Minor cleanup of search.cpp

[stockfish] / src / material.cpp

diff --git a/src/material.cpp b/src/material.cpp
index 114f083171fe748423c83070cb619d853ad44096..c0237e7cac7507f3442977d0ffc153c3058544ef 100644 (file)
--- a/src/material.cpp
+++ b/src/material.cpp
@@ -53,15 +53,10 @@ namespace {
     { 101,  100, -37,   141,  268,    0 }  // Queen
   };
 
-  // PawnSet[pawn count] contains a bonus/malus indexed by number of pawns
-  const int PawnSet[] = {
-    24, -32, 107, -51, 117, -9, -126, -21, 31
-  };
-
   // QueenMinorsImbalance[opp_minor_count] is applied when only one side has a queen.
   // It contains a bonus/malus for the side with the queen.
-  const int QueenMinorsImbalance[16] = { 
-    31, -8, -15, -25, -5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+  const int QueenMinorsImbalance[13] = {
+    31, -8, -15, -25, -5
   };
 
   // Endgame evaluation and scaling functions are accessed directly and not through
@@ -100,9 +95,9 @@ namespace {
 
     const Color Them = (Us == WHITE ? BLACK : WHITE);
 
-    int bonus = PawnSet[pieceCount[Us][PAWN]];
+    int bonus = 0;
 
-    // Second-degree polynomial material imbalance by Tord Romstad
+    // Second-degree polynomial material imbalance, by Tord Romstad
     for (int pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; ++pt1)
     {
         if (!pieceCount[Us][pt1])
@@ -144,7 +139,13 @@ Entry* probe(const Position& pos) {
   std::memset(e, 0, sizeof(Entry));
   e->key = key;
   e->factor[WHITE] = e->factor[BLACK] = (uint8_t)SCALE_FACTOR_NORMAL;
-  e->gamePhase = pos.game_phase();
+
+  Value npm_w = pos.non_pawn_material(WHITE);
+  Value npm_b = pos.non_pawn_material(BLACK);
+  Value npm = std::max(EndgameLimit, std::min(npm_w + npm_b, MidgameLimit));
+
+  // Map total non-pawn material into [PHASE_ENDGAME, PHASE_MIDGAME]
+  e->gamePhase = Phase(((npm - EndgameLimit) * PHASE_MIDGAME) / (MidgameLimit - EndgameLimit));
 
   // Let's look if we have a specialized evaluation function for this particular
   // material configuration. Firstly we look for a fixed configuration one, then
@@ -181,9 +182,6 @@ Entry* probe(const Position& pos) {
         e->scalingFunction[c] = &ScaleKQKRPs[c];
   }
 
-  Value npm_w = pos.non_pawn_material(WHITE);
-  Value npm_b = pos.non_pawn_material(BLACK);
-
   if (npm_w + npm_b == VALUE_ZERO && pos.pieces(PAWN)) // Only pawns on the board
   {
       if (!pos.count<PAWN>(BLACK))