X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmaterial.cpp;h=9e46d05d4e74ffc237cc081458e628ffef9ba265;hp=89147352ffe8b62c310a3dd2679806f7cb8fc6f8;hb=698b645e10388366ca0400bc05c21af98b7703b2;hpb=d91079d4b02b410702dda082d5c489847f067a35

diff --git a/src/material.cpp b/src/material.cpp
index 89147352..9e46d05d 100644
--- a/src/material.cpp
+++ b/src/material.cpp
@@ -115,6 +115,17 @@ namespace {
 
         value += pc * v;
     }
+
+    // Queen vs. 3 minors slightly favours the minors
+    if (pieceCount[Us][QUEEN] == 1 && pieceCount[Them][QUEEN] == 0)
+    {
+        int n = pieceCount[Them][KNIGHT] - pieceCount[Us][KNIGHT];
+        int b = pieceCount[Them][BISHOP] - pieceCount[Us][BISHOP];
+
+        if ((n == 2 && b == 1) || (n == 1 && b == 2))
+            value -= 66 * 16;
+    }
+
     return value;
   }
 
@@ -174,7 +185,7 @@ Entry* probe(const Position& pos, Table& entries, Endgames& endgames) {
       return e;
   }
 
-  // Generic scaling functions that refer to more then one material
+  // Generic scaling functions that refer to more than one material
   // distribution. They should be probed after the specialized ones.
   // Note that these ones don't return after setting the function.
   if (is_KBPsKs<WHITE>(pos))
@@ -217,24 +228,16 @@ Entry* probe(const Position& pos, Table& entries, Endgames& endgames) {
   // catches some trivial draws like KK, KBK and KNK and gives a very drawish
   // scale factor for cases such as KRKBP and KmmKm (except for KBBKN).
   if (!pos.count<PAWN>(WHITE) && npm_w - npm_b <= BishopValueMg)
-  {
-      e->factor[WHITE] = npm_w < RookValueMg ? 0 : npm_b <= BishopValueMg ? 4 : 12;
-  }
+      e->factor[WHITE] = uint8_t(npm_w < RookValueMg ? SCALE_FACTOR_DRAW : npm_b <= BishopValueMg ? 4 : 12);
 
   if (!pos.count<PAWN>(BLACK) && npm_b - npm_w <= BishopValueMg)
-  {
-      e->factor[BLACK] = npm_b < RookValueMg ? 0 : npm_w <= BishopValueMg ? 4 : 12;
-  }
+      e->factor[BLACK] = uint8_t(npm_b < RookValueMg ? SCALE_FACTOR_DRAW : npm_w <= BishopValueMg ? 4 : 12);
 
   if (pos.count<PAWN>(WHITE) == 1 && npm_w - npm_b <= BishopValueMg)
-  {
       e->factor[WHITE] = (uint8_t) SCALE_FACTOR_ONEPAWN;
-  }
 
   if (pos.count<PAWN>(BLACK) == 1 && npm_b - npm_w <= BishopValueMg)
-  {
       e->factor[BLACK] = (uint8_t) SCALE_FACTOR_ONEPAWN;
-  }
 
   // Compute the space weight
   if (npm_w + npm_b >= 2 * QueenValueMg + 4 * RookValueMg + 2 * KnightValueMg)