/// evaluate() is the evaluator for the outer world. It returns a static
/// evaluation of the position from the point of view of the side to move.
-Value Eval::evaluate(const Position& pos, int* complexity) {
+Value Eval::evaluate(const Position& pos) {
assert(!pos.checkers());
else
{
int nnueComplexity;
- int scale = 1001 + pos.non_pawn_material() / 64;
+ int npm = pos.non_pawn_material() / 64;
Color stm = pos.side_to_move();
Value optimism = pos.this_thread()->optimism[stm];
Value nnue = NNUE::evaluate(pos, true, &nnueComplexity);
// Blend nnue complexity with (semi)classical complexity
- nnueComplexity = ( 406 * nnueComplexity
- + (424 + optimism) * abs(psq - nnue)
- ) / 1024;
+ nnueComplexity = 25 * (nnueComplexity + abs(psq - nnue)) / 64;
- // Return hybrid NNUE complexity to caller
- if (complexity)
- *complexity = nnueComplexity;
-
- optimism = optimism * (272 + nnueComplexity) / 256;
- v = (nnue * scale + optimism * (scale - 748)) / 1024;
+ optimism += optimism * nnueComplexity / 256;
+ v = (nnue * (945 + npm) + optimism * (174 + npm)) / 1024;
}
// Damp down the evaluation linearly when shuffling
// Guarantee evaluation does not hit the tablebase range
v = std::clamp(v, VALUE_TB_LOSS_IN_MAX_PLY + 1, VALUE_TB_WIN_IN_MAX_PLY - 1);
- // When not using NNUE, return classical complexity to caller
- if (complexity && useClassical)
- *complexity = abs(v - psq);
-
return v;
}