stellar

commit 5dcc9ef4920e4b1ca8a653d066c9f4ace83f315c
parent 8bfcd0ddad32537cc686a87dc8200626e7be81d5
Author: Dimitrije Dobrota <mail@dimitrijedobrota.com>
Date:   Wed, 13 Mar 2024 23:10:19 +0000

Improve Zobrist lookup tables

Diffstat:
M
CMakeLists.txt
 | 
2
+-
M
src/board/board.cpp
 | 
10
+++++++---
M
src/board/board.hpp
 | 
6
++----
M
src/board/zobrist.hpp
 | 
14
++++++--------

4 files changed, 16 insertions(+), 16 deletions(-)
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -3,7 +3,7 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
 project(
     Stellar
-	VERSION 1.3.5
+	VERSION 1.3.6
     DESCRIPTION "Chess engine written in C++"
 	HOMEPAGE_URL https://git.dimitrijedobrota.com/stellar.git
     LANGUAGES CXX
diff --git a/src/board/board.cpp b/src/board/board.cpp
@@ -8,10 +8,14 @@
 #include "utils_ui.hpp"
 #include "zobrist.hpp"
 
+namespace zobrist {
+
 /* Init arrays for Zobris hashing */
-std::array<std::array<U64, 64>, 12> zobrist::keys_piece = {{{0}}};
-std::array<U64, 64> zobrist::keys_enpassant = {{0}};
-std::array<U64, 16> zobrist::keys_castle = {{0}};
+U64 keys_piece[2][12][64] = {0};
+U64 keys_enpassant[64] = {0};
+U64 keys_castle[16] = {0};
+
+} // namespace zobrist
 
 /* Getters */
 
diff --git a/src/board/board.hpp b/src/board/board.hpp
@@ -197,13 +197,11 @@ U64 zobrist::hash(const Board &board) {
     uint8_t square = 0;
 
     for (Type type = PAWN; type <= KING; ++type) {
-        int piece_white_index = piece::get_index(type, WHITE);
         U64 bitboard_white = board.get_bitboard_piece(type, WHITE);
-        bitboard_for_each_bit(square, bitboard_white) { key_final ^= keys_piece[piece_white_index][square]; }
+        bitboard_for_each_bit(square, bitboard_white) { key_final ^= keys_piece[WHITE][type][square]; }
 
-        int piece_black_index = piece::get_index(type, BLACK);
         U64 bitboard_black = board.get_bitboard_piece(type, BLACK);
-        bitboard_for_each_bit(square, bitboard_black) { key_final ^= keys_piece[piece_black_index][square]; }
+        bitboard_for_each_bit(square, bitboard_black) { key_final ^= keys_piece[BLACK][type][square]; }
     }
 
     key_final ^= keys_castle[board.get_castle()];
diff --git a/src/board/zobrist.hpp b/src/board/zobrist.hpp
@@ -11,20 +11,18 @@
 class Board;
 namespace zobrist {
 
-extern std::array<std::array<U64, 64>, 12> keys_piece;
-extern std::array<U64, 64> keys_enpassant;
-extern std::array<U64, 16> keys_castle;
+extern U64 keys_piece[2][12][64];
+extern U64 keys_enpassant[64];
+extern U64 keys_castle[16];
 
 const U64 keys_side = Random(C32(1699391443))();
 
 inline void init() {
     Random gen1(C64(1804289383));
     for (Type type = PAWN; type <= KING; ++type) {
-        int piece_index_white = piece::get(type, Color::WHITE).index;
-        int piece_index_black = piece::get(type, Color::BLACK).index;
         for (int square = 0; square < 64; square++) {
-            keys_piece[piece_index_white][square] = gen1();
-            keys_piece[piece_index_black][square] = gen1();
+            keys_piece[WHITE][type][square] = gen1();
+            keys_piece[BLACK][type][square] = gen1();
         }
     }
 
@@ -44,7 +42,7 @@ inline constexpr U64 key_side() { return keys_side; }
 inline constexpr U64 key_castle(int exp) { return keys_castle[exp]; }
 inline constexpr U64 key_enpassant(Square square) { return keys_enpassant[square]; }
 inline constexpr U64 key_piece(Type type, Color color, Square square) {
-    return keys_piece[piece::get_index(type, color)][square];
+    return keys_piece[color][type][square];
 }
 
 }; // namespace zobrist