kate/BadFish
1
0
Fork 0
mirror of https://github.com/sockspls/badfish synced 2025-05-01 09:13:08 +00:00
Code Issues Releases Wiki Activity

Space bonus and number of blocked pawns

Browse source 
This patch refines the recently introduced interaction between
the space bonus and the number of blocked pawns in a position.

* pawns count as blocked also if their push square is attacked by 2 enemy pawns;
* overall dependence is stronger as well as offset;
* bonus increase is capped at 9 blocked pawns in position;

passed STC
https://tests.stockfishchess.org/tests/view/5e94560663d105aebbab243d
LLR: 2.96 (-2.94,2.94) {-0.50,1.50}
Total: 29500 W: 5842 L: 5603 D: 18055
Ptnml(0-2): 504, 3443, 6677, 3562, 564

passed LTC
https://tests.stockfishchess.org/tests/view/5e95b383c2aaa99f75d1a14d
LLR: 2.95 (-2.94,2.94) {0.25,1.75}
Total: 63504 W: 8329 L: 7974 D: 47201
Ptnml(0-2): 492, 5848, 18720, 6197, 495

closes https://github.com/official-stockfish/Stockfish/pull/2631

bench 4956028
This commit is contained in:
Vizvezdenec 2020-04-15 04:13:50 +03:00 • committed by Joost VandeVondele
parent 5c58f67126
commit ca4e399ea6
2 changed files with 2 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
src/evaluate.cpp
View file

@ -695,7 +695,7 @@ namespace {
behind |= shift<Down+Down>(behind); behind |= shift<Down+Down>(behind);
int bonus = popcount(safe) + popcount(behind & safe & ~attackedBy[Them][ALL_PIECES]); int bonus = popcount(safe) + popcount(behind & safe & ~attackedBy[Them][ALL_PIECES]);
int weight = pos.count<ALL_PIECES>(Us) - 2 + pe->blocked_count() / 2; int weight = pos.count<ALL_PIECES>(Us) - 3 + std::min(pe->blocked_count(), 9);
Score score = make_score(bonus * weight * weight / 16, 0); Score score = make_score(bonus * weight * weight / 16, 0);
if (T) if (T)

2
src/pawns.cpp
View file

@ -106,7 +106,7 @@ namespace {
phalanx = neighbours & rank_bb(s); phalanx = neighbours & rank_bb(s);
support = neighbours & rank_bb(s - Up); support = neighbours & rank_bb(s - Up);
e->blockedCount[Us] += bool(blocked); e->blockedCount[Us] += blocked || more_than_one(leverPush);
// A pawn is backward when it is behind all pawns of the same color on // A pawn is backward when it is behind all pawns of the same color on
// the adjacent files and cannot safely advance. // the adjacent files and cannot safely advance.