"There is an increasing trend to enhance user experience utilizing fluid or 'draggable' maps in AJAX and browser-based applications," said J. Kim Fennell, president and CEO of Telcontar, a leading supplier of software and services for the Location-Based Services (LBS) industry, as he announced this week the availability of a comprehensive API allowing developers to more easily develop and implement innovative mapping solutions.

"The tools and platforms available to application developers have been lagging behind the cutting-edge of these new applications. Telcontar's offering delivers powerful tools that ease the design hurdles and enables customers to get to market sooner," Fennell continued.

• The Telecontar API provides a new, open architecture for browser-based mapping and local search applications in AJAX environments, he added: 
  
  "Built on the trusted, scalable technology of Telcontar's Drill Down Server (DDS) geospatial software platform, the offering operates either behind a firewall or through the company's Hosted Web Services capability."

Developers tasked with building AJAX mapping applications, Fennell explained, are faced with many daunting challenges, which he summarized as follows:

• Developing JavaScript that is portable across browsers
• Managing asynchronous XML communication with the server
• Designing a client architecture for loading new map tiles on demand
• Managing map tiles in the context of spatial operations like panning and zooming
• Architecting a scalable server environment capable of coping with massive load differentials compared to a traditional map application
• Designing a map that is differentiated from the competition and with a look-and-feel that represents the provider's brand
• Overlaying route geometry and points of interest for both screen and print operations
• Efficiently handling poor user address input including typos, wrong postal codes and non-existent street addresses.

The centerpiece of Telcontar's API is a powerful new TileGrid element that extends Telcontar's DDS Web Services Map Portrayal service. By adding this element, the URL for each tile in a web-based map tile grid that can be retrieved using a single XML query. Each URL is a set of query parameters that allow the tiles to be rendered just in time, unlike other web-based map tiling systems that pre-render, store and cache every tile at every zoom level for the entire geographic coverage. Telcontar's approach has tremendous advantages such as dramatically reducing deployment costs and simplifying the JavaScript code for functions critical to a fluid user experience like panning smoothly, overlaying points of interest and routes and zooming at arbitrary levels.

This just-in-time tile rendering also provides support for multiple map "styles" which can be changed on the fly instantly producing a very different look and feel of the map. An AJAX application can present the user with a choice of styles which can range from functional (selecting a map style with high contrast and low feature density to facilitate printing) to highly stylized (matching a unique and colorful corporate identity) to humorous (making the map look like an "ancient" map of Middle Earth). Telcontar's DDS offers almost limitless customizability of map color scheme, label placement, feature density at different zoom levels, etc. allowing any organization to customize a look that supports its brand.

In addition, Telcontar's API boasts an advanced freeform address parser that is tolerant of typographical errors with regard to punctuation and style of address. Users now expect to enter an address in a single line without tabbing over separate "street", "city" and "postal code" fields. The DDS Web Services geocoder excels at handling a variety of input formats and provides robust handling of typical user errors such as streets without a street address and wrong postal codes. The geocoder also handles multiple 'locales', meaning that each address can include not only a country code but also a language code. It currently supports nine North American and European countries in five languages; other locales are continually being added.

The framework also has features which minimize client-server communication and client-side code to significantly enhance the responsiveness of the web applications. DDS Web Services XML schema has been carefully crafted to minimize the amount of JavaScript coding while providing cross-browser support for Internet Explorer, Mozilla/Firefox and others.

Qualified developers can download documentation, full-featured sample code and a technical white paper by signing up to the Telcontar Developer Zone at http://developer.telcontar.com/.