2008-08-31 23:59:13 -06:00
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/*
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2008-10-19 10:56:28 -06:00
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Stockfish, a UCI chess playing engine derived from Glaurung 2.1
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Copyright (C) 2004-2008 Tord Romstad (Glaurung author)
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2016-01-02 02:43:25 -07:00
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Copyright (C) 2008-2015 Marco Costalba, Joona Kiiski, Tord Romstad
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2018-11-19 03:18:21 -07:00
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Copyright (C) 2015-2019 Marco Costalba, Joona Kiiski, Gary Linscott, Tord Romstad
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2008-08-31 23:59:13 -06:00
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2008-10-19 10:56:28 -06:00
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Stockfish is free software: you can redistribute it and/or modify
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2008-08-31 23:59:13 -06:00
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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2009-01-07 06:26:58 -07:00
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2008-10-19 10:56:28 -06:00
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Stockfish is distributed in the hope that it will be useful,
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2008-08-31 23:59:13 -06:00
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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2009-01-07 06:26:58 -07:00
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2008-08-31 23:59:13 -06:00
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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2019-03-31 04:02:19 -06:00
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#include <algorithm>
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2008-08-31 23:59:13 -06:00
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#include <cassert>
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2011-04-09 12:50:56 -06:00
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#include "bitboard.h"
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2008-08-31 23:59:13 -06:00
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#include "pawns.h"
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2009-03-18 08:36:03 -06:00
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#include "position.h"
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2014-12-30 02:31:50 -07:00
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#include "thread.h"
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2008-08-31 23:59:13 -06:00
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namespace {
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2012-03-28 23:04:44 -06:00
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#define V Value
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2009-11-13 09:23:21 -07:00
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#define S(mg, eg) make_score(mg, eg)
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2008-08-31 23:59:13 -06:00
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2018-06-02 09:41:37 -06:00
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// Pawn penalties
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2019-06-09 07:07:36 -06:00
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constexpr Score Backward = S( 9, 24);
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2019-08-24 00:16:20 -06:00
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constexpr Score BlockedStorm = S(82, 82);
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2019-06-09 07:07:36 -06:00
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constexpr Score Doubled = S(11, 56);
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constexpr Score Isolated = S( 5, 15);
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2019-07-25 01:02:26 -06:00
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constexpr Score WeakLever = S( 0, 56);
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Exclude passed pawns from Attacked2Unsupported
We recently added a bonus for double pawn attacks on unsupported enemy pawns,
on June 27. However, it is possible that the unsupported pawn may become a passer
by simply pushing forward out of the double attack. By rewarding double attacks,
we may inadvertently reward the creation of enemy passers, by encouraging both of
our would-be stoppers to attack the enemy pawn even if there is no opposing
friendly pawn on the same file.
Here, we revise this term to exclude passed pawns. In order to simplify the code
with this change included, we non-functionally rewrite Attacked2Unsupported to
be a penalty for enemy attacks on friendly pawns, rather than a bonus for our
attacks on enemy pawns. This allows us to exclude passed pawns with a simple
& ~e->passedPawns[Us], while passedPawns[Them] is not yet defined in this part
of the code.
This dramatically reduces the proportion of positions in which Attacked2Unsupported
is applied, to about a third of the original. To compensate, maintaining the same
average effect across our bench positions, we nearly triple Attacked2Unsupported
from S(0, 20) to S(0, 56). Although this pawn formation is rare, it is worth more
than half a pawn in the endgame!
STC: (stopped automatically by fishtest after 250,000 games)
LLR: -0.87 (-2.94,2.94) [0.50,4.50]
Total: 250000 W: 56585 L: 55383 D: 138032
http://tests.stockfishchess.org/tests/view/5d25795e0ebc5925cf0cfb51
LTC:
LLR: 2.96 (-2.94,2.94) [0.00,3.50]
Total: 81038 W: 13965 L: 13558 D: 53515
http://tests.stockfishchess.org/tests/view/5d25f3920ebc5925cf0d10dd
Closes https://github.com/official-stockfish/Stockfish/pull/2233
Bench: 3765158
2019-07-11 07:14:57 -06:00
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constexpr Score WeakUnopposed = S(13, 27);
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2016-01-16 14:34:29 -07:00
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2019-03-25 13:04:14 -06:00
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// Connected pawn bonus
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2019-04-23 12:26:58 -06:00
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constexpr int Connected[RANK_NB] = { 0, 7, 8, 12, 29, 48, 86 };
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2016-01-16 14:34:29 -07:00
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2018-04-23 01:48:53 -06:00
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// Strength of pawn shelter for our king by [distance from edge][rank].
