Value v;
- // Deciding between classical and NNUE eval: for high PSQ imbalance we use classical,
+ // Deciding between classical and NNUE eval (~10 Elo): for high PSQ imbalance we use classical,
// but we switch to NNUE during long shuffling or with high material on the board.
+ bool classical = false;
+
if ( !useNNUE
|| abs(eg_value(pos.psq_score())) * 5 > (850 + pos.non_pawn_material() / 64) * (5 + pos.rule50_count()))
+ {
v = Evaluation<NO_TRACE>(pos).value(); // classical
- else
+ classical = abs(v) >= 300;
+ }
+
+ // If result of a classical evaluation is much lower than threshold fall back to NNUE
+ if (!classical && useNNUE)
{
- int scale = 1049
- + 8 * pos.count<PAWN>()
+ int scale = 1136
+ 20 * pos.non_pawn_material() / 1024;
Value nnue = NNUE::evaluate(pos, true); // NNUE