Simplify TrappedRook

protonspring · snicolet · commit 2d0af36753a2 · 2019-01-22T09:54:10.000+01:00
Simplified TrappedRook to a single penalty removing the dependency on mobility. STC LLR: 2.95 (-2.94,2.94) [-3.00,1.00] Total: 106718 W: 23530 L: 23577 D: 59611 http://tests.stockfishchess.org/tests/view/5c43f6bd0ebc5902bb5d4131 LTC LLR: 2.95 (-2.94,2.94) [-3.00,1.00] Total: 54053 W: 8890 L: 8822 D: 36341 http://tests.stockfishchess.org/tests/view/5c44932a0ebc5902bb5d4d59 bench 3665090
diff --git a/src/evaluate.cpp b/src/evaluate.cpp
@@ -168,7 +168,7 @@ namespace {
   constexpr Score ThreatByPawnPush   = S( 48, 39);
   constexpr Score ThreatByRank       = S( 13,  0);
   constexpr Score ThreatBySafePawn   = S(173, 94);
-  constexpr Score TrappedRook        = S( 96,  4);
+  constexpr Score TrappedRook        = S( 47,  4);
   constexpr Score WeakQueen          = S( 49, 15);
   constexpr Score WeakUnopposedPawn  = S( 12, 23);
 
@@ -377,7 +377,7 @@ namespace {
             {
                 File kf = file_of(pos.square<KING>(Us));
                 if ((kf < FILE_E) == (file_of(s) < kf))
-                    score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.castling_rights(Us));
+                    score -= TrappedRook * (1 + !pos.castling_rights(Us));
             }
         }
 

Original file line number	Diff line number	Diff line change
`@@ -168,7 +168,7 @@ namespace {`
`168`	`168`	`constexpr Score ThreatByPawnPush = S( 48, 39);`
`169`	`169`	`constexpr Score ThreatByRank = S( 13, 0);`
`170`	`170`	`constexpr Score ThreatBySafePawn = S(173, 94);`
`171`		`- constexpr Score TrappedRook = S( 96, 4);`
	`171`	`+ constexpr Score TrappedRook = S( 47, 4);`
`172`	`172`	`constexpr Score WeakQueen = S( 49, 15);`
`173`	`173`	`constexpr Score WeakUnopposedPawn = S( 12, 23);`
`174`	`174`
`@@ -377,7 +377,7 @@ namespace {`
`377`	`377`	`{`
`378`	`378`	`File kf = file_of(pos.square<KING>(Us));`
`379`	`379`	`if ((kf < FILE_E) == (file_of(s) < kf))`
`380`		`- score -= (TrappedRook - make_score(mob * 22, 0)) * (1 + !pos.castling_rights(Us));`
	`380`	`+ score -= TrappedRook * (1 + !pos.castling_rights(Us));`
`381`	`381`	`}`
`382`	`382`	`}`
`383`	`383`