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// RANK_1 = 0 is used for files where we have no pawn, or pawn is behind our king.
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2018-07-15 06:30:59 -06:00
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constexpr Value ShelterStrength[int(FILE_NB) / 2][RANK_NB] = {
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2018-08-17 02:19:32 -06:00
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{ V( -6), V( 81), V( 93), V( 58), V( 39), V( 18), V( 25) },
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{ V(-43), V( 61), V( 35), V(-49), V(-29), V(-11), V( -63) },
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{ V(-10), V( 75), V( 23), V( -2), V( 32), V( 3), V( -45) },
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{ V(-39), V(-13), V(-29), V(-52), V(-48), V(-67), V(-166) }
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2016-09-23 11:28:34 -06:00
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};
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2012-03-26 05:52:10 -06:00
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2018-05-24 10:46:38 -06:00
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// Danger of enemy pawns moving toward our king by [distance from edge][rank].
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2018-06-02 09:41:37 -06:00
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// RANK_1 = 0 is used for files where the enemy has no pawn, or their pawn
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2019-08-14 14:15:41 -06:00
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// is behind our king. Note that UnblockedStorm[0][1-2] accommodate opponent pawn
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// on edge, likely blocked by our king.
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2018-05-24 10:46:38 -06:00
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constexpr Value UnblockedStorm[int(FILE_NB) / 2][RANK_NB] = {
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2019-06-30 07:22:37 -06:00
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{ V( 89), V(-285), V(-185), V(93), V(57), V( 45), V( 51) },
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{ V( 44), V( -18), V( 123), V(46), V(39), V( -7), V( 23) },
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{ V( 4), V( 52), V( 162), V(37), V( 7), V(-14), V( -2) },
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{ V(-10), V( -14), V( 90), V(15), V( 2), V( -7), V(-16) }
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2016-09-23 11:28:34 -06:00
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};
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2012-03-28 04:44:41 -06:00
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2012-03-28 23:04:44 -06:00
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#undef S
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#undef V
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2012-12-22 03:21:06 -07:00
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template<Color Us>
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2013-06-16 02:51:17 -06:00
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Score evaluate(const Position& pos, Pawns::Entry* e) {
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2012-12-22 03:21:06 -07:00
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2018-03-18 16:38:58 -06:00
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constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
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constexpr Direction Up = (Us == WHITE ? NORTH : SOUTH);
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2012-12-22 03:21:06 -07:00
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2019-09-27 02:18:22 -06:00
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Bitboard neighbours, stoppers, support, phalanx, opposed;
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Rework the "unsupported" penalty into a "supported" bonus
A pawn (according to all the searched positions of a bench run) is not supported 85% of the time,
(in current master it is either isolated, backward or "unsupported").
So it made sense to try moving the S(17, 8) "unsupported" penalty value into the base pawn value hoping for a more representative pawn value, and accordingly
a) adjust backward and isolated so that they stay more or less the same as master
b) increase the mg connected bonus in the supported case by S(17, 0) and let the Connected formula find a suitable eg value according to rank.
Tested as a simplification SPRT(-3, 1)
Passed STC
http://tests.stockfishchess.org/tests/view/5970dbd30ebc5916ff649dd6
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 19613 W: 3663 L: 3540 D: 12410
Passed LTC
http://tests.stockfishchess.org/tests/view/597137780ebc5916ff649de3
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 24721 W: 3306 L: 3191 D: 18224
Bench: 5581946
Closes #1179
2017-08-01 19:36:33 -06:00
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Bitboard lever, leverPush;
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2012-12-22 03:21:06 -07:00
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Square s;
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2019-09-27 02:18:22 -06:00
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bool backward, passed, doubled;
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2014-12-27 02:47:21 -07:00
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Score score = SCORE_ZERO;
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2015-08-04 01:00:52 -06:00
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const Square* pl = pos.squares<PAWN>(Us);
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2012-12-22 03:21:06 -07:00
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2017-06-11 15:31:15 -06:00
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Bitboard ourPawns = pos.pieces( Us, PAWN);
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2013-06-16 02:51:17 -06:00
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Bitboard theirPawns = pos.pieces(Them, PAWN);
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2019-07-25 01:02:26 -06:00
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Bitboard doubleAttackThem = pawn_double_attacks_bb<Them>(theirPawns);
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2019-06-09 06:28:42 -06:00
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e->passedPawns[Us] = e->pawnAttacksSpan[Us] = 0;
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Bonus for double attacks on unsupported pawns
This is a functional change that rewards double attacks on an unsupported pawns.
