X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmovepick.cpp;h=b115e8ffb1a9c3b9a6a1c6371ffef62067eea3e3;hb=a56e1c662c3aa04b88744d62790daa10c01cdc78;hp=4ab5e892079beba61af7d70a8d91610d59b54619;hpb=4397e6c03e72881a0a477c61c7d17c040c6fdb92;p=stockfish

diff --git a/src/movepick.cpp b/src/movepick.cpp
index 4ab5e892..b115e8ff 100644
--- a/src/movepick.cpp
+++ b/src/movepick.cpp
@@ -39,7 +39,7 @@ namespace {
 
   /// Variables
 
-  MovePicker::MovegenPhase PhaseTable[32];  
+  MovePicker::MovegenPhase PhaseTable[32];
   int MainSearchPhaseIndex;
   int EvasionsPhaseIndex;
   int QsearchWithChecksPhaseIndex;
@@ -62,7 +62,7 @@ namespace {
 /// move ordering is at the current node.
 
 MovePicker::MovePicker(const Position& p, bool pvnode, Move ttm, Move mk,
-                       Move k1, Move k2, Depth d) : pos(p) {  
+                       Move k1, Move k2, Depth d) : pos(p) {
   pvNode = pvnode;
   ttMove = ttm;
   mateKiller = (mk == ttm)? MOVE_NONE : mk;
@@ -147,13 +147,13 @@ Move MovePicker::get_next_move() {
         break;
 
     case PH_EVASIONS:
-        assert(pos.is_check());      
+        assert(pos.is_check());
         numOfMoves = generate_evasions(pos, moves);
         score_evasions();
         movesPicked = 0;
         break;
 
-    case PH_QCAPTURES:      
+    case PH_QCAPTURES:
         numOfMoves = generate_captures(pos, moves);
         score_qcaptures();
         movesPicked = 0;
@@ -172,8 +172,6 @@ Move MovePicker::get_next_move() {
         return MOVE_NONE;
     }
   }
-  assert(false);
-  return MOVE_NONE;
 }
 
 
@@ -192,7 +190,7 @@ Move MovePicker::get_next_move(Lock &lock) {
    if (m == MOVE_NONE)
        finished = true;
 
-   lock_release(&lock);   
+   lock_release(&lock);
    return m;
 }
 
@@ -209,35 +207,51 @@ void MovePicker::score_captures() {
   // capture, capturing a more valuable (but sufficiently defended) piece
   // first usually doesn't hurt.  The opponent will have to recapture, and
   // the hanging piece will still be hanging (except in the unusual cases
-  // where it is possible to recapture with the hanging piece).  Exchanging
+  // where it is possible to recapture with the hanging piece). Exchanging
   // big pieces before capturing a hanging piece probably helps to reduce
   // the subtree size.
+  Move m;
+  int seeValue;
+
   for (int i = 0; i < numOfMoves; i++)
   {
-      int seeValue = pos.see(moves[i].move);
+      m = moves[i].move;
+      seeValue = pos.see(m);
       if (seeValue >= 0)
       {
-          if (move_promotion(moves[i].move))
+          if (move_promotion(m))
               moves[i].score = QueenValueMidgame;
           else
-              moves[i].score = int(pos.midgame_value_of_piece_on(move_to(moves[i].move)))
-                              -int(pos.type_of_piece_on(move_from(moves[i].move)));
+              moves[i].score = int(pos.midgame_value_of_piece_on(move_to(m)))
+                              -int(pos.type_of_piece_on(move_from(m)));
       } else
           moves[i].score = seeValue;
   }
 }
 
 void MovePicker::score_noncaptures() {
-
-  for (int i = 0; i < numOfMoves; i++)
-  {
-      Move m = moves[i].move;
-      if (m == killer1)
-          moves[i].score = HistoryMax + 2;
-      else if (m == killer2)
-          moves[i].score = HistoryMax + 1;
-      else
-         moves[i].score = H.move_ordering_score(pos.piece_on(move_from(m)), m);
+  // First score by history, when no history is available then use
+  // piece/square tables values. This seems to be better then a
+  // random choice when we don't have an history for any move.
+  Move m;
+  int hs;
+
+  for (int i = 0; i < numOfMoves; i++)
+  {
+      m = moves[i].move;
+
+      if (m == killer1)
+          hs = HistoryMax + 2;
+      else if (m == killer2)
+          hs = HistoryMax + 1;
+      else
+          hs = H.move_ordering_score(pos.piece_on(move_from(m)), m);
+
+      // Ensure moves in history are always sorted as first
+      if (hs > 0)
+          hs += 1000;
+
+      moves[i].score = hs + pos.mg_pst_delta(m);
   }
 }
 
@@ -268,25 +282,25 @@ void MovePicker::score_qcaptures() {
           moves[i].score = QueenValueMidgame;
       else
           moves[i].score = int(pos.midgame_value_of_piece_on(move_to(m)))
-                          -int(pos.midgame_value_of_piece_on(move_to(m))) / 64;
+                          -int(pos.type_of_piece_on(move_from(m)));
   }
 }
 
 
-/// find_best_index() loops across the moves and returns index of
-/// the highest scored one.
-
-int MovePicker::find_best_index() {
-
-  int bestScore = -10000000, bestIndex = -1;
-
-  for (int i = movesPicked; i < numOfMoves; i++)
-      if (moves[i].score > bestScore)
-      {
-          bestIndex = i;
-          bestScore = moves[i].score;
-      }
-  return bestIndex;
+/// find_best_index() loops across the moves and returns index of
+/// the highest scored one.
+
+int MovePicker::find_best_index() {
+
+  int bestScore = -10000000, bestIndex = -1;
+
+  for (int i = movesPicked; i < numOfMoves; i++)
+      if (moves[i].score > bestScore)
+      {
+          bestIndex = i;
+          bestScore = moves[i].score;
+      }
+  return bestIndex;
 }
 
 
@@ -435,8 +449,8 @@ Move MovePicker::pick_move_from_list() {
 }
 
 
-/// MovePicker::current_move_type() returns the type of the just
-/// picked next move. It can be used in search to further differentiate
+/// MovePicker::current_move_type() returns the type of the just
+/// picked next move. It can be used in search to further differentiate
 /// according to the current move type: capture, non capture, escape, etc.
 MovePicker::MovegenPhase MovePicker::current_move_type() const {