X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fendgame.cpp;h=44a34d607fb69676fd12b662f2b56f2c18e26003;hp=348feecf70bf5e170211460a23145a55749610dd;hb=b5d5646c840d63710552fdaf2521a054dd3b8a18;hpb=324ca87affc4959f7017e83437fb06b6e770449c
diff --git a/src/endgame.cpp b/src/endgame.cpp
index 348feecf..44a34d60 100644
--- a/src/endgame.cpp
+++ b/src/endgame.cpp
@@ -17,20 +17,15 @@
along with this program. If not, see .
*/
-
-////
-//// Includes
-////
-
#include
#include "bitcount.h"
#include "endgame.h"
+#include "pawns.h"
+using std::string;
-////
-//// Local definitions
-////
+extern uint32_t probe_kpk_bitbase(Square wksq, Square wpsq, Square bksq, Color stm);
namespace {
@@ -68,9 +63,6 @@ namespace {
// and knight in KR vs KN endgames.
const int KRKNKingKnightDistancePenalty[8] = { 0, 0, 4, 10, 20, 32, 48, 70 };
- // Bitbase for KP vs K
- uint8_t KPKBitbase[24576];
-
// Various inline functions for accessing the above arrays
inline Value mate_table(Square s) {
return Value(MateTable[s]);
@@ -88,32 +80,102 @@ namespace {
return Value(KRKNKingKnightDistancePenalty[d]);
}
- // Function for probing the KP vs K bitbase
- int probe_kpk(Square wksq, Square wpsq, Square bksq, Color stm);
+ // Build corresponding key for the opposite color: "KBPKN" -> "KNKBP"
+ const string swapColors(const string& keyCode) {
+
+ size_t idx = keyCode.find('K', 1);
+ return keyCode.substr(idx) + keyCode.substr(0, idx);
+ }
+
+ // Build up a fen string with the given pieces, note that the fen string
+ // could be of an illegal position.
+ Key buildKey(const string& keyCode) {
+
+ assert(keyCode.length() > 0 && keyCode.length() < 8);
+ assert(keyCode[0] == 'K');
+
+ string fen;
+ bool upcase = false;
+
+ for (size_t i = 0; i < keyCode.length(); i++)
+ {
+ if (keyCode[i] == 'K')
+ upcase = !upcase;
+
+ fen += char(upcase ? toupper(keyCode[i]) : tolower(keyCode[i]));
+ }
+ fen += char(8 - keyCode.length() + '0');
+ fen += "/8/8/8/8/8/8/8 w - -";
+ return Position(fen, false, 0).get_material_key();
+ }
+
+ typedef EndgameBase EF;
+ typedef EndgameBase SF;
+
+} // namespace
+
+
+/// Endgames member definitions
+
+template<> const Endgames::EFMap& Endgames::get() const { return maps.first; }
+template<> const Endgames::SFMap& Endgames::get() const { return maps.second; }
+
+Endgames::Endgames() {
+
+ add >("KNNK");
+ add >("KPK");
+ add >("KBNK");
+ add >("KRKP");
+ add >("KRKB");
+ add >("KRKN");
+ add >("KQKR");
+ add >("KBBKN");
+ add >("KNPK");
+ add >("KRPKR");
+ add >("KBPKB");
+ add >("KBPPKB");
+ add >("KBPKN");
+ add >("KRPPKRP");
}
+Endgames::~Endgames() {
-////
-//// Functions
-////
+ for (EFMap::const_iterator it = get().begin(); it != get().end(); ++it)
+ delete it->second;
-/// init_bitbases() is called during program initialization, and simply loads
-/// bitbases from disk into memory. At the moment, there is only the bitbase
-/// for KP vs K, but we may decide to add other bitbases later.
-extern void generate_kpk_bitbase(uint8_t bitbase[]);
+ for (SFMap::const_iterator it = get().begin(); it != get().end(); ++it)
+ delete it->second;
+}
+
+template
+void Endgames::add(const string& keyCode) {
+
+ typedef typename T::Base F;
+ typedef std::map M;
-void init_bitbases() {
- generate_kpk_bitbase(KPKBitbase);
+ const_cast(get()).insert(std::pair(buildKey(keyCode), new T(WHITE)));
+ const_cast(get()).insert(std::pair(buildKey(swapColors(keyCode)), new T(BLACK)));
}
+template
+T* Endgames::get(Key key) const {
+
+ typename std::map::const_iterator it = get().find(key);
+ return it != get().end() ? it->second : NULL;
+}
+
+// Explicit template instantiations
+template EF* Endgames::get(Key key) const;
+template SF* Endgames::get(Key key) const;
+
/// Mate with KX vs K. This function is used to evaluate positions with
/// King and plenty of material vs a lone king. It simply gives the
/// attacking side a bonus for driving the defending king towards the edge
/// of the board, and for keeping the distance between the two kings small.