STC (non-functional difference)
LLR: 2.96 (-2.94,2.94) [0.50,4.50]
Total: 83276 W: 18981 L: 18398 D: 45897
http://tests.stockfishchess.org/tests/view/5d0970500ebc5925cf0a77d4
LTC (incomplete looping version)
LLR: 0.50 (-2.94,2.94) [0.00,3.50]
Total: 82999 W: 14244 L: 13978 D: 54777
http://tests.stockfishchess.org/tests/view/5d0a8d480ebc5925cf0a8d58
LTC (completed non-looping version).
LLR: 2.96 (-2.94,2.94) [0.00,3.50]
Total: 223381 W: 38323 L: 37512 D: 147546
http://tests.stockfishchess.org/tests/view/5d0e80510ebc5925cf0ad320
Closes https://github.com/official-stockfish/Stockfish/pull/2205
Bench 3633546
----------------------------------
Comments by Alain SAVARD:
interesting result ! I would have expected that search would resolve such positions
correctly on the very next move. This is not a very common pattern, and when it happens,
it will quickly disappear. So I'm quite surprised that it passed LTC.
I would be even more surprised if this would resist a simplification.
Anyway, let's try to imagine a few cases.
a) If you have White d5 f5 against Black e6, and White to move
last move by Black was probably a capture on e6 and White is about to recapture on e6
b) If you have White d5 f5 against e6, and Black to move
last move by White was possibly a capture on d5 or f5
or the pawn on e6 was pinned or could not move for some reason.
and white wants to blast open the position and just pushed d4-d5 or f4-f5
Some possible follow-ups
a) Motif is so rare that the popcount() can be safely replaced with a bool()
But this would not pass a SPRT[0,4],
So try a simplification with bool() and also without the & ~theirAttacks
b) If it works, we probably can simply have this in the loop
if (lever) score += S(0, 20);
c) remove all this and tweak something in search for pawn captures (priority, SEE, extension,..)
2019-06-27 01:45:53 -06:00
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e->kingSquares[Us] = SQ_NONE;
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e->pawnAttacks[Us] = pawn_attacks_bb<Us>(ourPawns);
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2012-12-22 03:21:06 -07:00
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// Loop through all pawns of the current color and score each pawn
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while ((s = *pl++) != SQ_NONE)
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{
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assert(pos.piece_on(s) == make_piece(Us, PAWN));
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2019-04-11 08:38:53 -06:00
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Rank r = relative_rank(Us, s);
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2012-12-22 03:21:06 -07:00
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2015-02-24 03:33:40 -07:00
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// Flag the pawn
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2017-06-22 22:03:58 -06:00
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opposed = theirPawns & forward_file_bb(Us, s);
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2019-02-08 02:36:03 -07:00
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stoppers = theirPawns & passed_pawn_span(Us, s);
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2017-04-28 21:33:30 -06:00
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lever = theirPawns & PawnAttacks[Us][s];
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leverPush = theirPawns & PawnAttacks[Us][s + Up];
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2017-04-11 11:50:24 -06:00
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doubled = ourPawns & (s - Up);
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2019-06-09 06:31:16 -06:00
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neighbours = ourPawns & adjacent_files_bb(s);
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2016-04-08 12:05:36 -06:00
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phalanx = neighbours & rank_bb(s);
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2018-12-11 05:47:56 -07:00
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support = neighbours & rank_bb(s - Up);
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2016-04-08 12:05:36 -06:00
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2019-06-09 07:07:36 -06:00
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// A pawn is backward when it is behind all pawns of the same color on
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// the adjacent files and cannot safely advance. Phalanx and isolated
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// pawns will be excluded when the pawn is scored.
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backward = !(neighbours & forward_ranks_bb(Them, s))
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Drop the lever condition for backwards
We can view the patch version as adding some "undermining bonus" for
level pawns, when the defending side can not easily avoid the exchange
by advancing her pawn.
