mirror of
https://github.com/sockspls/badfish
synced 2025-04-29 16:23:09 +00:00
Introduce evaluate_pawn_storm() to unify redundant code
No functional change. Signed-off-by: Marco Costalba <mcostalba@gmail.com>
This commit is contained in:
parent
0b49ec9822
commit
ea5af9b8c0
2 changed files with 52 additions and 59 deletions
102
src/pawns.cpp
102
src/pawns.cpp
|
@ -143,7 +143,7 @@ void PawnInfo::clear() {
|
|||
/// in a hash table, so we don't have to recompute everything when the same
|
||||
/// pawn structure occurs again.
|
||||
|
||||
PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) {
|
||||
PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) const {
|
||||
|
||||
assert(pos.is_ok());
|
||||
|
||||
|
@ -178,13 +178,13 @@ PawnInfo* PawnInfoTable::get_pawn_info(const Position& pos) {
|
|||
|
||||
template<Color Us>
|
||||
Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns,
|
||||
Bitboard theirPawns, PawnInfo* pi) {
|
||||
Bitboard theirPawns, PawnInfo* pi) const {
|
||||
Bitboard b;
|
||||
Square s, s2;
|
||||
Square s;
|
||||
File f;
|
||||
Rank r, r2;
|
||||
Rank r;
|
||||
int bonus;
|
||||
bool passed, isolated, doubled, opposed, chain, backward, candidate;
|
||||
int bonus, v;
|
||||
Score value = make_score(0, 0);
|
||||
const Square* ptr = pos.piece_list_begin(Us, PAWN);
|
||||
|
||||
|
@ -205,60 +205,15 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns,
|
|||
|
||||
assert(pos.piece_on(s) == piece_of_color_and_type(Us, PAWN));
|
||||
|
||||
// We calculate kingside and queenside pawn storm scores for
|
||||
// both colors. These are used when evaluating middle game
|
||||
// positions with opposite side castling.
|
||||
//
|
||||
// Each pawn is given a base score given by a piece square table
|
||||
// (KStormTable[] or QStormTable[]). Pawns which seem to have good
|
||||
// chances of creating an open file by exchanging itself against
|
||||
// an enemy pawn on an adjacent file gets an additional bonus.
|
||||
// Calculate kingside and queenside pawn storm scores for both colors to be
|
||||
// used when evaluating middle game positions with opposite side castling.
|
||||
bonus = (f >= FILE_F ? evaluate_pawn_storm<Us, KingSide>(s, r, f, theirPawns) : 0);
|
||||
pi->ksStormValue[Us] += KStormTable[relative_square(Us, s)] + bonus;
|
||||
|
||||
// Kingside pawn storms
|
||||
bonus = KStormTable[relative_square(Us, s)];
|
||||
if (f >= FILE_F)
|
||||
{
|
||||
b = outpost_mask(Us, s) & theirPawns & (FileFBB | FileGBB | FileHBB);
|
||||
while (b)
|
||||
{
|
||||
// Give a bonus according to the distance of the nearest enemy pawn
|
||||
s2 = pop_1st_bit(&b);
|
||||
r2 = square_rank(s2);
|
||||
v = StormLeverBonus[f] - 2 * rank_distance(r, r2);
|
||||
bonus = (f <= FILE_C ? evaluate_pawn_storm<Us, QueenSide>(s, r, f, theirPawns) : 0);
|
||||
pi->qsStormValue[Us] += QStormTable[relative_square(Us, s)] + bonus;
|
||||
|
||||
// If enemy pawn has no pawn beside itself is particularly vulnerable.
|
||||
// Big bonus, especially against a weakness on the rook file
|
||||
if (!(theirPawns & neighboring_files_bb(s2) & rank_bb(s2)))
|
||||
v *= (square_file(s2) == FILE_H ? 4 : 2);
|
||||
|
||||
bonus += v;
|
||||
}
|
||||
}
|
||||
pi->ksStormValue[Us] += bonus;
|
||||
|
||||
// Queenside pawn storms
|
||||
bonus = QStormTable[relative_square(Us, s)];
|
||||
if (f <= FILE_C)
|
||||
{
|
||||
b = outpost_mask(Us, s) & theirPawns & (FileABB | FileBBB | FileCBB);
|
||||
while (b)
|
||||
{
|
||||
// Give a bonus according to the distance of the nearest enemy pawn
|
||||
s2 = pop_1st_bit(&b);
|
||||
r2 = square_rank(s2);
|
||||
v = StormLeverBonus[f] - 4 * rank_distance(r, r2);
|
||||
|
||||
// If enemy pawn has no pawn beside itself is particularly vulnerable.