template<>
-Value EvaluationFunction::apply(const Position& pos) const {
+Value Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO);
assert(pos.piece_count(weakerSide, PAWN) == VALUE_ZERO);
@@ -139,7 +201,7 @@ Value EvaluationFunction::apply(const Position& pos) const {
/// Mate with KBN vs K. This is similar to KX vs K, but we have to drive the
/// defending king towards a corner square of the right color.
template<>
-Value EvaluationFunction::apply(const Position& pos) const {
+Value Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO);
assert(pos.piece_count(weakerSide, PAWN) == VALUE_ZERO);
@@ -171,7 +233,7 @@ Value EvaluationFunction::apply(const Position& pos) const {
/// KP vs K. This endgame is evaluated with the help of a bitbase.
template<>
-Value EvaluationFunction::apply(const Position& pos) const {
+Value Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == VALUE_ZERO);
assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO);
@@ -203,7 +265,7 @@ Value EvaluationFunction::apply(const Position& pos) const {
wpsq = flop_square(wpsq);
}
- if (!probe_kpk(wksq, wpsq, bksq, stm))
+ if (!probe_kpk_bitbase(wksq, wpsq, bksq, stm))
return VALUE_DRAW;
Value result = VALUE_KNOWN_WIN
@@ -219,7 +281,7 @@ Value EvaluationFunction::apply(const Position& pos) const {
/// far advanced with support of the king, while the attacking king is far
/// away.
template<>
-Value EvaluationFunction::apply(const Position& pos) const {
+Value Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == RookValueMidgame);
assert(pos.piece_count(strongerSide, PAWN) == 0);
@@ -276,7 +338,7 @@ Value EvaluationFunction::apply(const Position& pos) const {
/// KR vs KB. This is very simple, and always returns drawish scores. The
/// score is slightly bigger when the defending king is close to the edge.
template<>
-Value EvaluationFunction::apply(const Position& pos) const {
+Value Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == RookValueMidgame);
assert(pos.piece_count(strongerSide, PAWN) == 0);
@@ -292,7 +354,7 @@ Value EvaluationFunction::apply(const Position& pos) const {
/// KR vs KN. The attacking side has slightly better winning chances than
/// in KR vs KB, particularly if the king and the knight are far apart.
template<>
-Value EvaluationFunction::apply(const Position& pos) const {
+Value Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == RookValueMidgame);
assert(pos.piece_count(strongerSide, PAWN) == 0);
@@ -318,7 +380,7 @@ Value EvaluationFunction::apply(const Position& pos) const {
/// for the defending side in the search, this is usually sufficient to be
/// able to win KQ vs KR.
template<>
-Value EvaluationFunction::apply(const Position& pos) const {
+Value Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == QueenValueMidgame);
assert(pos.piece_count(strongerSide, PAWN) == 0);
@@ -337,7 +399,7 @@ Value EvaluationFunction::apply(const Position& pos) const {
}
template<>
-Value EvaluationFunction::apply(const Position& pos) const {
+Value Endgame::apply(const Position& pos) const {
assert(pos.piece_count(strongerSide, BISHOP) == 2);
assert(pos.non_pawn_material(strongerSide) == 2*BishopValueMidgame);
@@ -366,12 +428,12 @@ Value EvaluationFunction::apply(const Position& pos) const {
/// K and two minors vs K and one or two minors or K and two knights against
/// king alone are always draw.
template<>
-Value EvaluationFunction::apply(const Position&) const {
+Value Endgame::apply(const Position&) const {
return VALUE_DRAW;
}
template<>
-Value EvaluationFunction::apply(const Position&) const {
+Value Endgame::apply(const Position&) const {
return VALUE_DRAW;
}
@@ -381,7 +443,7 @@ Value EvaluationFunction::apply(const Position&) const {
/// returned. If not, the return value is SCALE_FACTOR_NONE, i.e. no scaling
/// will be used.
