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.
-
+
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 <http://www.gnu.org/licenses/>.
*/
Value(32), Value(32), Value(32), Value(28)
};
- // Pawn chain membership bonus by file, middle game.
+ // Pawn chain membership bonus by file, middle game.
const Value ChainMidgameBonus[8] = {
Value(14), Value(16), Value(17), Value(18),
Value(18), Value(17), Value(16), Value(14)
};
- // Pawn chain membership bonus by file, endgame.
+ // Pawn chain membership bonus by file, endgame.
const Value ChainEndgameBonus[8] = {
Value(16), Value(16), Value(16), Value(16),
Value(16), Value(16), Value(16), Value(16)
Value(80), Value(180), Value(0), Value( 0)
};
- // Evaluate pawn storms?
- const bool EvaluatePawnStorms = true;
-
// Pawn storm tables for positions with opposite castling:
const int QStormTable[64] = {
0, 0, 0, 0, 0, 0, 0, 0,
31, 40, 40, 31, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0
};
-
+
const int KStormTable[64] = {
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0,-4,-13,-22,-27,-27,
/// PawnInfoTable::get_pawn_info() takes a position object as input, computes
-/// a PawnInfo object, and returns a pointer to it. The result is also
+/// a PawnInfo object, and returns a pointer to it. The result is also
/// stored in a hash table, so we don't have to recompute everything when
/// the same pawn structure occurs again.
int index = int(key & (size - 1));
PawnInfo *pi = entries + index;
- // If pi->key matches the position's pawn hash key, it means that we
+ // If pi->key matches the position's pawn hash key, it means that we
// have analysed this pawn structure before, and we can simply return the
// information we found the last time instead of recomputing it
if (pi->key == key)
Bitboard pawns = ourPawns;
// Initialize pawn storm scores by giving bonuses for open files
- if (EvaluatePawnStorms)
- for(File f = FILE_A; f <= FILE_H; f++)
- if(pos.file_is_half_open(us, f))
- {
- pi->ksStormValue[us] += KStormOpenFileBonus[f];
- pi->qsStormValue[us] += QStormOpenFileBonus[f];
- }
+ for (File f = FILE_A; f <= FILE_H; f++)
+ if (pos.file_is_half_open(us, f))
+ {
+ pi->ksStormValue[us] += KStormOpenFileBonus[f];
+ pi->qsStormValue[us] += QStormOpenFileBonus[f];
+ }
// Loop through all pawns of the current color and score each pawn
while (pawns)
isolated = pos.pawn_is_isolated(us, s);
doubled = pos.pawn_is_doubled(us, s);
- if (EvaluatePawnStorms)
- {
- // 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[]). This score is increased if
- // there are enemy pawns on adjacent files in front of the pawn.
- // This is because we want to be able to open files against the
- // enemy king, and to avoid blocking the pawn structure (e.g. white
- // pawns on h6, g5, black pawns on h7, g6, f7).
-
- // Kingside and queenside pawn storms
- int KBonus = KStormTable[relative_square(us, s)];
- int QBonus = QStormTable[relative_square(us, s)];
- bool outPost = (KBonus > 0 && (outpost_mask(us, s) & theirPawns));
- bool passed = (QBonus > 0 && (passed_pawn_mask(us, s) & theirPawns));
-
- switch (f) {
-
- case FILE_A:
- QBonus += passed * QBonus / 2;
- break;
-
- case FILE_B:
- QBonus += passed * (QBonus / 2 + QBonus / 4);
- break;
-
- case FILE_C:
- QBonus += passed * QBonus / 2;
- break;
-
- case FILE_F:
- KBonus += outPost * KBonus / 4;
- break;
-
- case FILE_G:
- KBonus += outPost * (KBonus / 2 + KBonus / 4);
- break;
-
- case FILE_H:
- KBonus += outPost * KBonus / 2;
- break;
-
- default:
- break;
- }
- pi->ksStormValue[us] += KBonus;
- pi->qsStormValue[us] += QBonus;
+ // 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[]). This score is increased if
+ // there are enemy pawns on adjacent files in front of the pawn.
+ // This is because we want to be able to open files against the
+ // enemy king, and to avoid blocking the pawn structure (e.g. white
+ // pawns on h6, g5, black pawns on h7, g6, f7).
+
+ // Kingside and queenside pawn storms
+ int KBonus = KStormTable[relative_square(us, s)];
+ int QBonus = QStormTable[relative_square(us, s)];
+ bool outPostFlag = (KBonus > 0 && (outpost_mask(us, s) & theirPawns));
+ bool passedFlag = (QBonus > 0 && (passed_pawn_mask(us, s) & theirPawns));
+
+ switch (f) {
+
+ case FILE_A:
+ QBonus += passedFlag * QBonus / 2;
+ break;
+
+ case FILE_B:
+ QBonus += passedFlag * (QBonus / 2 + QBonus / 4);
+ break;
+
+ case FILE_C:
+ QBonus += passedFlag * QBonus / 2;
+ break;
+
+ case FILE_F:
+ KBonus += outPostFlag * KBonus / 4;
+ break;
+
+ case FILE_G:
+ KBonus += outPostFlag * (KBonus / 2 + KBonus / 4);
+ break;
+
+ case FILE_H:
+ KBonus += outPostFlag * KBonus / 2;
+ break;
+
+ default:
+ break;
}
+ pi->ksStormValue[us] += KBonus;
+ pi->qsStormValue[us] += QBonus;
// Member of a pawn chain (but not the backward one)? We could speed up
// the test a little by introducing an array of masks indexed by color
mgValue[us] += mv;
egValue[us] += ev;
-
+
// If the pawn is passed, set the square of the pawn in the passedPawns
// bitboard
if (passed)
projects / stockfish / blobdiff