New NNUE architecture and net

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 403d59dd70d0cc0deb1b5f6f69433ff784a9ba44..256bd9944f3a6e9a4bb6a0c3a186117af56dcc93 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -120,7 +120,7 @@ namespace Eval {
 
     if (filename.has_value())
         actualFilename = filename.value();
-    else 
+    else
     {
         if (eval_file_loaded != EvalFileDefaultName)
         {
@@ -1116,10 +1116,8 @@ Value Eval::evaluate(const Position& pos) {
       // Scale and shift NNUE for compatibility with search and classical evaluation
       auto  adjusted_NNUE = [&]()
       {
-         int material = pos.non_pawn_material() + 4 * PawnValueMg * pos.count<PAWN>();
-         int scale =  580
-                    + material / 32
-                    - 4 * pos.rule50_count();
+
+         int scale = 903 + 28 * pos.count<PAWN>() + 28 * pos.non_pawn_material() / 1024;
 
          Value nnue = NNUE::evaluate(pos) * scale / 1024 + Time.tempoNNUE;
 
@@ -1134,7 +1132,7 @@ Value Eval::evaluate(const Position& pos) {
       Value psq = Value(abs(eg_value(pos.psq_score())));
       int   r50 = 16 + pos.rule50_count();
       bool  largePsq = psq * 16 > (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50;
-      bool  classical = largePsq || (psq > PawnValueMg / 4 && !(pos.this_thread()->nodes & 0xB));
+      bool  classical = largePsq;
 
       // Use classical evaluation for really low piece endgames.
       // One critical case is the draw for bishop + A/H file pawn vs naked king.
@@ -1151,8 +1149,7 @@ Value Eval::evaluate(const Position& pos) {
           && !lowPieceEndgame
           && (   abs(v) * 16 < NNUEThreshold2 * r50
               || (   pos.opposite_bishops()
-                  && abs(v) * 16 < (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50
-                  && !(pos.this_thread()->nodes & 0xB))))
+                  && abs(v) * 16 < (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50)))
           v = adjusted_NNUE();
   }