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MJZ1977vondele
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Weak queen protection
Extra penalty if weak piece is only protected by a queen. STC: http://tests.stockfishchess.org/tests/view/5e53c6ab84a82b4acd4148fa LLR: 2.96 (-2.94,2.94) {-0.50,1.50} Total: 44630 W: 8615 L: 8359 D: 27656 Ptnml(0-2): 746, 5156, 10323, 5276, 814 LTC: http://tests.stockfishchess.org/tests/view/5e54e05d84a82b4acd414947 LLR: 2.94 (-2.94,2.94) {0.25,1.75} Total: 175480 W: 23085 L: 22409 D: 129986 Ptnml(0-2): 1264, 16494, 51678, 16910, 1394 closes #2564 Bench: 4923286
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src/evaluate.cpp

Lines changed: 5 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -114,11 +114,11 @@ namespace {
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// which piece type attacks which one. Attacks on lesser pieces which are
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// pawn-defended are not considered.
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constexpr Score ThreatByMinor[PIECE_TYPE_NB] = {
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S(0, 0), S(6, 32), S(59, 41), S(79, 56), S(90, 119), S(79, 161)
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S(0, 0), S(5, 32), S(57, 41), S(77, 56), S(88, 119), S(79, 161)
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};
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constexpr Score ThreatByRook[PIECE_TYPE_NB] = {
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S(0, 0), S(3, 44), S(38, 71), S(38, 61), S(0, 38), S(51, 38)
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S(0, 0), S(2, 44), S(36, 71), S(36, 61), S(0, 38), S(51, 38)
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};
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// PassedRank[Rank] contains a bonus according to the rank of a passed pawn
@@ -516,6 +516,9 @@ namespace {
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b = ~attackedBy[Them][ALL_PIECES]
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| (nonPawnEnemies & attackedBy2[Us]);
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score += Hanging * popcount(weak & b);
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// Additional bonus if weak piece is only protected by a queen
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score += make_score(14, 0) * popcount(weak & attackedBy[Them][QUEEN]);
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}
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// Bonus for restricting their piece moves

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