X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fendgame.cpp;h=05de131fb2b26deff9336ddc2137db701752d56e;hp=55e4483dbe84a22c0d456b2a2994fc7e0256ca3d;hb=bc3b148d5712ef9ea00e74d3ff5aea10a4d3cabe;hpb=759b3c79cf94d101163f646b1eb2a9f9c64293ab

diff --git a/src/endgame.cpp b/src/endgame.cpp
index 55e4483d..05de131f 100644
--- a/src/endgame.cpp
+++ b/src/endgame.cpp
@@ -86,30 +86,6 @@ namespace {
 } // namespace
 
 
-/// Endgames members definitions
-
-Endgames::Endgames() {
-
-  add<KPK>("KPK");
-  add<KNNK>("KNNK");
-  add<KBNK>("KBNK");
-  add<KRKP>("KRKP");
-  add<KRKB>("KRKB");
-  add<KRKN>("KRKN");
-  add<KQKP>("KQKP");
-  add<KQKR>("KQKR");
-
-  add<KNPK>("KNPK");
-  add<KNPKB>("KNPKB");
-  add<KRPKR>("KRPKR");
-  add<KRPKB>("KRPKB");
-  add<KBPKB>("KBPKB");
-  add<KBPKN>("KBPKN");
-  add<KBPPKB>("KBPPKB");
-  add<KRPPKRP>("KRPPKRP");
-}
-
-
 /// Mate with KX vs K. This function is used to evaluate positions with
 /// king and plenty of material vs a lone king. It simply gives the
 /// attacking side a bonus for driving the defending king towards the edge
@@ -214,7 +190,7 @@ Value Endgame<KRKP>::operator()(const Position& pos) const {
   Value result;
 
   // If the stronger side's king is in front of the pawn, it's a win
-  if (wksq < psq && file_of(wksq) == file_of(psq))
+  if (forward_file_bb(WHITE, wksq) & psq)
       result = RookValueEg - distance(wksq, psq);
 
   // If the weaker side's king is too far from the pawn and the rook,
@@ -240,7 +216,7 @@ Value Endgame<KRKP>::operator()(const Position& pos) const {
 }
 
 
-/// KR vs KB. This is very simple, and always returns drawish scores.  The
+/// KR vs KB. This is very simple, and always returns drawish scores. The
 /// score is slightly bigger when the defending king is close to the edge.
 template<>
 Value Endgame<KRKB>::operator()(const Position& pos) const {
@@ -631,29 +607,8 @@ ScaleFactor Endgame<KBPKB>::operator()(const Position& pos) const {
 
   // Case 2: Opposite colored bishops
   if (opposite_colors(strongBishopSq, weakBishopSq))
-  {
-      // We assume that the position is drawn in the following three situations:
-      //
-      //   a. The pawn is on rank 5 or further back.
-      //   b. The defending king is somewhere in the pawn's path.
-      //   c. The defending bishop attacks some square along the pawn's path,
-      //      and is at least three squares away from the pawn.
-      //
-      // These rules are probably not perfect, but in practice they work
-      // reasonably well.
-
-      if (relative_rank(strongSide, pawnSq) <= RANK_5)
-          return SCALE_FACTOR_DRAW;
-
-      Bitboard path = forward_file_bb(strongSide, pawnSq);
-
-      if (path & pos.pieces(weakSide, KING))
-          return SCALE_FACTOR_DRAW;
+      return SCALE_FACTOR_DRAW;
 
-      if (  (pos.attacks_from<BISHOP>(weakBishopSq) & path)
-          && distance(weakBishopSq, pawnSq) >= 3)
-          return SCALE_FACTOR_DRAW;
-  }
   return SCALE_FACTOR_NONE;
 }