LEVEL OF DETAIL

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Illustration

Finding an address in long streets can be very difficult and time consuming when not knowing the house number.

Context

…you have decided to implement a function to create new routes - CREATING NEW ROUTES.

Before letting the user enter information about start, destination and interstations of a route, you have to define a level of detail for that information first.

Problem statement

How can an appropriate level of detail for a map and the included address data be defined?

Problem description with forces

Different applications of navigation systems need different levels of detail of the used maps. Whereas slow-traveler navigation systems have special constraints that require very detailed maps (see SLOW-TRAVELER-NAVIGATION), for an in-car-navigation system it is not necessarily important that every single house can be navigated to.

In general the highest level of detail should be provided wherever possible, of course. But as sometimes hardware limits the amount of data that can be stored some details have to be left out.

Examples

Desktop route planning applications like Map&Guide [1] provide very detailed maps that range from continent overview to street level of cities. As the data is stored on CD-ROMs or DVD there is almost no limitation in the level of detail.

Navigation systems for mobile devices on the other hand most of the time have limitations in their storage capacities. For that reason either the level of detail is reduced or the size of the map is limited to a special region or only a single city.

For example, Falk City Guide [2] provides detailed maps for a single city only. Though there is an additional map of Germany available, this map contains only the most important information for orientation.

In SMARTPATH City [3] there are only maps for a city or region available. These maps contain details at street level but cannot be used for country-wide navigation. For the latter there is a different version of SMARTPATH available - SMARTPATH Trip [4]. This system provides low detail maps that contain information of a whole country.

Solution

Therefore:

Provide as much detailed maps as possible. If due to hardware limits (like memory or storage capacities) some details have to be left out, think about what information is needed most of the time depending on the users and the application domain.

Do not display all information at once but reveal them if needed.

Diagram

References

After you have chosen the level of detail for providing a route planning function, you should think about possibilities how users can enter DEPARTURE AND DESTINATION as well as INTERSTATIONS.

Literature and Links

1. Map&Guide GmbH; http://www.mapandguide.com
2. Falk City Guide CeBIT Hannover Edition, Version 1.0 (Build Mar 7 2003); http://www.falk.de
3. SMARTPATH City, Version 1.10 (161); http://www.navman-mobile.com/html/city-pc.htm
4. SMARTPATH Trip, Version 3.10 (138); http://www.navman-mobile.com/html/trip-pc.htm