X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fposition.cpp;h=1a8c7e00d6a0bc24af2e44c395a70fb9eb6c1d4b;hp=1b2defa54662a34718bb46c79e40ae9abffbe595;hb=d3608c4e79a29110f4c4a369d7207c6dd8e01f34;hpb=d23454854e72e1311363a8c98cd58a5d44c427f9 diff --git a/src/position.cpp b/src/position.cpp index 1b2defa5..1a8c7e00 100644 --- a/src/position.cpp +++ b/src/position.cpp @@ -408,8 +408,8 @@ const string Position::pretty(Move move) const { ss << square_to_string(pop_lsb(&b)) << " "; ss << "\nLegal moves: "; - for (MoveList ml(*this); !ml.end(); ++ml) - ss << move_to_san(*const_cast(this), ml.move()) << " "; + for (MoveList it(*this); *it; ++it) + ss << move_to_san(*const_cast(this), *it) << " "; return ss.str(); } @@ -1129,10 +1129,10 @@ void Position::undo_null_move() { /// Position::see() is a static exchange evaluator: It tries to estimate the -/// material gain or loss resulting from a move. There are three versions of -/// this function: One which takes a destination square as input, one takes a -/// move, and one which takes a 'from' and a 'to' square. The function does -/// not yet understand promotions captures. +/// material gain or loss resulting from a move. Parameter 'asymmThreshold' takes +/// tempi into account. If the side who initiated the capturing sequence does the +/// last capture, he loses a tempo and if the result is below 'asymmThreshold' +/// the capturing sequence is considered bad. int Position::see_sign(Move m) const { @@ -1147,22 +1147,7 @@ int Position::see_sign(Move m) const { return see(m); } -int Position::see(Move m) const { - return do_see(m, 0); -} - -/// Position::see_asymm() takes tempi into account. -/// If the side who initiated the capturing sequence does the last capture, -/// he loses a tempo. In this case if the result is below asymmThreshold -/// the capturing sequence is considered bad. - -int Position::see_asymm(Move m, int asymmThreshold) const -{ - return do_see(m, asymmThreshold); -} - -template -int Position::do_see(Move m, int asymmThreshold) const { +int Position::see(Move m, int asymmThreshold) const { Square from, to; Bitboard occupied, attackers, stmAttackers; @@ -1240,16 +1225,13 @@ int Position::do_see(Move m, int asymmThreshold) const { } while (stmAttackers); // If we are doing asymmetric SEE evaluation and the same side does the first - // and the last capture, he loses a tempo and gain must be at least worth "asymmThreshold". - // If not, we replace the score with a very low value, before negamaxing. - if (Asymmetric) - { - for (int i = 0; i < slIndex ; i += 2) - { + // and the last capture, he loses a tempo and gain must be at least worth + // 'asymmThreshold', otherwise we replace the score with a very low value, + // before negamaxing. + if (asymmThreshold) + for (int i = 0; i < slIndex; i += 2) if (swapList[i] < asymmThreshold) - swapList[i] = - QueenValueMg * 16; - } - } + swapList[i] = - QueenValueMg * 16; // Having built the swap list, we negamax through it to find the best // achievable score from the point of view of the side to move. @@ -1394,7 +1376,6 @@ 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. -template bool Position::is_draw() const { // Draw by material? @@ -1407,33 +1388,26 @@ bool Position::is_draw() const { return true; // Draw by repetition? - if (!SkipRepetition) - { - int i = 4, e = std::min(st->rule50, st->pliesFromNull); + int i = 4, e = std::min(st->rule50, st->pliesFromNull); - if (i <= e) - { - StateInfo* stp = st->previous->previous; + if (i <= e) + { + StateInfo* stp = st->previous->previous; - do { - stp = stp->previous->previous; + do { + stp = stp->previous->previous; - if (stp->key == st->key) - return true; + if (stp->key == st->key) + return true; - i += 2; + i += 2; - } while (i <= e); - } + } while (i <= e); } return false; } -// Explicit template instantiations -template bool Position::is_draw() const; -template bool Position::is_draw() const; - /// Position::flip() flips position with the white and black sides reversed. This /// is only useful for debugging especially for finding evaluation symmetry bugs.