Implementing an integrated SVG application for real time, dynamically generated Internet mapping

SVG has immense potential for Internet delivered maps, combining high quality visualisation and good user interactivity. These advantages make it overwhelmingly superior to raster based image maps, but the advantages of SVG are less when compared to "Internet-GIS" solutions such as ArcIMS and MapXtreme. These are also vector-based and scalable, and being relatively mature solution, provide a completely integrated technology. The relative benefit of SVG mapping compared to these products lies in its flexibility, low cost and potential to adapt easily and quickly solutions developed for other members of the XML "family".

Nevertheless, practical implementation of SVG mapping poses many challenges. The most difficult of these is for the delivery of real-time dynamically generated maps, wherein data from an active database is rendered in the browser. This is the requirement when Internet mapping goes beyond the display of static maps, being used as a tool for data integration, visualisation and part of real-time decision support systems.

We faced such a requirement when asked to develop a system to assist the ministry of agriculture (DEFRA) in Great Britain in the control of a disease of cattle (bovine tuberculosis), wherein data from a number of sources needs to be combined and delivered to field veterinarians. This requires a large number of maps to be generated, along with charts, meta-data and guidance for interpretation. The solution we successfully developed uses a number of elements, of which while all are well known within the SVG community, less commonly have been successfully combined into a single complex application.

The development of this application will be described in detail in our session. In brief, it consists of

Currently, the only XML-based technology lacking is the use of XSLT, which reflect the difficulties implementing this solution in a Microsoft environment. However, XSLT offers such overwhelming advantages for greater user inter-operability, that this will be the focus of our development effort in the coming months.