Systems, devices and methods are provided for more efficient use of RAM
and other resources in connection with a route calculation algorithm
which quickly obtains a best or reasonable best path between two
locations. The navigational aid device includes forced layer switching
capabilities. The navigational aid device includes a processor and a
memory adapted to communicate with the processor. The memory has
cartographic data including any number of locations and data indicative
of thoroughfares of a plurality of types connecting certain ones of the
locations. The plurality of thoroughfares are organized in a hierarchy of
detail levels. The processor operates on a route calculation algorithm to
find a path between any two of the number of locations and the route
calculation algorithm dynamically forces switching between different
levels in the hierarchy of detail levels based on a set of criteria.