X-Git-Url: https://git.sesse.net/?p=stockfish;a=blobdiff_plain;f=src%2Fmaterial.cpp;h=3a05f3faf6b374aee5bd72ea221dd12fce3281b4;hp=ebf5adff854abc4bb6770c6547795e72c7d791c7;hb=dc243a3c880d0a736fb93848cf56e3221e07f8a3;hpb=be509525336b65419e708678abe4e16efb5f6f4d
diff --git a/src/material.cpp b/src/material.cpp
index ebf5adff..3a05f3fa 100644
--- a/src/material.cpp
+++ b/src/material.cpp
@@ -2,6 +2,7 @@
Stockfish, a UCI chess playing engine derived from Glaurung 2.1
Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
+ Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
Stockfish is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
@@ -17,7 +18,6 @@
along with this program. If not, see .
*/
-#include // For std::min
#include
#include // For std::memset
@@ -30,29 +30,26 @@ namespace {
// Polynomial material imbalance parameters
- // pair pawn knight bishop rook queen
- const int Linear[6] = { 1852, -162, -1122, -183, 249, -154 };
-
- const int QuadraticOurs[][PIECE_TYPE_NB] = {
+ constexpr int QuadraticOurs[][PIECE_TYPE_NB] = {
// OUR PIECES
// pair pawn knight bishop rook queen
- { 0 }, // Bishop pair
- { 39, 2 }, // Pawn
- { 35, 271, -4 }, // Knight OUR PIECES
- { 0, 105, 4, 0 }, // Bishop
- { -27, -2, 46, 100, -141 }, // Rook
- {-177, 25, 129, 142, -137, 0 } // Queen
+ {1438 }, // Bishop pair
+ { 40, 38 }, // Pawn
+ { 32, 255, -62 }, // Knight OUR PIECES
+ { 0, 104, 4, 0 }, // Bishop
+ { -26, -2, 47, 105, -208 }, // Rook
+ {-189, 24, 117, 133, -134, -6 } // Queen
};
- const int QuadraticTheirs[][PIECE_TYPE_NB] = {
+ constexpr int QuadraticTheirs[][PIECE_TYPE_NB] = {
// THEIR PIECES
// pair pawn knight bishop rook queen
{ 0 }, // Bishop pair
- { 37, 0 }, // Pawn
- { 10, 62, 0 }, // Knight OUR PIECES
- { 57, 64, 39, 0 }, // Bishop
- { 50, 40, 23, -22, 0 }, // Rook
- { 98, 105, -39, 141, 274, 0 } // Queen
+ { 36, 0 }, // Pawn
+ { 9, 63, 0 }, // Knight OUR PIECES
+ { 59, 65, 42, 0 }, // Bishop
+ { 46, 39, 24, -24, 0 }, // Rook
+ { 97, 100, -42, 137, 268, 0 } // Queen
};
// Endgame evaluation and scaling functions are accessed directly and not through
@@ -70,16 +67,14 @@ namespace {
&& pos.non_pawn_material(us) >= RookValueMg;
}
- bool is_KBPsKs(const Position& pos, Color us) {
+ bool is_KBPsK(const Position& pos, Color us) {
return pos.non_pawn_material(us) == BishopValueMg
- && pos.count(us) == 1
&& pos.count(us) >= 1;
}
bool is_KQKRPs(const Position& pos, Color us) {
return !pos.count(us)
&& pos.non_pawn_material(us) == QueenValueMg
- && pos.count(us) == 1
&& pos.count(~us) == 1
&& pos.count(~us) >= 1;
}
@@ -89,17 +84,17 @@ namespace {
template
int imbalance(const int pieceCount[][PIECE_TYPE_NB]) {
- const Color Them = (Us == WHITE ? BLACK : WHITE);
+ constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
int bonus = 0;
- // Second-degree polynomial material imbalance by Tord Romstad
+ // Second-degree polynomial material imbalance, by Tord Romstad
for (int pt1 = NO_PIECE_TYPE; pt1 <= QUEEN; ++pt1)
{
if (!pieceCount[Us][pt1])
continue;
- int v = Linear[pt1];
+ int v = 0;
for (int pt2 = NO_PIECE_TYPE; pt2 <= pt1; ++pt2)
v += QuadraticOurs[pt1][pt2] * pieceCount[Us][pt2]
@@ -131,12 +126,18 @@ Entry* probe(const Position& pos) {
std::memset(e, 0, sizeof(Entry));
e->key = key;
e->factor[WHITE] = e->factor[BLACK] = (uint8_t)SCALE_FACTOR_NORMAL;
- e->gamePhase = pos.game_phase();
+
+ Value npm_w = pos.non_pawn_material(WHITE);
+ Value npm_b = pos.non_pawn_material(BLACK);
+ Value npm = clamp(npm_w + npm_b, EndgameLimit, MidgameLimit);
+
+ // Map total non-pawn material into [PHASE_ENDGAME, PHASE_MIDGAME]
+ e->gamePhase = Phase(((npm - EndgameLimit) * PHASE_MIDGAME) / (MidgameLimit - EndgameLimit));
// Let's look if we have a specialized evaluation function for this particular
// material configuration. Firstly we look for a fixed configuration one, then
// for a generic one if the previous search failed.
- if ((e->evaluationFunction = pos.this_thread()->endgames.probe(key)) != nullptr)
+ if ((e->evaluationFunction = Endgames::probe(key)) != nullptr)
return e;
for (Color c = WHITE; c <= BLACK; ++c)
@@ -148,11 +149,11 @@ Entry* probe(const Position& pos) {
// OK, we didn't find any special evaluation function for the current material
// configuration. Is there a suitable specialized scaling function?
- EndgameBase* sf;
+ const auto* sf = Endgames::probe(key);
- if ((sf = pos.this_thread()->endgames.probe(key)) != nullptr)
+ if (sf)
{
- e->scalingFunction[sf->strong_side()] = sf; // Only strong color assigned
+ e->scalingFunction[sf->strongSide] = sf; // Only strong color assigned
return e;
}
@@ -161,16 +162,13 @@ Entry* probe(const Position& pos) {
// case we don't return after setting the function.
for (Color c = WHITE; c <= BLACK; ++c)
{
- if (is_KBPsKs(pos, c))
+ if (is_KBPsK(pos, c))
e->scalingFunction[c] = &ScaleKBPsK[c];
else if (is_KQKRPs(pos, c))
e->scalingFunction[c] = &ScaleKQKRPs[c];
}
- Value npm_w = pos.non_pawn_material(WHITE);
- Value npm_b = pos.non_pawn_material(BLACK);
-
if (npm_w + npm_b == VALUE_ZERO && pos.pieces(PAWN)) // Only pawns on the board
{
if (!pos.count(BLACK))
@@ -199,28 +197,22 @@ Entry* probe(const Position& pos) {
// drawish scale factor for cases such as KRKBP and KmmKm (except for KBBKN).
if (!pos.count(WHITE) && npm_w - npm_b <= BishopValueMg)
e->factor[WHITE] = uint8_t(npm_w < RookValueMg ? SCALE_FACTOR_DRAW :
- npm_b <= BishopValueMg ? 4 : 12);
+ npm_b <= BishopValueMg ? 4 : 14);
if (!pos.count(BLACK) && npm_b - npm_w <= BishopValueMg)
e->factor[BLACK] = uint8_t(npm_b < RookValueMg ? SCALE_FACTOR_DRAW :
- npm_w <= BishopValueMg ? 4 : 12);
-
- if (pos.count(WHITE) == 1 && npm_w - npm_b <= BishopValueMg)
- e->factor[WHITE] = (uint8_t) SCALE_FACTOR_ONEPAWN;
-
- if (pos.count(BLACK) == 1 && npm_b - npm_w <= BishopValueMg)
- e->factor[BLACK] = (uint8_t) SCALE_FACTOR_ONEPAWN;
+ npm_w <= BishopValueMg ? 4 : 14);
// Evaluate the material imbalance. We use PIECE_TYPE_NONE as a place holder
// for the bishop pair "extended piece", which allows us to be more flexible
// in defining bishop pair bonuses.
- const int PieceCount[COLOR_NB][PIECE_TYPE_NB] = {
+ const int pieceCount[COLOR_NB][PIECE_TYPE_NB] = {
{ pos.count(WHITE) > 1, pos.count(WHITE), pos.count(WHITE),
pos.count(WHITE) , pos.count(WHITE), pos.count(WHITE) },
{ pos.count(BLACK) > 1, pos.count(BLACK), pos.count(BLACK),
pos.count(BLACK) , pos.count(BLACK), pos.count(BLACK) } };
- e->value = int16_t((imbalance(PieceCount) - imbalance(PieceCount)) / 16);
+ e->value = int16_t((imbalance(pieceCount) - imbalance(pieceCount)) / 16);
return e;
}