Revert dynamic draw value

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index 01d2a387e3aefa2592ff476d824063d41e1f81f4..72ec79e71f3e95539d0b05776147d3d51a040d41 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -43,7 +43,7 @@ namespace Search {
   std::vector<RootMove> RootMoves;
   Position RootPos;
   Color RootColor;
-  Time::point SearchTime, IterationTime;
+  Time::point SearchTime;
   StateStackPtr SetupStates;
 }
 
@@ -185,6 +185,10 @@ void Search::think() {
   RootColor = RootPos.side_to_move();
   TimeMgr.init(Limits, RootPos.game_ply(), RootColor);
 
+  int cf = Options["Contempt Factor"] * PawnValueMg / 100; // From centipawns
+  DrawValue[ RootColor] = VALUE_DRAW - Value(cf);
+  DrawValue[~RootColor] = VALUE_DRAW + Value(cf);
+
   if (RootMoves.empty())
   {
       RootMoves.push_back(MOVE_NONE);
@@ -206,16 +210,6 @@ void Search::think() {
       }
   }
 
-  if (Options["Contempt Factor"] && !Options["UCI_AnalyseMode"])
-  {
-      int cf = Options["Contempt Factor"] * PawnValueMg / 100; // From centipawns
-      cf = cf * Material::game_phase(RootPos) / PHASE_MIDGAME; // Scale down with phase
-      DrawValue[ RootColor] = VALUE_DRAW - Value(cf);
-      DrawValue[~RootColor] = VALUE_DRAW + Value(cf);
-  }
-  else
-      DrawValue[WHITE] = DrawValue[BLACK] = VALUE_DRAW;
-
   if (Options["Write Search Log"])
   {
       Log log(Options["Search Log Filename"]);
@@ -397,7 +391,7 @@ namespace {
                 sync_cout << uci_pv(pos, depth, alpha, beta) << sync_endl;
         }
 
-        IterationTime = Time::now() - SearchTime;
+        Time::point iterationTime = Time::now() - SearchTime;
 
         // If skill levels are enabled and time is up, pick a sub-optimal best move
         if (skill.enabled() && skill.time_to_pick(depth))
@@ -432,7 +426,7 @@ namespace {
             // Stop the search if only one legal move is available or all
             // of the available time has been used.
             if (   RootMoves.size() == 1
-                || IterationTime > TimeMgr.available_time() )
+                || iterationTime > TimeMgr.available_time() )
                 stop = true;
 
             if (stop)
@@ -668,7 +662,7 @@ namespace {
         && !ss->skipNullMove
         &&  abs(beta) < VALUE_MATE_IN_MAX_PLY)
     {
-        Value rbeta = beta + 200;
+        Value rbeta = std::min(beta + 200, VALUE_INFINITE);
         Depth rdepth = depth - ONE_PLY - 3 * ONE_PLY;
 
         assert(rdepth >= ONE_PLY);
@@ -779,7 +773,7 @@ moves_loop: // When in check and at SpNode search starts from here
                  || pos.advanced_pawn_push(move);
 
       // Step 12. Extend checks
-      if (givesCheck && pos.see_sign(move) >= 0)
+      if (givesCheck && pos.see_sign(move) >= VALUE_ZERO)
           ext = ONE_PLY;
 
       // Singular extension search. If all moves but one fail low on a search of
@@ -850,7 +844,7 @@ moves_loop: // When in check and at SpNode search starts from here
           }
 
           // Prune moves with negative SEE at low depths
-          if (predictedDepth < 4 * ONE_PLY && pos.see_sign(move) < 0)
+          if (predictedDepth < 4 * ONE_PLY && pos.see_sign(move) < VALUE_ZERO)
           {
               if (SpNode)
                   splitPoint->mutex.lock();
@@ -1175,7 +1169,7 @@ moves_loop: // When in check and at SpNode search starts from here
               continue;
           }
 
-          if (futilityBase < beta && pos.see(move) <= 0)
+          if (futilityBase < beta && pos.see(move) <= VALUE_ZERO)
           {
               bestValue = std::max(bestValue, futilityBase);
               continue;
@@ -1193,7 +1187,7 @@ moves_loop: // When in check and at SpNode search starts from here
           && (!InCheck || evasionPrunable)
           &&  move != ttMove
           &&  type_of(move) != PROMOTION
-          &&  pos.see_sign(move) < 0)
+          &&  pos.see_sign(move) < VALUE_ZERO)
           continue;
 
       // Check for legality just before making the move
@@ -1627,8 +1621,7 @@ void check_time() {
   Time::point elapsed = Time::now() - SearchTime;
   bool stillAtFirstMove =    Signals.firstRootMove
                          && !Signals.failedLowAtRoot
-                         &&  elapsed > TimeMgr.available_time()
-                         &&  elapsed > IterationTime * 1.4;
+                         &&  elapsed > TimeMgr.available_time() * 75 / 100;
 
   bool noMoreTime =   elapsed > TimeMgr.maximum_time() - 2 * TimerThread::Resolution
                    || stillAtFirstMove;