From 0186904f53e6b9c90935cd8fe822da795ca9d333 Mon Sep 17 00:00:00 2001
From: Linmiao Xu <linmiao.xu@gmail.com>
Date: Sun, 29 Sep 2024 04:22:37 -0400
Subject: [PATCH] Remove evaluation grain

Passed non-regression STC:
https://tests.stockfishchess.org/tests/view/66fa345a86d5ee47d953b86e
LLR: 2.96 (-2.94,2.94) <-1.75,0.25>
Total: 39776 W: 10528 L: 10306 D: 18942
Ptnml(0-2): 134, 4674, 10063, 4870, 147

Passed non-regression LTC:
https://tests.stockfishchess.org/tests/view/66facfb886d5ee47d953b8a8
LLR: 2.94 (-2.94,2.94) <-1.75,0.25>
Total: 64230 W: 16484 L: 16305 D: 31441
Ptnml(0-2): 38, 7195, 17483, 7348, 51

closes https://github.com/official-stockfish/Stockfish/pull/5613

bench 1013135
---
 src/evaluate.cpp | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 087765e3..b1c7283e 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -83,9 +83,6 @@ Value Eval::evaluate(const Eval::NNUE::Networks&    networks,
     int material = (smallNet ? 553 : 532) * pos.count<PAWN>() + pos.non_pawn_material();
     v = (nnue * (76898 + material) + optimism * (8112 + material)) / (smallNet ? 74411 : 76256);
 
-    // Evaluation grain (to get more alpha-beta cuts) with randomization (for robustness)
-    v = (v / 16) * 16 - 1 + (pos.key() & 0x2);
-
     // Damp down the evaluation linearly when shuffling
     v -= v * pos.rule50_count() / 212;