• Case 1) White b2,c3, Black a3,b3:
Black is breaking through, b2 deserves a penalty
• Case 2) White b2,c3, Black a3,c4:
if b2xa3 then White ends up with a weak pawn on a3
and probably a weak pawn on c3 too.
In either case, White can still not safely play b2-b3 and make a
phalanx with c3, which is the essence of a backward pawn definition.
Passed STC in SPRT[0, 4]:
LLR: -2.96 (-2.94,2.94) [0.00,4.00]
Total: 131169 W: 26523 L: 26199 D: 78447
http://tests.stockfishchess.org/tests/view/5aefa4d50ebc5902a409a151
ELO 1.19 [-0.38,2.88] (95%)
Passed LTC in SPRT[-3, 1]:
LLR: 2.96 (-2.94,2.94) [-3.00,1.00]
Total: 24824 W: 3732 L: 3617 D: 17475
http://tests.stockfishchess.org/tests/view/5af04d3f0ebc5902a88b2e55
ELO 1.27 [-1.21,3.70] (95%)
Closes https://github.com/official-stockfish/Stockfish/pull/1584
How to continue from there?
There were some promising tests a couple of months ago about adding
a lever condition for king danger in evaluate.cpp, maybe it would
be time to re-try this after all the recent changes in pawns.cpp
Bench: 4773882
2018-05-08 03:00:51 -06:00
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&& (stoppers & (leverPush | (s + Up)));
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2012-12-22 03:21:06 -07:00
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2019-09-27 02:18:22 -06:00
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// Span of backward pawns and span behind opposing pawns are not included
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// in the pawnAttacksSpan bitboard.
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if (!backward || phalanx)
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{
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if (opposed)
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e->pawnAttacksSpan[Us] |= pawn_attack_span(Us, s) &
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~pawn_attack_span(Us, frontmost_sq(Them, opposed));
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else
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e->pawnAttacksSpan[Us] |= pawn_attack_span(Us, s);
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}
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2019-07-25 01:02:26 -06:00
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// A pawn is passed if one of the three following conditions is true:
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// (a) there is no stoppers except some levers
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// (b) the only stoppers are the leverPush, but we outnumber them
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// (c) there is only one front stopper which can be levered.
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passed = !(stoppers ^ lever)
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|| ( !(stoppers ^ leverPush)
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&& popcount(phalanx) >= popcount(leverPush))
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|| ( stoppers == square_bb(s + Up) && r >= RANK_5
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&& (shift<Up>(support) & ~(theirPawns | doubleAttackThem)));
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// Passed pawns will be properly scored later in evaluation when we have
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// full attack info.
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if (passed)
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2012-12-22 03:21:06 -07:00
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e->passedPawns[Us] |= s;
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// Score this pawn
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2018-12-11 05:47:56 -07:00
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if (support | phalanx)
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2019-03-25 13:04:14 -06:00
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{
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2019-09-27 02:18:22 -06:00
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int v = Connected[r] * (2 + bool(phalanx) - bool(opposed))
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2019-09-24 04:41:45 -06:00
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+ 21 * popcount(support);
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2019-04-23 12:26:58 -06:00
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2019-03-25 13:04:14 -06:00
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score += make_score(v, v * (r - 2) / 4);
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}
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2019-06-09 07:07:36 -06:00
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Rework the "unsupported" penalty into a "supported" bonus
A pawn (according to all the searched positions of a bench run) is not supported 85% of the time,
(in current master it is either isolated, backward or "unsupported").
So it made sense to try moving the S(17, 8) "unsupported" penalty value into the base pawn value hoping for a more representative pawn value, and accordingly
a) adjust backward and isolated so that they stay more or less the same as master
b) increase the mg connected bonus in the supported case by S(17, 0) and let the Connected formula find a suitable eg value according to rank.
