feat(rails): the wing rails of the frogs of the low section of the blades, as Zu1-60, where the timbers have slide chairs: from 1.5 m before the throat to their ends the foot raised as much as the blades ride, the web shortened, the heads level with the rails beside, forged down to the plain rail along 0.5 m; a wing rail which is the stock rail of a blade too, as in the slips with the blades outside of the diamond, whole along its chairs; the fastening holding only rails raised as much moved up on a pad as wide as it, a raised rail on a fastening with others on a pad of its own

world/SleeperRules.h

@@ -73,6 +73,9 @@ double constexpr check_least { 0.8 };
 double constexpr chair_lead { 0.3 };
 // how far from the stock rail toward its blade the slide plate of a chair is measured
 double constexpr slide_probe { 0.12 };
+// a rail raised less than this goes without a pad under it, and a pad narrower than the second one is left out
+double constexpr pad_least { 0.002 };
+double constexpr pad_narrowest { 0.02 };
 // how far two fastenings on a timber may reach over one another before the check counts them
 double constexpr fastening_overlap { 0.01 };
 // how far from the camera the fastenings are drawn at most