X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=0b687a8d1496e797e22983b36ca7b0819fd92ea8;hp=615763cdcf93007a3e09b42d8a2f8727e31f19c7;hb=45b0aea875860e9f0fe2d0435ee6163906639194;hpb=56d2c3844a210e74ac0c90f9bd32c4c25d058a83

diff --git a/src/position.cpp b/src/position.cpp
index 615763cd..0b687a8d 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -1149,9 +1149,9 @@ void Position::clear() {
   startState.epSquare = SQ_NONE;
   st = &startState;
 
-  for (int i = 0; i < 8; i++)
+  for (int i = 0; i < PIECE_TYPE_NB; i++)
       for (int j = 0; j < 16; j++)
-          pieceList[0][i][j] = pieceList[1][i][j] = SQ_NONE;
+          pieceList[WHITE][i][j] = pieceList[BLACK][i][j] = SQ_NONE;
 }
 
 
@@ -1223,6 +1223,7 @@ Key Position::compute_material_key() const {
 /// game and the endgame. These functions are used to initialize the incremental
 /// scores when a new position is set up, and to verify that the scores are correctly
 /// updated by do_move and undo_move when the program is running in debug mode.
+
 Score Position::compute_psq_score() const {
 
   Score score = SCORE_ZERO;
@@ -1254,21 +1255,14 @@ Value Position::compute_non_pawn_material(Color c) const {
 }
 
 
-/// Position::is_draw() tests whether the position is drawn by material,
-/// repetition, or the 50 moves rule. It does not detect stalemates, this
-/// must be done by the search.
-bool Position::is_draw() const {
+/// Position::is_draw() tests whether the position is drawn by 50 moves rule
+/// or by repetition. It does not detect stalemates.
 
-  // Draw by material?
-  if (   !pieces(PAWN)
-      && (non_pawn_material(WHITE) + non_pawn_material(BLACK) <= BishopValueMg))
-      return true;
+bool Position::is_draw() const {
 
-  // Draw by the 50 moves rule?
   if (st->rule50 > 99 && (!checkers() || MoveList<LEGAL>(*this).size()))
       return true;
 
-  // Draw by repetition?
   int i = 4, e = std::min(st->rule50, st->pliesFromNull);
 
   if (i <= e)
@@ -1279,7 +1273,7 @@ bool Position::is_draw() const {
           stp = stp->previous->previous;
 
           if (stp->key == st->key)
-              return true;
+              return true; // Draw after first repetition
 
           i += 2;