Display classic and NNUE evaluation in trace mode

show both the classical and NNUE evaluation,
as well as the Final evaluation.

closes #3042

No functional change.

src/evaluate.cpp

@@ -972,42 +972,47 @@ std::string Eval::trace(const Position& pos) {
 
   Value v;
 
+  std::memset(scores, 0, sizeof(scores));
+
+  pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt
+
+  v = Evaluation<TRACE>(pos).value();
+
+  ss << std::showpoint << std::noshowpos << std::fixed << std::setprecision(2)
+     << "     Term    |    White    |    Black    |    Total   \n"
+     << "             |   MG    EG  |   MG    EG  |   MG    EG \n"
+     << " ------------+-------------+-------------+------------\n"
+     << "    Material | " << Term(MATERIAL)
+     << "   Imbalance | " << Term(IMBALANCE)
+     << "       Pawns | " << Term(PAWN)
+     << "     Knights | " << Term(KNIGHT)
+     << "     Bishops | " << Term(BISHOP)
+     << "       Rooks | " << Term(ROOK)
+     << "      Queens | " << Term(QUEEN)
+     << "    Mobility | " << Term(MOBILITY)
+     << " King safety | " << Term(KING)
+     << "     Threats | " << Term(THREAT)
+     << "      Passed | " << Term(PASSED)
+     << "       Space | " << Term(SPACE)
+     << "    Winnable | " << Term(WINNABLE)
+     << " ------------+-------------+-------------+------------\n"
+     << "       Total | " << Term(TOTAL);
+
+  v = pos.side_to_move() == WHITE ? v : -v;
+
+  ss << "\nClassical evaluation: " << to_cp(v) << " (white side)\n";
+
   if (Eval::useNNUE)
   {
       v = NNUE::evaluate(pos);
-  }
-  else
-  {
-      std::memset(scores, 0, sizeof(scores));
-
-      pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt
-
-      v = Evaluation<TRACE>(pos).value();
-
-      ss << std::showpoint << std::noshowpos << std::fixed << std::setprecision(2)
-         << "     Term    |    White    |    Black    |    Total   \n"
-         << "             |   MG    EG  |   MG    EG  |   MG    EG \n"
-         << " ------------+-------------+-------------+------------\n"
-         << "    Material | " << Term(MATERIAL)
-         << "   Imbalance | " << Term(IMBALANCE)
-         << "       Pawns | " << Term(PAWN)
-         << "     Knights | " << Term(KNIGHT)
-         << "     Bishops | " << Term(BISHOP)
-         << "       Rooks | " << Term(ROOK)
-         << "      Queens | " << Term(QUEEN)
-         << "    Mobility | " << Term(MOBILITY)
-         << " King safety | " << Term(KING)
-         << "     Threats | " << Term(THREAT)
-         << "      Passed | " << Term(PASSED)
-         << "       Space | " << Term(SPACE)
-         << "    Winnable | " << Term(WINNABLE)
-         << " ------------+-------------+-------------+------------\n"
-         << "       Total | " << Term(TOTAL);
+      v = pos.side_to_move() == WHITE ? v : -v;
+      ss << "\nNNUE evaluation:      " << to_cp(v) << " (white side)\n";
   }
 
+  v = evaluate(pos);
   v = pos.side_to_move() == WHITE ? v : -v;
+  ss << "\nFinal evaluation:     " << to_cp(v) << " (white side)\n";
 
-  ss << "\nFinal evaluation: " << to_cp(v) << " (white side)\n";
 
   return ss.str();
 }