Use of vector and raster tiles for middle-size SVG's mapping applications

Benjamin Campin - GIS/SVG Application Developer - DBx Geomatics Inc.

Because of the complexity of the geographic information, many of middle-size webmapping application need a web server in the background to dynamicaly incorporate vector or raster information in the user's interface.

The aim of this paper is to present a technical solution that uses tiles (vectors and raster) for middle-size SVG mapping application with no web server.

Using the getURL and parseXML methods of the Adobe's SVG plugin and Batik SVG viewer (squiggle), the pieces (tiles which are in separate svg's files) of document to be displayed to the user are called efficiently

Two different implementation will be demonstrated:

The vector's tiles presented in the examples are created by SVGMapMaker software, combined to MapInfo Professionnal (a GIS software).

Concerning the raster tiles, we will see that any image slicing software for web publising could do the job.

This paper will go depth to the Ecmascript's code of the intersection of the rectangle of the users's viewbox, and the tiles.

An example that illustrate the raster tiling is on-line Canadian geographic (Canada and the World) needs Adobe's SVG plugin. This SVG application is dealing with four layers of detail with a total of 117 raster files (total of 12 MB).

DBx Geomatics inc.
email: bc@dbxgeomatics.com
web: http://www.dbxgeomatics.com