From 0d33466bcd84d9d58ea7049b224f375ba6a51221 Mon Sep 17 00:00:00 2001 From: =?utf8?q?St=C3=A9phane=20Nicolet?= Date: Mon, 5 Dec 2016 18:49:07 +0100 Subject: [PATCH] Pawn flank attacks This patch tweaks some pawn values to favor flank attacks. The first part of the patch increases the midgame psqt values of external pawns to launch more attacks (credits to user GuardianRM for this idea), while the second part increases the endgame connection values for pawns on upper ranks. Passed STC: LLR: 2.95 (-2.94,2.94) [0.00,4.00] Total: 34997 W: 6328 L: 6055 D: 22614 and LTC: LLR: 2.96 (-2.94,2.94) [0.00,4.00] Total: 13844 W: 1832 L: 1650 D: 10362 Bench: 5884767 --- src/pawns.cpp | 2 +- src/psqt.cpp | 12 ++++++------ 2 files changed, 7 insertions(+), 7 deletions(-) diff --git a/src/pawns.cpp b/src/pawns.cpp index 71ec3443..6e564c9d 100644 --- a/src/pawns.cpp +++ b/src/pawns.cpp @@ -197,7 +197,7 @@ void init() { { int v = (Seed[r] + (phalanx ? (Seed[r + 1] - Seed[r]) / 2 : 0)) >> opposed; v += (apex ? v / 2 : 0); - Connected[opposed][phalanx][apex][r] = make_score(v, v * 5 / 8); + Connected[opposed][phalanx][apex][r] = make_score(v, v * (r-2) / 4); } } diff --git a/src/psqt.cpp b/src/psqt.cpp index 41a9b499..3addc288 100644 --- a/src/psqt.cpp +++ b/src/psqt.cpp @@ -39,12 +39,12 @@ const Score Bonus[][RANK_NB][int(FILE_NB) / 2] = { { }, { // Pawn { S( 0, 0), S( 0, 0), S( 0, 0), S( 0, 0) }, - { S(-16, 7), S( 1,-4), S( 7, 8), S( 3,-2) }, - { S(-23,-4), S( -7,-5), S( 19, 5), S(24, 4) }, - { S(-22, 3), S(-14, 3), S( 20,-8), S(35,-3) }, - { S(-11, 8), S( 0, 9), S( 3, 7), S(21,-6) }, - { S(-11, 8), S(-13,-5), S( -6, 2), S(-2, 4) }, - { S( -9, 3), S( 15,-9), S( -8, 1), S(-4,18) } + { S(-11, 7), S( 6,-4), S( 7, 8), S( 3,-2) }, + { S(-18,-4), S( -2,-5), S( 19, 5), S(24, 4) }, + { S(-17, 3), S( -9, 3), S( 20,-8), S(35,-3) }, + { S(- 6, 8), S( 5, 9), S( 3, 7), S(21,-6) }, + { S(- 6, 8), S(- 8,-5), S( -6, 2), S(-2, 4) }, + { S( -4, 3), S( 20,-9), S( -8, 1), S(-4,18) } }, { // Knight { S(-143, -97), S(-96,-82), S(-80,-46), S(-73,-14) }, -- 2.39.2