fix(sleepers): the wing rails on the timbers as they're bent out: the rails of a track taken in their parts between the cuts at the crossings, as they're laid, a part going on over the gap at an obtuse crossing where its check rail lies; three rails or more close beside held by the fastening of two rails covering the most of them first, then those before and after it, one holding more rails than its seats not narrowed; a rail lying on the brace of a chair beside takes the brace away; a plate cut short at the fastening beside from where its narrowing left it

world/SleeperFastenings.h

@@ -31,6 +31,7 @@ struct fastening {
     float pivot { 0.f }; // the x of the part kept in place as it's narrowed
     float shift { 0.f }; // along its x, how far the pivot is moved
     bool both { false }; // the fastening of two rails close beside each other, neither with a check rail of its own seated
+    bool whole { false }; // holding more rails than its seats, out to its ends: not narrowed
     // where an x of the part lands along its across, at the scale
     double placed( double const X, double const Scale ) const {
         return pivot + shift + Scale * ( X - pivot ); }