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Change outposts to single value official-stockfish#1946

This is a functional simplification of the Outposts array
moving it to a single value. This is a duplicate PR because
I couldn't figure out how to fix the original one.

The idea is from @31m059 with formatting recommendations by @snicolet.

See official-stockfish#1940 for additional information.

STC
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 23933 W: 5279 L: 5162 D: 13492
http://tests.stockfishchess.org/tests/view/5c3575800ebc596a450c5ecb

LTC
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 41718 W: 6919 L: 6831 D: 27968
http://tests.stockfishchess.org/tests/view/5c358c440ebc596a450c6117

bench 3783543
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protonspring authored and mcostalba committed Jan 13, 2019
1 parent 05f7d59 commit 3c92f849ab940fd9ac70e838e6d941827fc69cb6
Showing with 5 additions and 10 deletions.
  1. +5 −10 src/evaluate.cpp
@@ -117,14 +117,6 @@ namespace {
S(106,184), S(109,191), S(113,206), S(116,212) }
};

// Outpost[knight/bishop][supported by pawn] contains bonuses for minor
// pieces if they occupy or can reach an outpost square, bigger if that
// square is supported by a pawn.
constexpr Score Outpost[][2] = {
{ S(22, 6), S(36,12) }, // Knight
{ S( 9, 2), S(15, 5) } // Bishop
};

// RookOnFile[semiopen/open] contains bonuses for each rook when there is
// no (friendly) pawn on the rook file.
constexpr Score RookOnFile[] = { S(18, 7), S(44, 20) };
@@ -171,6 +163,7 @@ namespace {
constexpr Score TrappedRook = S( 47, 4);
constexpr Score WeakQueen = S( 49, 15);
constexpr Score WeakUnopposedPawn = S( 12, 23);
constexpr Score Outpost = S( 9, 3);

#undef S

@@ -324,10 +317,12 @@ namespace {
// Bonus if piece is on an outpost square or can reach one
bb = OutpostRanks & ~pe->pawn_attacks_span(Them);
if (bb & s)
score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & s)] * 2;
score += Outpost * (Pt == KNIGHT ? 4 : 2)
* (1 + bool(attackedBy[Us][PAWN] & s));

else if (bb &= b & ~pos.pieces(Us))
score += Outpost[Pt == BISHOP][bool(attackedBy[Us][PAWN] & bb)];
score += Outpost * (Pt == KNIGHT ? 2 : 1)
* (1 + bool(attackedBy[Us][PAWN] & bb));

// Knight and Bishop bonus for being right behind a pawn
if (shift<Down>(pos.pieces(PAWN)) & s)

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