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == BishopValueMidgame);
assert(pos.piece_count(strongerSide, BISHOP) == 1);
@@ -402,7 +464,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
Square kingSq = pos.king_square(weakerSide);
if ( opposite_color_squares(queeningSq, bishopSq)
- && file_distance(square_file(kingSq), pawnFile) <= 1)
+ && abs(square_file(kingSq) - pawnFile) <= 1)
{
// The bishop has the wrong color, and the defending king is on the
// file of the pawn(s) or the neighboring file. Find the rank of the
@@ -435,7 +497,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
/// It tests for fortress draws with a rook on the third rank defended by
/// a pawn.
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == QueenValueMidgame);
assert(pos.piece_count(strongerSide, QUEEN) == 1);
@@ -466,7 +528,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
/// It would also be nice to rewrite the actual code for this function,
/// which is mostly copied from Glaurung 1.x, and not very pretty.
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == RookValueMidgame);
assert(pos.piece_count(strongerSide, PAWN) == 1);
@@ -584,7 +646,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
/// single pattern: If the stronger side has no pawns and the defending king
/// is actively placed, the position is drawish.
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == RookValueMidgame);
assert(pos.piece_count(strongerSide, PAWN) == 2);
@@ -623,7 +685,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
/// against king. There is just a single rule here: If all pawns are on
/// the same rook file and are blocked by the defending king, it's a draw.
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == VALUE_ZERO);
assert(pos.piece_count(strongerSide, PAWN) >= 2);
@@ -661,7 +723,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
/// it's a draw. If the two bishops have opposite color, it's almost always
/// a draw.
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == BishopValueMidgame);
assert(pos.piece_count(strongerSide, BISHOP) == 1);
@@ -716,7 +778,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
/// KBPPKBScalingFunction scales KBPP vs KB endgames. It detects a few basic
/// draws with opposite-colored bishops.
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == BishopValueMidgame);
assert(pos.piece_count(strongerSide, BISHOP) == 1);
@@ -769,7 +831,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
&& opposite_color_squares(ksq, wbsq)
&& ( bbsq == blockSq2
|| (pos.attacks_from(blockSq2) & pos.pieces(BISHOP, weakerSide))
- || rank_distance(r1, r2) >= 2))
+ || abs(r1 - r2) >= 2))
return SCALE_FACTOR_ZERO;
else if ( ksq == blockSq2
@@ -792,7 +854,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
/// square of the king is not of the same color as the stronger side's bishop,
/// it's a draw.
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == BishopValueMidgame);
assert(pos.piece_count(strongerSide, BISHOP) == 1);
@@ -819,7 +881,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
/// If the pawn is a rook pawn on the 7th rank and the defending king prevents
/// the pawn from advancing, the position is drawn.
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == KnightValueMidgame);
assert(pos.piece_count(strongerSide, KNIGHT) == 1);
@@ -849,7 +911,7 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
/// advanced and not on a rook file; in this case it is often possible to win
/// (e.g. 8/4k3/3p4/3P4/6K1/8/8/8 w - - 0 1).
template<>
-ScaleFactor ScalingFunction::apply(const Position& pos) const {
+ScaleFactor Endgame::apply(const Position& pos) const {
assert(pos.non_pawn_material(strongerSide) == VALUE_ZERO);
assert(pos.non_pawn_material(weakerSide) == VALUE_ZERO);
@@ -889,21 +951,5 @@ ScaleFactor ScalingFunction::apply(const Position& pos) const {
// Probe the KPK bitbase with the weakest side's pawn removed. If it's a
// draw, it's probably at least a draw even with the pawn.
- return probe_kpk(wksq, wpsq, bksq, stm) ? SCALE_FACTOR_NONE : SCALE_FACTOR_ZERO;
-}
-
-
-namespace {
-
- // Probe the KP vs K bitbase
-
- int probe_kpk(Square wksq, Square wpsq, Square bksq, Color stm) {
-
- int wp = square_file(wpsq) + 4 * (square_rank(wpsq) - 1);
- int index = int(stm) + 2 * bksq + 128 * wksq + 8192 * wp;
-
- assert(index >= 0 && index < 24576 * 8);
-
- return KPKBitbase[index / 8] & (1 << (index & 7));
- }
+ return probe_kpk_bitbase(wksq, wpsq, bksq, stm) ? SCALE_FACTOR_NONE : SCALE_FACTOR_ZERO;
}