From: Fabian Fichter <ianfab@users.noreply.github.com>
Date: Wed, 23 Dec 2020 22:41:52 +0000 (+0100)
Subject: Enable pure NNUE for most variants
X-Git-Url: http://winboard.nl/cgi-bin?a=commitdiff_plain;h=9fe03e393c490e316a4adfc44ee0e175c717243e;p=fairystockfish.git

Enable pure NNUE for most variants

Since NNUE is faster and better than classical evaluation,
use pure NNUE for all variants except 3check.

makpong STC
ELO: 94.32 +-43.1 (95%) LOS: 100.0%
Total: 200 W: 102 L: 49 D: 49

makpong LTC
ELO: 96.19 +-59.2 (95%) LOS: 100.0%
Total: 100 W: 49 L: 22 D: 29

minixiangqi STC
ELO: 75.88 +-34.3 (95%) LOS: 100.0%
Total: 200 W: 72 L: 29 D: 99

minixiangqi LTC
ELO: 70.44 +-49.4 (95%) LOS: 99.8%
Total: 100 W: 36 L: 16 D: 48

racingkings STC
ELO: 57.86 +-25.8 (95%) LOS: 100.0%
Total: 400 W: 147 L: 81 D: 172

racingkings LTC
ELO: 56.07 +-50.4 (95%) LOS: 98.7%
Total: 100 W: 35 L: 19 D: 46

losers STC
ELO: 63.23 +-65.5 (95%) LOS: 97.5%
Total: 100 W: 53 L: 35 D: 12

losers LTC
ELO: 31.35 +-65.9 (95%) LOS: 82.8%
Total: 100 W: 50 L: 41 D: 9
---

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 98b2145..6880f69 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -1507,7 +1507,7 @@ Value Eval::evaluate(const Position& pos) {
       // If there is PSQ imbalance use classical eval, with small probability if it is small
       Value psq = Value(abs(eg_value(pos.psq_score())));
       int   r50 = 16 + pos.rule50_count();
-      bool  pure = pos.capture_the_flag_piece() && pos.checking_permitted();
+      bool  pure = !pos.check_counting();
       bool  largePsq = psq * 16 > (NNUEThreshold1 + pos.non_pawn_material() / 64) * r50 && !pure;
       bool  classical = largePsq || (psq > PawnValueMg / 4 && !(pos.this_thread()->nodes & 0xB) && !pure);