X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fsearch.cpp;h=eb3fc82a40862c24ec907b8bdd53c6d98a34ca08;hp=da22c5cff066f505ba5eed5537904fc0ed97d32b;hb=708cb311a040ca8c676524025c9d72ed4c632267;hpb=b8cfc255d46113573a0869e56224a382c74dfcdc

diff --git a/src/search.cpp b/src/search.cpp
index da22c5cf..eb3fc82a 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -185,6 +185,11 @@ void Search::think() {
   RootColor = RootPos.side_to_move();
   TimeMgr.init(Limits, RootPos.game_ply(), RootColor);
 
+  // Dynamic draw value: try to avoid repetition draws at early midgame
+  int cf = std::max(70 - RootPos.game_ply(), 0);
+  DrawValue[ RootColor] = VALUE_DRAW - Value(cf);
+  DrawValue[~RootColor] = VALUE_DRAW + Value(cf);
+
   if (RootMoves.empty())
   {
       RootMoves.push_back(MOVE_NONE);
@@ -206,16 +211,6 @@ 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"]);
@@ -668,7 +663,7 @@ 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);