X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fendgame.cpp;h=a44d3a1c5e66f3c10a1f40853c41794f80dc81dc;hb=673841301b0cc6ed78c4db3e6ec2a0b9a010c8cb;hp=7a47a3e170f9d908ba808b79c0ed25b911e82763;hpb=f56af8e84db25c0d26fe762fbe171ec5518177bb;p=stockfish
diff --git a/src/endgame.cpp b/src/endgame.cpp
index 7a47a3e1..a44d3a1c 100644
--- a/src/endgame.cpp
+++ b/src/endgame.cpp
@@ -1,867 +1,747 @@
/*
- Glaurung, a UCI chess playing engine.
- Copyright (C) 2004-2008 Tord Romstad
+ Stockfish, a UCI chess playing engine derived from Glaurung 2.1
+ Copyright (C) 2004-2021 The Stockfish developers (see AUTHORS file)
- Glaurung is free software: you can redistribute it and/or modify
+ Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
-
- Glaurung is distributed in the hope that it will be useful,
+
+ Stockfish is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
-
+
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
-
-////
-//// Includes
-////
-
#include
-#include "bitbase.h"
+#include "bitboard.h"
#include "endgame.h"
+#include "movegen.h"
+namespace Stockfish {
-////
-//// Constants and variables
-////
-
-/// Evaluation functions
-
-// Generic "mate lone king" eval:
-KXKEvaluationFunction EvaluateKXK = KXKEvaluationFunction(WHITE);
-KXKEvaluationFunction EvaluateKKX = KXKEvaluationFunction(BLACK);
-
-// KBN vs K:
-KBNKEvaluationFunction EvaluateKBNK = KBNKEvaluationFunction(WHITE);
-KBNKEvaluationFunction EvaluateKKBN = KBNKEvaluationFunction(BLACK);
-
-// KP vs K:
-KPKEvaluationFunction EvaluateKPK = KPKEvaluationFunction(WHITE);
-KPKEvaluationFunction EvaluateKKP = KPKEvaluationFunction(BLACK);
-
-// KR vs KP:
-KRKPEvaluationFunction EvaluateKRKP = KRKPEvaluationFunction(WHITE);
-KRKPEvaluationFunction EvaluateKPKR = KRKPEvaluationFunction(BLACK);
+namespace {
-// KR vs KB:
-KRKBEvaluationFunction EvaluateKRKB = KRKBEvaluationFunction(WHITE);
-KRKBEvaluationFunction EvaluateKBKR = KRKBEvaluationFunction(BLACK);
+ // Used to drive the king towards the edge of the board
+ // in KX vs K and KQ vs KR endgames.
+ // Values range from 27 (center squares) to 90 (in the corners)
+ inline int push_to_edge(Square s) {
+ int rd = edge_distance(rank_of(s)), fd = edge_distance(file_of(s));
+ return 90 - (7 * fd * fd / 2 + 7 * rd * rd / 2);
+ }
-// KR vs KN:
-KRKNEvaluationFunction EvaluateKRKN = KRKNEvaluationFunction(WHITE);
-KRKNEvaluationFunction EvaluateKNKR = KRKNEvaluationFunction(BLACK);
+ // Used to drive the king towards A1H8 corners in KBN vs K endgames.
+ // Values range from 0 on A8H1 diagonal to 7 in A1H8 corners
+ inline int push_to_corner(Square s) {
+ return abs(7 - rank_of(s) - file_of(s));
+ }
-// KQ vs KR:
-KQKREvaluationFunction EvaluateKQKR = KQKREvaluationFunction(WHITE);
-KQKREvaluationFunction EvaluateKRKQ = KQKREvaluationFunction(BLACK);
+ // Drive a piece close to or away from another piece
+ inline int push_close(Square s1, Square s2) { return 140 - 20 * distance(s1, s2); }
+ inline int push_away(Square s1, Square s2) { return 120 - push_close(s1, s2); }
+#ifndef NDEBUG
+ bool verify_material(const Position& pos, Color c, Value npm, int pawnsCnt) {
+ return pos.non_pawn_material(c) == npm && pos.count(c) == pawnsCnt;
+ }
+#endif
-/// Scaling functions
+ // Map the square as if strongSide is white and strongSide's only pawn
+ // is on the left half of the board.
+ Square normalize(const Position& pos, Color strongSide, Square sq) {
-// KBP vs K:
-KBPKScalingFunction ScaleKBPK = KBPKScalingFunction(WHITE);
-KBPKScalingFunction ScaleKKBP = KBPKScalingFunction(BLACK);
+ assert(pos.count(strongSide) == 1);
-// KQ vs KRP:
-KQKRPScalingFunction ScaleKQKRP = KQKRPScalingFunction(WHITE);
-KQKRPScalingFunction ScaleKRPKQ = KQKRPScalingFunction(BLACK);
+ if (file_of(pos.square(strongSide)) >= FILE_E)
+ sq = flip_file(sq);
-// KRP vs KR:
-KRPKRScalingFunction ScaleKRPKR = KRPKRScalingFunction(WHITE);
-KRPKRScalingFunction ScaleKRKRP = KRPKRScalingFunction(BLACK);
+ return strongSide == WHITE ? sq : flip_rank(sq);
+ }
-// KRPP vs KRP:
-KRPPKRPScalingFunction ScaleKRPPKRP = KRPPKRPScalingFunction(WHITE);
-KRPPKRPScalingFunction ScaleKRPKRPP = KRPPKRPScalingFunction(BLACK);
+} // namespace
-// King and pawns vs king:
-KPsKScalingFunction ScaleKPsK = KPsKScalingFunction(WHITE);
-KPsKScalingFunction ScaleKKPs = KPsKScalingFunction(BLACK);
-// KBP vs KB:
-KBPKBScalingFunction ScaleKBPKB = KBPKBScalingFunction(WHITE);
-KBPKBScalingFunction ScaleKBKBP = KBPKBScalingFunction(BLACK);
+namespace Endgames {
-// KBP vs KN:
-KBPKNScalingFunction ScaleKBPKN = KBPKNScalingFunction(WHITE);
-KBPKNScalingFunction ScaleKNKBP = KBPKNScalingFunction(BLACK);
+ std::pair