count<PAWN>();
-         return NNUE::evaluate(pos) * (679 + mat / 32) / 1024 + Tempo;
+         int mat = pos.non_pawn_material() + 2 * PawnValueMg * pos.count<PAWN>();
+         return NNUE::evaluate(pos) * (641 + mat / 32 - 4 * pos.rule50_count()) / 1024 + Tempo;
       };
 
       // If there is PSQ imbalance use classical eval, with small probability if it is small