Tested as a simplification SPRT(-3, 1)
Passed STC
http://tests.stockfishchess.org/tests/view/5970dbd30ebc5916ff649dd6
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 19613 W: 3663 L: 3540 D: 12410
Passed LTC
http://tests.stockfishchess.org/tests/view/597137780ebc5916ff649de3
LLR: 2.95 (-2.94,2.94) [-3.00,1.00]
Total: 24721 W: 3306 L: 3191 D: 18224
Bench: 5581946
Closes #1179
2017-08-01 19:36:33 -06:00
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else if (!neighbours)
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2019-09-27 02:18:22 -06:00
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score -= Isolated
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+ WeakUnopposed * !opposed;
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2015-03-29 01:24:17 -06:00
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2015-03-28 17:30:46 -06:00
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else if (backward)
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2019-09-27 02:18:22 -06:00
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score -= Backward
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+ WeakUnopposed * !opposed;
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2015-03-29 01:24:17 -06:00
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2019-09-11 12:36:58 -06:00
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if (!support)
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score -= Doubled * doubled
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+ WeakLever * more_than_one(lever);
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2012-12-22 03:21:06 -07:00
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}
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2014-12-27 02:47:21 -07:00
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return score;
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2012-12-22 03:21:06 -07:00
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}
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2013-06-16 02:51:17 -06:00
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} // namespace
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2008-08-31 23:59:13 -06:00
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2012-12-22 03:21:06 -07:00
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namespace Pawns {
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2008-08-31 23:59:13 -06:00
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2014-12-30 02:31:50 -07:00
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/// Pawns::probe() looks up the current position's pawns configuration in
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/// the pawns hash table. It returns a pointer to the Entry if the position
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/// is found. Otherwise a new Entry is computed and stored there, so we don't
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/// have to recompute all when the same pawns configuration occurs again.
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2008-08-31 23:59:13 -06:00
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2014-12-30 02:31:50 -07:00
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Entry* probe(const Position& pos) {
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2008-12-09 08:46:10 -07:00
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2011-12-25 03:50:59 -07:00
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Key key = pos.pawn_key();
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2014-12-30 02:31:50 -07:00
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Entry* e = pos.this_thread()->pawnsTable[key];
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2008-08-31 23:59:13 -06:00
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2012-03-31 05:15:57 -06:00
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if (e->key == key)
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return e;
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2008-08-31 23:59:13 -06:00
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2012-03-31 05:15:57 -06:00
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e->key = key;
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2018-02-20 09:10:37 -07:00
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e->scores[WHITE] = evaluate<WHITE>(pos, e);
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e->scores[BLACK] = evaluate<BLACK>(pos, e);
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2012-03-31 05:15:57 -06:00
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return e;
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2008-08-31 23:59:13 -06:00
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}
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2009-07-24 04:16:18 -06:00
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2018-04-23 01:48:53 -06:00
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/// Entry::evaluate_shelter() calculates the shelter bonus and the storm
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/// penalty for a king, looking at the king file and the two closest files.
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2012-03-28 23:04:44 -06:00
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2012-03-26 05:52:10 -06:00
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template<Color Us>
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2019-08-24 00:16:20 -06:00
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Score Entry::evaluate_shelter(const Position& pos, Square ksq) {
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2012-03-28 04:44:41 -06:00
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2019-07-09 14:03:00 -06:00
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constexpr Color Them = (Us == WHITE ? BLACK : WHITE);
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2012-03-28 04:44:41 -06:00
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2018-07-21 00:17:27 -06:00
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Bitboard b = pos.pieces(PAWN) & ~forward_ranks_bb(Them, ksq);
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2013-07-25 14:23:15 -06:00
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Bitboard ourPawns = b & pos.pieces(Us);
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2012-03-28 04:44:41 -06:00
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Bitboard theirPawns = b & pos.pieces(Them);
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2018-04-23 01:48:53 -06:00
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2019-07-09 14:03:00 -06:00
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Score bonus = make_score(5, 5);
|
2018-05-01 15:50:23 -06:00
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2019-03-31 02:48:27 -06:00
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File center = clamp(file_of(ksq), FILE_B, FILE_G);
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2017-12-04 09:52:31 -07:00
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for (File f = File(center - 1); f <= File(center + 1); ++f)
|
2012-03-28 04:44:41 -06:00
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{
|
2013-10-24 12:34:11 -06:00
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b = ourPawns & file_bb(f);
|
2019-08-14 14:15:41 -06:00
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int ourRank = b ? relative_rank(Us, frontmost_sq(Them, b)) : 0;
|
2012-03-28 04:44:41 -06:00
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|
2017-06-22 22:03:58 -06:00
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b = theirPawns & file_bb(f);
|
2019-08-14 14:15:41 -06:00
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int theirRank = b ? relative_rank(Us, frontmost_sq(Them, b)) : 0;
|
2014-01-10 19:00:17 -07:00
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|
2019-09-21 01:59:32 -06:00
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|
File d = map_to_queenside(f);
|
2019-07-09 14:03:00 -06:00
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|
bonus += make_score(ShelterStrength[d][ourRank], 0);
|
2019-05-12 15:20:51 -06:00
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|
|
if (ourRank && (ourRank == theirRank - 1))
|
2019-08-24 00:16:20 -06:00
|
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|
bonus -= BlockedStorm * int(theirRank == RANK_3);
|
2019-05-12 15:20:51 -06:00
|
|
|
else
|
2019-07-09 14:03:00 -06:00
|
|
|
bonus -= make_score(UnblockedStorm[d][theirRank], 0);
|
2012-03-26 05:52:10 -06:00
|
|
|
}
|
2012-03-28 04:44:41 -06:00
|
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|
2019-08-24 00:16:20 -06:00
|
|
|
return bonus;
|
2012-03-26 05:52:10 -06:00
|
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|
}
|
2011-04-09 12:50:56 -06:00
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|
2012-03-28 04:44:41 -06:00
|
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|
2014-04-13 05:35:58 -06:00
|
|
|
/// Entry::do_king_safety() calculates a bonus for king safety. It is called only
|
|
|
|
/// when king square changes, which is about 20% of total king_safety() calls.
