From 540b49a1522440597501aa94618cf391cef08feb Mon Sep 17 00:00:00 2001
From: Alain SAVARD <support@multicim.com>
Date: Tue, 6 Oct 2015 03:32:26 +0100
Subject: [PATCH 1/1] Remove queen threat evaluation

Threats by queen seem to be worthless.

STC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 13627 W: 2607 L: 2473 D: 8547

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 19146 W: 2950 L: 2827 D: 13369

Bench: 8222484

Resolves #439
---
 src/evaluate.cpp | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index f66ba58c..c83ec546 100644
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -148,13 +148,13 @@ namespace {
     { S(18, 5), S(27, 8) }  // Bishops
   };
 
-  // Threat[defended/weak][minor/major attacking][attacked PieceType] contains
+  // Threat[defended/weak][minor/rook attacking][attacked PieceType] contains
   // bonuses according to which piece type attacks which one.
   const Score Threat[][2][PIECE_TYPE_NB] = {
-  { { S(0, 0), S( 0, 0), S(19, 37), S(24, 37), S(44, 97), S(35,106) },   // Defended Minor
-    { S(0, 0), S( 0, 0), S( 9, 14), S( 9, 14), S( 7, 14), S(24, 48) } }, // Defended Major
-  { { S(0, 0), S( 0,32), S(33, 41), S(31, 50), S(41,100), S(35,104) },   // Weak Minor
-    { S(0, 0), S( 0,27), S(26, 57), S(26, 57), S(0 , 43), S(23, 51) } }  // Weak Major
+  { { S(0, 0), S( 0, 0), S(19, 37), S(24, 37), S(44, 97), S(35,106) },   // Minor on Defended
+    { S(0, 0), S( 0, 0), S( 9, 14), S( 9, 14), S( 7, 14), S(24, 48) } }, // Rook on Defended
+  { { S(0, 0), S( 0,32), S(33, 41), S(31, 50), S(41,100), S(35,104) },   // Minor on Weak
+    { S(0, 0), S( 0,27), S(26, 57), S(26, 57), S(0 , 43), S(23, 51) } }  // Rook on Weak
   };
 
   // ThreatenedByPawn[PieceType] contains a penalty according to which piece
@@ -502,7 +502,7 @@ namespace {
     const Bitboard TRank7BB = (Us == WHITE ? Rank7BB  : Rank2BB);
 
     enum { Defended, Weak };
-    enum { Minor, Major };
+    enum { Minor, Rook };
 
     Bitboard b, weak, defended, safeThreats;
     Score score = SCORE_ZERO;
@@ -534,9 +534,9 @@ namespace {
         while (b)
             score += Threat[Defended][Minor][type_of(pos.piece_on(pop_lsb(&b)))];
 
-        b = defended & (ei.attackedBy[Us][ROOK]);
+        b = defended & ei.attackedBy[Us][ROOK];
         while (b)
-            score += Threat[Defended][Major][type_of(pos.piece_on(pop_lsb(&b)))];
+            score += Threat[Defended][Rook][type_of(pos.piece_on(pop_lsb(&b)))];
     }
 
     // Enemies not defended by a pawn and under our attack
@@ -551,9 +551,9 @@ namespace {
         while (b)
             score += Threat[Weak][Minor][type_of(pos.piece_on(pop_lsb(&b)))];
 
-        b = weak & (ei.attackedBy[Us][ROOK] | ei.attackedBy[Us][QUEEN]);
+        b = weak & ei.attackedBy[Us][ROOK];
         while (b)
-            score += Threat[Weak][Major][type_of(pos.piece_on(pop_lsb(&b)))];
+            score += Threat[Weak][Rook][type_of(pos.piece_on(pop_lsb(&b)))];
 
         b = weak & ~ei.attackedBy[Them][ALL_PIECES];
         if (b)
-- 
2.39.2