Update Elo estimates for terms in search

[stockfish] / src / evaluate.cpp

diff --git a/src/evaluate.cpp b/src/evaluate.cpp
index 116d5d6616838696d1b6787a85d8fc2f029e7c40..7c7ce95cebcf27d72960c0d34d45857e3d10f052 100644 (file)
--- a/src/evaluate.cpp
+++ b/src/evaluate.cpp
@@ -2,7 +2,7 @@
   Stockfish, a UCI chess playing engine derived from Glaurung 2.1
   Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
   Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
-  Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
+  Copyright (C) 2015-2020 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
 
   Stockfish is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
@@ -145,7 +145,7 @@ namespace {
   constexpr Score ThreatByKing       = S( 24, 89);
   constexpr Score ThreatByPawnPush   = S( 48, 39);
   constexpr Score ThreatBySafePawn   = S(173, 94);
-  constexpr Score TrappedRook        = S( 47,  4);
+  constexpr Score TrappedRook        = S( 52, 10);
   constexpr Score WeakQueen          = S( 49, 15);
 
 #undef S
@@ -225,9 +225,9 @@ namespace {
     // Find our pawns that are blocked or on the first two ranks
     Bitboard b = pos.pieces(Us, PAWN) & (shift<Down>(pos.pieces()) | LowRanks);
 
-    // Squares occupied by those pawns, by our king or queen or controlled by
-    // enemy pawns are excluded from the mobility area.
-    mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pe->pawn_attacks(Them));
+    // Squares occupied by those pawns, by our king or queen, by blockers to attacks on our king
+    // or controlled by enemy pawns are excluded from the mobility area.
+    mobilityArea[Us] = ~(b | pos.pieces(Us, KING, QUEEN) | pos.blockers_for_king(Us) | pe->pawn_attacks(Them));
 
     // Initialize attackedBy[] for king and pawns
     attackedBy[Us][KING] = pos.attacks_from<KING>(ksq);
@@ -317,20 +317,19 @@ namespace {
                 // Bonus for bishop on a long diagonal which can "see" both center squares
                 if (more_than_one(attacks_bb<BISHOP>(s, pos.pieces(PAWN)) & Center))
                     score += LongDiagonalBishop;
-            }
 
-            // An important Chess960 pattern: A cornered bishop blocked by a friendly
-            // pawn diagonally in front of it is a very serious problem, especially
-            // when that pawn is also blocked.
-            if (   Pt == BISHOP
-                && pos.is_chess960()
-                && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1)))
-            {
-                Direction d = pawn_push(Us) + (file_of(s) == FILE_A ? EAST : WEST);
-                if (pos.piece_on(s + d) == make_piece(Us, PAWN))
-                    score -= !pos.empty(s + d + pawn_push(Us))                ? CorneredBishop * 4
-                            : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? CorneredBishop * 2
-                                                                              : CorneredBishop;
+                // An important Chess960 pattern: a cornered bishop blocked by a friendly
+                // pawn diagonally in front of it is a very serious problem, especially
+                // when that pawn is also blocked.
+                if (   pos.is_chess960()
+                    && (s == relative_square(Us, SQ_A1) || s == relative_square(Us, SQ_H1)))
+                {
+                    Direction d = pawn_push(Us) + (file_of(s) == FILE_A ? EAST : WEST);
+                    if (pos.piece_on(s + d) == make_piece(Us, PAWN))
+                        score -= !pos.empty(s + d + pawn_push(Us))                ? CorneredBishop * 4
+                                : pos.piece_on(s + d + d) == make_piece(Us, PAWN) ? CorneredBishop * 2
+                                                                                  : CorneredBishop;
+                }
             }
         }
 
@@ -602,8 +601,8 @@ namespace {
             Square blockSq = s + Up;
 
             // Adjust bonus based on the king's proximity
-            bonus += make_score(0, (  king_proximity(Them, blockSq) * 5
-                                    - king_proximity(Us,   blockSq) * 2) * w);
+            bonus += make_score(0, (  (king_proximity(Them, blockSq) * 19) / 4
+                                     - king_proximity(Us,   blockSq) *  2) * w);
 
             // If blockSq is not the queening square then consider also a second push
             if (r != RANK_7)
@@ -705,6 +704,9 @@ namespace {
     int outflanking =  distance<File>(pos.square<KING>(WHITE), pos.square<KING>(BLACK))
                      - distance<Rank>(pos.square<KING>(WHITE), pos.square<KING>(BLACK));
 
+    bool infiltration =   rank_of(pos.square<KING>(WHITE)) > RANK_4
+                       || rank_of(pos.square<KING>(BLACK)) < RANK_5;
+
     bool pawnsOnBothFlanks =   (pos.pieces(PAWN) & QueenSide)
                             && (pos.pieces(PAWN) & KingSide);
 
@@ -716,10 +718,11 @@ namespace {
     int complexity =   9 * pe->passed_count()
                     + 11 * pos.count<PAWN>()
                     +  9 * outflanking
+                    + 12 * infiltration
                     + 21 * pawnsOnBothFlanks
                     + 51 * !pos.non_pawn_material()
                     - 43 * almostUnwinnable
-                    - 95 ;
+                    - 100 ;
 
     // Now apply the bonus: note that we find the attacking side by extracting the
     // sign of the midgame or endgame values, and that we carefully cap the bonus
@@ -847,6 +850,9 @@ Value Eval::evaluate(const Position& pos) {
 
 std::string Eval::trace(const Position& pos) {
 
+  if (pos.checkers())
+      return "Total evaluation: none (in check)";
+
   std::memset(scores, 0, sizeof(scores));
 
   pos.this_thread()->contempt = SCORE_ZERO; // Reset any dynamic contempt