Map Layers – Making GPS Systems Useful
11 May 2010 Jason 0
For people who think a GPS device is really just an on-screen map, then they may not know about map layers, the secret to making GPS systems highly functional and useful to a huge range of industries and professions.
When you think of a paper map, you imagine a two-dimensional map that offers basic road or topographic information. A paper map is static, never changing and can quickly become outdated, not to mention difficult to fold.
In contrast, a GPS device uses electronic maps as the basis for its location services. Electronic maps are regularly updated and delivered to a user via a website (e.g. Google Maps) or a mobile device (e.g. TomTom, Garmin etc.). Electronic maps are flexible, allowing users to zoom in or out to automatically change the scale and detail of the map. Because they are delivered electronically, they are portable, convenient and can be used in a huge variety of different ways – both for work and play.
Map Tiles – The foundation data for GPS systems
The electronic map data is generally provided by a third-party supplier such as NAVTEQ or Tele Atlas. These companies collect, store and deliver map data to other businesses such as Telogis. Telogis then bundle this with their geospatial mapping engine, Telogis GeoBase.
Of course, for someone using a mapping application over the internet it would be impractical to deliver the entire map as a single file, in much the same way that having a map of the entire world in your car would help you find a street in a nearby neighborhood. For a paper map you will generally have a map that covers a smaller area, large enough for you to see and use but small enough so it can be carried around or stored in your car door pocket or glove box. Similarly, electronic maps are delivered in pieces, otherwise known as tiles.
The map tiles that are delivered, let’s say for someone using it over the internet, are supplied on an ‘as needed’ basis to make sure loading times are as short as possible. If the route you are taking extending beyond the current tile you are viewing, the next, adjacent map tile will be loaded. The process of tile loading is as seamless as possible, with images loading in the background, to ensure you as the user, barely notice it’s happening.
In some instances, all the map data may be delivered in one go rather than being sent as map tiles. Telogis GeoBase users are provided with the whole map file whereas an online application such as Telogis Fleet, uses the GeoStream feature of GeoBase, which streams the map data as tiles to the end user to the improve the speed and usability of the software.
Map Layers – Custom map data is the key to useful GPS systems
An electronic map that provides the same information as a basic paper map doesn’t offer a lot of additional value to the user. Fortunately for us, electronic maps take cartography to the next level and offer levels of customization that make it a vital tool in business today.
And it’s all achieved with map layers.
Map layers are essentially custom map elements that are superimposed over the top of an existing topographical map. Sure superimposed map data isn’t new; John Snow was doing it in the 19th century to trace the source of a Cholera outbreak but the way it is being used in the current electronic age is making map layers an indispensable part of location-based technology.
There is no limit to the different types of map layers available, and some map layers are very specific to a particular industry. For example, a logging company may have maps covering their forests and superimpose over it a map layer showing all the private forestry tracks so they can navigate their vehicles in the area. Or a fire department may overlay a map layer detailing the location of all the fire hydrants in the town they service. Custom map data is also referred to as a geographic information system or GIS.
Map layers designed specifically for mobile workers may include information not usually found on a traditional paper map. Telogis GeoBase, which uses supplied map data, includes some built-in map layers to make sure that any applications built using it are functional, rich and engaging.
- Traffic data – Real-time, streamed traffic data can help drivers (or route planning software) to make intelligent decisions on the fastest route to take.
- Speed limits – Since posted speed limits vary depending on where a driver is, live map data using GPS location technology can keep whoever is behind the wheel informed on the current speed limit.
- Road restrictions – Different roads may restrict certain types of vehicles or different driving maneuvers such as left-hand turns. A road restrictions map layer can help a driver know which routes they can and can’t take.
- POI (Points of Interest) – POIs will differ depending on the driver as what might be of interest to one person (truck weigh station) may not interest another. POIs on a map can allow a driver to route directly to a destination even when they don’t know the address (e.g. take me to the nearest bank ATM).
As map technology grows and expands in the varied and detailed information it can provide users, you can expect that very soon, customized map layers will be an indispensable part of your day, either at work or at play.