In the previous chapter, we wrote a complete implementation of the DISTAL system that works as advertised: a user can choose a country, enter a search radius in miles, click on a starting point, and see a high-resolution map showing all the place names within the desired search radius. Unfortunately, the DISTAL application is lacking in a number of areas, and even a cursory look at it will reveal some major problems. In this chapter, we will work on solving these problems. Along the way, we will:
Learn about the anti-meridian and solve the problems it can cause when working with latitude and longitude-based coordinates
See how to add a zoom feature to our CGI scripts
Discover the consequences of working with huge polygons, and how you can improve performance by breaking these polygons down into smaller pieces
Make huge improvements to the speed of our DISTAL application by splitting the shoreline data into tiles and displaying a single tile rather...