|
||||
// Big bonus, especially against a weakness on the rook file
|
||||
if (!(theirPawns & neighboring_files_bb(s2) & rank_bb(s2)))
|
||||
v *= (square_file(s2) == FILE_A ? 4 : 2);
|
||||
|
||||
bonus += v;
|
||||
}
|
||||
}
|
||||
pi->qsStormValue[Us] += bonus;
|
||||
|
||||
// Our rank and previous one. Used for chain detection.
|
||||
// Our rank plus previous one. Used for chain detection.
|
||||
b = rank_bb(r) | rank_bb(r + (Us == WHITE ? -1 : 1));
|
||||
|
||||
// Passed, isolated, doubled or member of a pawn
|
||||
|
@ -342,6 +297,39 @@ Score PawnInfoTable::evaluate_pawns(const Position& pos, Bitboard ourPawns,
|
|||
}
|
||||
|
||||
|
||||
/// PawnInfoTable::evaluate_pawn_storm() evaluates each pawn which seems
|
||||
/// to have good chances of creating an open file by exchanging itself
|
||||
/// against an enemy pawn on an adjacent file.
|
||||
|
||||
template<Color Us, PawnInfoTable::SideType Side>
|
||||
int PawnInfoTable::evaluate_pawn_storm(Square s, Rank r, File f, Bitboard theirPawns) const {
|
||||
|
||||
const Bitboard StormFilesBB = (Side == KingSide ? FileFBB | FileGBB | FileHBB
|
||||
: FileABB | FileBBB | FileCBB);
|
||||
const int K = (Side == KingSide ? 2 : 4);
|
||||
const File RookFile = (Side == KingSide ? FILE_H : FILE_A);
|
||||
|
||||
Bitboard b = outpost_mask(Us, s) & theirPawns & StormFilesBB;
|
||||
int bonus = 0;
|
||||
|
||||
while (b)
|
||||
{
|
||||
// Give a bonus according to the distance of the nearest enemy pawn
|
||||
Square s2 = pop_1st_bit(&b);
|
||||
Rank r2 = square_rank(s2);
|
||||
int v = StormLeverBonus[f] - K * rank_distance(r, r2);
|
||||
|
||||
// If enemy pawn has no pawn beside itself is particularly vulnerable.
|
||||
// Big bonus, especially against a weakness on the rook file
|
||||
if (!(theirPawns & neighboring_files_bb(s2) & rank_bb(s2)))
|
||||
v *= (square_file(s2) == RookFile ? 4 : 2);
|
||||
|
||||
bonus += v;
|
||||
}
|
||||
return bonus;
|
||||
}
|
||||
|
||||
|
||||
/// PawnInfo::updateShelter calculates and caches king shelter. It is called
|
||||
/// only when king square changes, about 20% of total get_king_shelter() calls.
|
||||
int PawnInfo::updateShelter(const Position& pos, Color c, Square ksq) {
|
||||
|
|
|
@ -78,14 +78,19 @@ private:
|
|||
|
||||
class PawnInfoTable {
|
||||
|
||||
enum SideType { KingSide, QueenSide };
|
||||
|
||||
public:
|
||||
PawnInfoTable(unsigned numOfEntries);
|
||||
~PawnInfoTable();
|
||||
PawnInfo* get_pawn_info(const Position& pos);
|
||||
PawnInfo* get_pawn_info(const Position& pos) const;
|
||||
|
||||
private:
|
||||
template<Color Us>
|
||||
Score evaluate_pawns(const Position& pos, Bitboard ourPawns, Bitboard theirPawns, PawnInfo* pi);
|
||||
Score evaluate_pawns(const Position& pos, Bitboard ourPawns, Bitboard theirPawns, PawnInfo* pi) const;
|
||||
|
||||
template<Color Us, SideType Side>
|
||||
int evaluate_pawn_storm(Square s, Rank r, File f, Bitboard theirPawns) const;
|
||||
|
||||
unsigned size;
|
||||
PawnInfo* entries;
|
||||
|
|
Loading…
Add table
Reference in a new issue