From: ElbertoOne <lubvdberg@gmail.com>
Date: Sat, 1 Dec 2018 09:28:10 +0000 (+0100)
Subject: Remove Overload bonus
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=79e3710fd224e6e052f6bc5420a8f8f03bf41e18;ds=inline

Remove Overload bonus

Compensate by giving the Hanging bonus to weak doubly-attacked
non pawn enemies pieces.

STC: http://tests.stockfishchess.org/tests/view/5bfd53c40ebc5902bced9237
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 62107 W: 13664 L: 13622 D: 34821

LTC: http://tests.stockfishchess.org/tests/view/5bfd74700ebc5902bced9618
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 86406 W: 14381 L: 14365 D: 57660

A possible follow up would be to tune the hanging bonus and/or try to
simplify the hanging bonus condition.

Bench: 3810849
---

diff --git a/AUTHORS b/AUTHORS
index dd2c1e38..5b646dae 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -20,9 +20,9 @@ Balint Pfliegel
 Ben Koshy (BKSpurgeon)
 Bill Henry (VoyagerOne)
 braich
+Bojun Guo (noobpwnftw)
 Brian Sheppard (SapphireBrand)
 Bryan Cross (crossbr)
-Bujun Guo (noobpwnftw)
 Chris Cain (ceebo)
 Dan Schmidt
 Daniel Dugovic (ddugovic)
@@ -31,7 +31,6 @@ David Zar
 Daylen Yang (daylen)
 DiscanX
 Eelco de Groot
-ElbertoOne
 erbsenzaehler
 Ernesto Gatti
 Fabian Beuke (madnight)
@@ -76,6 +75,7 @@ Leonardo Ljubičić (ICCF World Champion)
 Leonid Pechenik (lp--)
 Linus Arver
 loco-loco
+Lub van den Berg (ElbertoOne)
 Luca Brivio (lucabrivio)
 Lucas Braesch (lucasart)
 Lyudmil Antonov (lantonov)
diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index aeaa4336..f1bb861d 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -160,7 +160,6 @@ namespace {
   constexpr Score KnightOnQueen      = S( 20, 12);
   constexpr Score LongDiagonalBishop = S( 44,  0);
   constexpr Score MinorBehindPawn    = S( 16,  0);
-  constexpr Score Overload           = S( 12,  6);
   constexpr Score PawnlessFlank      = S( 18, 94);
   constexpr Score RestrictedPiece    = S(  7,  6);
   constexpr Score RookOnPawn         = S( 10, 28);
@@ -553,10 +552,9 @@ namespace {
         if (weak & attackedBy[Us][KING])
             score += ThreatByKing;
 
-        score += Hanging * popcount(weak & ~attackedBy[Them][ALL_PIECES]);
-
-        b = weak & nonPawnEnemies & attackedBy[Them][ALL_PIECES];
-        score += Overload * popcount(b);
+        b =  ~attackedBy[Them][ALL_PIECES]
+           | (nonPawnEnemies & attackedBy2[Us]);
+        score += Hanging * popcount(weak & b);
     }
 
     // Bonus for restricting their piece moves