|
2012-03-28 04:44:41 -06:00
|
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|
|
2011-04-09 12:50:56 -06:00
|
|
|
template<Color Us>
|
2018-11-10 20:49:13 -07:00
|
|
|
Score Entry::do_king_safety(const Position& pos) {
|
2012-03-28 04:44:41 -06:00
|
|
|
|
2018-11-10 20:49:13 -07:00
|
|
|
Square ksq = pos.square<KING>(Us);
|
2012-03-28 23:04:44 -06:00
|
|
|
kingSquares[Us] = ksq;
|
2018-12-11 05:47:56 -07:00
|
|
|
castlingRights[Us] = pos.castling_rights(Us);
|
2012-06-17 02:03:05 -06:00
|
|
|
|
2019-08-24 00:16:20 -06:00
|
|
|
Score shelters[3] = { evaluate_shelter<Us>(pos, ksq),
|
|
|
|
make_score(-VALUE_INFINITE, 0),
|
|
|
|
make_score(-VALUE_INFINITE, 0) };
|
|
|
|
|
|
|
|
// If we can castle use the bonus after castling if it is bigger
|
|
|
|
if (pos.can_castle(Us & KING_SIDE))
|
|
|
|
shelters[1] = evaluate_shelter<Us>(pos, relative_square(Us, SQ_G1));
|
|
|
|
|
|
|
|
if (pos.can_castle(Us & QUEEN_SIDE))
|
|
|
|
shelters[2] = evaluate_shelter<Us>(pos, relative_square(Us, SQ_C1));
|
|
|
|
|
|
|
|
for (int i : {1, 2})
|
|
|
|
if (mg_value(shelters[i]) > mg_value(shelters[0]))
|
|
|
|
shelters[0] = shelters[i];
|
|
|
|
|
|
|
|
// In endgame we like to bring our king near our closest pawn
|
2012-06-17 02:03:05 -06:00
|
|
|
Bitboard pawns = pos.pieces(Us, PAWN);
|
2019-04-17 12:38:38 -06:00
|
|
|
int minPawnDist = pawns ? 8 : 0;
|
|
|
|
|
|
|
|
if (pawns & PseudoAttacks[KING][ksq])
|
|
|
|
minPawnDist = 1;
|
|
|
|
else while (pawns)
|
|
|
|
minPawnDist = std::min(minPawnDist, distance(ksq, pop_lsb(&pawns)));
|
2011-04-09 12:50:56 -06:00
|
|
|
|
2019-08-24 00:16:20 -06:00
|
|
|
return shelters[0] - make_score(0, 16 * minPawnDist);
|
2011-04-09 12:50:56 -06:00
|
|
|
}
|
|
|
|
|
|
|
|
// Explicit template instantiation
|
2018-11-10 20:49:13 -07:00
|
|
|
template Score Entry::do_king_safety<WHITE>(const Position& pos);
|
|
|
|
template Score Entry::do_king_safety<BLACK>(const Position& pos);
|
2012-12-22 03:21:06 -07:00
|
|
|
|
|
|
|
} // namespace Pawns
|