Navigating Objects - Programming GPS and OpenStreetMap Applications with Java - page 123

Chapter 9

Navigating Objects

9.1 Introduction

Although moving objects reflect a realistic trace on the map, they have
no freedom to deviate from the prerecorded or live data. By extracting a
route from a digital-map network, the navigating object can make a choice
at the maneuver points.
A clean network with a related administrative database enables a user to
extract a well-defined route from the network. Again, we can close the door
to all of the theory of networking digital maps and finally make use of the
products created on a higher-level to calculate routes. Route-calculation
algorithms assist the user to navigate through a network by evaluating the
best possible route. A GameMap is developed to traverse the graph of the
NavigableMap produced in the last chapter.
Current navigation systems are dedicated computers used to collect all
data relevant for a route calculation according to parameters and exter-
nal conditions. To get an idea of dynamic route calculation, a Navigator
will visualize a number of objects navigating between the larger cities of
Germany.

9.2 Navigation Systems

One of the first built in navigation systems was introduced in 1996, when
digital maps covered only a few major cities and their connections. The
navigation systems operated completely off line, and the map data (PSF)
was provided on external media. Today, most industrialized countries are
nearly one-hundred percent geocoded, the devices are scaled down to per-
sonal navigation devices (PNDs) and are moving to smart phones with the
ability to deal with dynamic integration of additional online content to
alter a route.
The amount of constantly growing map data and the restricted mem-
ory of handheld devices suggest distributed functionality between on- and
off-board calculations on a server. The value-add will be location-based

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