Introduction
- Web map services became a very popular web services following the trend called Web2.0. Those web map services has played a role of a platform for various geographical web content. One of the main functionality of that are offering the map used as a background, and the functionality which superimposes thematic geographical content on it. Occasionally, it may be superimposed on two or more subjects. This can already be called one of the styles of the hyper-document which connects various content on WWW. Nevertheless, there is almost no compatibility in these web map platforms. As a result, those geographical content must depend on specific web map services strongly. This promotes dividing into sections of hyper-documents. So, the time when the WWW standards which realizes the hyper-document for a map should be established may be arriving.
SVG Map is a specification for the map service platform that uses SVG. It achieves essential functions of Map Services as a basic function by fully applying the function of SVG and enhancing a little geospatial metadata.
Differ from other well known web map architectures, a dynamic web server for SVG Map is not indispensable. Of course, it is possible to use it as an option. Because it is possible to construct it as a set of a mere files, even http is not indispensable either. Therefore, SVG Map is also possible stand-alone operation based on the local file system. This characteristic is the same as HTML that is the basis of the Web architecture. It may turn out that this feature is important by investigating the REST architecture thoroughly. And, it might dramatically decrease the cost of the map services.
Protocol
- The basis of the protocol for SVG Map is simply a file access by URL. Basically, SVG Map doesn't restrict anything for it. The scheme of URL might be "file:" though it might be "http:". That is, even query part for http is an option in SVG Map.
Functionality
- Nevertheless, SVG Map achieves following important functions of map services as a basic function without a dynamic server.
- Not only raster map but also vector map support
- Geographic coordinates identification
- Tiled map system
- Hyper-Layering (Mashup of map services)
- Stand-alone operation
History
The basic architecture of SVG Map was designed in 1996. Its part was standardized as SVG1.1 that had been recommended by W3C in 2003. And SVG Map Consortium to promote it was established in 2007, and the reference implementation of the viewer was published.
Specification
- The greater part of specifications for SVG Map are SVG itself. However, the specification that is called "SVG Map Profile" to upgrade SVG for web map services is enhanced. The specification for SVG Map is published at following URL by SVG Map Consortium.
Reference implementation
Client
- It is a viewer because it targets even the stand-alone operation.
Server
- The minimum implementation is a mere map data file. Because the server of the minimum implementation is not dynamic, it doesn't have the program code.
See Also
W3C SVG1.1 specification Geographic Coordinate Systems
Some tools for SVG Map services
