Make contempt dependent on current score and reduce default contempt …

…by 10%. Bench: 5712242
official-stockfish · Feb 5, 2018 · cee1828 · cee1828
1 parent 414a3e6
commit cee1828
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Showing 2 changed files with 11 additions and 6 deletions.
diff --git a/src/search.cpp b/src/search.cpp
@@ -192,11 +192,6 @@ void MainThread::search() {
   Time.init(Limits, us, rootPos.game_ply());
   TT.new_search();
 
-  int contempt = Options["Contempt"] * PawnValueEg / 100; // From centipawns
-
-  Eval::Contempt = (us == WHITE ?  make_score(contempt, contempt / 2)
-                                : -make_score(contempt, contempt / 2));
-
   if (rootMoves.empty())
   {
       rootMoves.emplace_back(MOVE_NONE);
@@ -307,6 +302,10 @@ void Thread::search() {
 
   multiPV = std::min(multiPV, rootMoves.size());
 
+  int contempt = Options["Contempt"] * PawnValueEg / 100; // From centipawns
+  Eval::Contempt = (rootPos.side_to_move() == WHITE ?  make_score(contempt, contempt / 2)
+                                                    : -make_score(contempt, contempt / 2));
+
   // Iterative deepening loop until requested to stop or the target depth is reached
   while (   (rootDepth += ONE_PLY) < DEPTH_MAX
          && !Threads.stop
@@ -341,6 +340,12 @@ void Thread::search() {
               delta = Value(18);
               alpha = std::max(rootMoves[PVIdx].previousScore - delta,-VALUE_INFINITE);
               beta  = std::min(rootMoves[PVIdx].previousScore + delta, VALUE_INFINITE);
+
+              // Adjust contempt based on current situation
+              contempt = Options["Contempt"] * PawnValueEg / 100 + bestValue/10; // From centipawns
+              Eval::Contempt = (rootPos.side_to_move() == WHITE ?  make_score(contempt, contempt / 2)
+                                                                : -make_score(contempt, contempt / 2));
+
           }
 
           // Start with a small aspiration window and, in the case of a fail

diff --git a/src/ucioption.cpp b/src/ucioption.cpp
@@ -59,7 +59,7 @@ void init(OptionsMap& o) {
   const int MaxHashMB = Is64Bit ? 131072 : 2048;
 
   o["Debug Log File"]        << Option("", on_logger);
-  o["Contempt"]              << Option(20, -100, 100);
+  o["Contempt"]              << Option(18, -100, 100);
   o["Threads"]               << Option(1, 1, 512, on_threads);
   o["Hash"]                  << Option(16, 1, MaxHashMB, on_hash_size);
   o["Clear Hash"]            << Option(on_clear_hash);