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Remove Weights

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Removed remaining redundant weights for pawn structure,
passed pawns, space and king safety by redistributing them
into individual evaluation terms.

STC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 15173 W: 2790 L: 2659 D: 9724

LTC:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 43433 W: 5936 L: 5846 D: 31651

Bench: 7156237

Resolves #586
This commit is contained in:
hxim
2016-02-07 20:58:20 +00:00
committed by Joona Kiiski
parent 4f6aa15228
commit 56dd58e6f9
2 changed files with 30 additions and 42 deletions
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50
src/evaluate.cpp
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@@ -107,18 +107,6 @@ namespace {
Pawns::Entry* pi;
};
// Evaluation weights, indexed by the corresponding evaluation term
enum { PawnStructure, PassedPawns, Space, KingSafety };
const struct Weight { int mg, eg; } Weights[] = {
{214, 203}, {193, 262}, {47, 0}, {330, 0} };
Score operator*(Score s, const Weight& w) {
return make_score(mg_value(s) * w.mg / 256, eg_value(s) * w.eg / 256);
}
#define V(v) Value(v)
#define S(mg, eg) make_score(mg, eg)
@@ -180,14 +168,14 @@ namespace {
// Passed[mg/eg][Rank] contains midgame and endgame bonuses for passed pawns.
// We don't use a Score because we process the two components independently.
const Value Passed[][RANK_NB] = {
{ V(0), V( 1), V(34), V(90), V(214), V(328) },
{ V(7), V(14), V(37), V(63), V(134), V(189) }
{ V(0), V( 1), V(26), V(68), V(161), V(247) },
{ V(7), V(14), V(38), V(64), V(137), V(193) }
};
// PassedFile[File] contains a bonus according to the file of a passed pawn
const Score PassedFile[FILE_NB] = {
S( 12, 10), S( 3, 10), S( 1, -8), S(-27,-12),
S(-27,-12), S( 1, -8), S( 3, 10), S( 12, 10)
S( 9, 10), S( 2, 10), S( 1, -8), S(-20,-12),
S(-20,-12), S( 1, -8), S( 2, 10), S( 9, 10)
};
// Assorted bonuses and penalties used by evaluation
@@ -627,10 +615,10 @@ namespace {
else if (defendedSquares & blockSq)
k += 4;
mbonus += k * rr, ebonus += k * rr;
mbonus += k * rr * 3 / 4, ebonus += k * rr;
}
else if (pos.pieces(Us) & blockSq)
mbonus += rr * 3 + r * 2 + 3, ebonus += rr + r * 2;
mbonus += (rr * 3 + r * 2 + 3) * 3 / 4, ebonus += rr + r * 2;
} // rr != 0
if (pos.count<PAWN>(Us) < pos.count<PAWN>(Them))
@@ -640,10 +628,10 @@ namespace {
}
if (DoTrace)
Trace::add(PASSED, Us, score * Weights[PassedPawns]);
Trace::add(PASSED, Us, score);
// Add the scores to the middlegame and endgame eval
return score * Weights[PassedPawns];
return score;
}
@@ -682,7 +670,7 @@ namespace {
int weight = pos.count<KNIGHT>(Us) + pos.count<BISHOP>(Us)
+ pos.count<KNIGHT>(Them) + pos.count<BISHOP>(Them);
return make_score(bonus * weight * weight, 0);
return make_score(bonus * weight * weight * 2 / 11, 0);
}
@@ -771,7 +759,7 @@ Value Eval::evaluate(const Position& pos) {
// Probe the pawn hash table
ei.pi = Pawns::probe(pos);
score += ei.pi->pawns_score() * Weights[PawnStructure];
score += ei.pi->pawns_score();
// Initialize attack and king safety bitboards
ei.attackedBy[WHITE][ALL_PIECES] = ei.attackedBy[BLACK][ALL_PIECES] = 0;
@@ -821,8 +809,8 @@ Value Eval::evaluate(const Position& pos) {
// Evaluate space for both sides, only during opening
if (pos.non_pawn_material(WHITE) + pos.non_pawn_material(BLACK) >= 12222)
score += ( evaluate_space<WHITE>(pos, ei)
- evaluate_space<BLACK>(pos, ei)) * Weights[Space];
score += evaluate_space<WHITE>(pos, ei)
- evaluate_space<BLACK>(pos, ei);
// Evaluate position potential for the winning side
score += evaluate_initiative(pos, ei.pi->pawn_asymmetry(), eg_value(score));
@@ -841,10 +829,10 @@ Value Eval::evaluate(const Position& pos) {
{
Trace::add(MATERIAL, pos.psq_score());
Trace::add(IMBALANCE, ei.me->imbalance());
Trace::add(PAWN, ei.pi->pawns_score() * Weights[PawnStructure]);
Trace::add(PAWN, ei.pi->pawns_score());
Trace::add(MOBILITY, mobility[WHITE], mobility[BLACK]);
Trace::add(SPACE, evaluate_space<WHITE>(pos, ei) * Weights[Space]
, evaluate_space<BLACK>(pos, ei) * Weights[Space]);
Trace::add(SPACE, evaluate_space<WHITE>(pos, ei)
, evaluate_space<BLACK>(pos, ei));
Trace::add(TOTAL, score);
}
@@ -897,13 +885,13 @@ std::string Eval::trace(const Position& pos) {
void Eval::init() {
const int MaxSlope = 8700;
const int Peak = 1280000;
const int MaxSlope = 322;
const int Peak = 47410;
int t = 0;
for (int i = 0; i < 400; ++i)
{
t = std::min(Peak, std::min(i * i * 27, t + MaxSlope));
KingDanger[i] = make_score(t / 1000, 0) * Weights[KingSafety];
t = std::min(Peak, std::min(i * i - 16, t + MaxSlope));
KingDanger[i] = make_score(t * 268 / 7700, 0);
}
}