Navigability is the domain of two properties, "from" and "to", that point to linear elements.
No distinction is made between the ends of linear elements, and navigabilities do not tell which ones are concerned.
Ambiguities may be lifted by using the non-linear elements that are inserted between linear elements. The non-linear elements "bear" the navigabilities, and are placed where switches and crossings would be placed. But to know on which side of a linear element some nonlinear element is placed, one has to look up the geometry.
Bottom line:
the number of graph elements to be traversed, for a given itinerary, is doubled (in comparison to ordinary line graphs or node graphs);
the navigable path search is unnecessarily complex, where a RDF reasoner (forward reasoning) or PROLOG routine (backtracking) would suffice;
Topology does not work autonomously, as Geometry is required for disambiguation.
Navigability is the domain of two properties, "from" and "to", that point to linear elements.
No distinction is made between the ends of linear elements, and navigabilities do not tell which ones are concerned.
Ambiguities may be lifted by using the non-linear elements that are inserted between linear elements. The non-linear elements "bear" the navigabilities, and are placed where switches and crossings would be placed. But to know on which side of a linear element some nonlinear element is placed, one has to look up the geometry.
Bottom line: