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Telmap

Tile-based map rendering systems draw large numbers of square map tiles, creating each one as a bitmap, and serve them to an AJAX-based web page that stitches the tiles together to form the map the user sees. The server has to render and cache many thousands of tiles at ten or more scales. Tile systems are used by many large mapping systems such as Google Maps and OpenStreetMap.

Telmap's servers are 64-bit systems running Solaris. CartoType was built for this platform without difficulty, demonstrating its portability and lack of dependencies.

Server-side rendering doesn't suffer from the same speed constraints as rendering on a mobile device, allowing more complicated map styles to be used. CartoType's style sheet system allows the use of advanced techniques like

• inhibiting the use of identical labels within a certain distance, so that long roads are labelled only at suitable intervals, even when composed of many short segments
• showing traffic density by adding highlight lines to a road, over it or parallel to it, and with optional repeating symbols such as arrows
• adding attractively rendered symbols to indicate tunnel mouths, bridges and one-way roads; these symbols can be coded in dynamically rendered SVG.
• making map labels clearer and distinguishing different parts of a name by using multiple fonts, styles and colors in a single label

Naturally, CartoType ensures that adjacent tiles meet cleanly, with no discontinuities, truncated labels, or half-drawn icons.