Add FEN support, solves issue #17

hans-ekbrand · Jan 29, 2023 · 539aae2 · 539aae2
1 parent b34aa83
commit 539aae2
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Showing 2 changed files with 9 additions and 4 deletions.
diff --git a/libs/lczero-common b/libs/lczero-common
diff --git a/src/mcts/auxengine.cc b/src/mcts/auxengine.cc
@@ -1255,9 +1255,14 @@ void Search::DoAuxEngine(Node* n, int index){
     my_board.Mirror();
   }
 
-  if (params_.GetAuxEngineVerbosity() >= 9) LOGFILE << "add position=" << s << " for the helper to explore";
-  s = "position startpos moves " + s;
-
+  // In analysis mode, Leela can be given a FEN in which case we cannot supply the history of the position, which in turn means we have to give the helper a FEN too.
+  if(ChessBoard::kStartposBoard == my_board){
+    s = "position startpos moves " + s;
+  } else {
+    PositionHistory ph = played_history_;
+    s = "position fen " + GetFen(ph.Last()) + " moves " + s;
+  }
+
   // 1. Only start the engines if we can aquire the auxengine_stopped_mutex
   // 2. Only send anything to the engines if we have aquired that mutex