simplified and increased threshold to switch between NNUE and classical

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index d20c7b70f1e12407a4b58a6524469422b252f040..1ae6cb3ac56f88d91ca8d56be259505d2a5f35e5 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -110,7 +110,7 @@ namespace {
   constexpr Value LazyThreshold1 =  Value(1400);
   constexpr Value LazyThreshold2 =  Value(1300);
   constexpr Value SpaceThreshold = Value(12222);
-  constexpr Value NNUEThreshold  =   Value(500);
+  constexpr Value NNUEThreshold  =   Value(520);
 
   // KingAttackWeights[PieceType] contains king attack weights by piece type
   constexpr int KingAttackWeights[PIECE_TYPE_NB] = { 0, 0, 81, 52, 44, 10 };
@@ -345,7 +345,8 @@ namespace {
         {
             // Bonus if the piece is on an outpost square or can reach one
             // Reduced bonus for knights (BadOutpost) if few relevant targets
-            bb = OutpostRanks & attackedBy[Us][PAWN] & ~pe->pawn_attacks_span(Them);
+            bb = OutpostRanks & (attackedBy[Us][PAWN] | shift<Down>(pos.pieces(PAWN)))
+                              & ~pe->pawn_attacks_span(Them);
             Bitboard targets = pos.pieces(Them) & ~pos.pieces(PAWN);
 
             if (   Pt == KNIGHT
@@ -938,10 +939,9 @@ Value Eval::evaluate(const Position& pos) {
 
   if (Eval::useNNUE)
   {
-      Value balance = pos.non_pawn_material(WHITE) - pos.non_pawn_material(BLACK);
-      balance += 200 * (pos.count<PAWN>(WHITE) - pos.count<PAWN>(BLACK));
+      Value v = eg_value(pos.psq_score());
       // Take NNUE eval only on balanced positions
-      if (abs(balance) < NNUEThreshold)
+      if (abs(v) < NNUEThreshold)
          return NNUE::evaluate(pos) + Tempo;
   }
   return Evaluation<NO_TRACE>(pos).value();