Archive for the 'Geometry' Category



In the last few weeks we’ve seen an explosion of people complaining about the lack of asinh() on the Windows version of PHP. We use the asinh() function extensively in Chapter 7 for the custom tile overlays. Admittedly, we didn’t test any of the code against windows versions of PHP (we’re LAMP folks), so until […]

Shapefile Tiles with PHP and GD

Last week, I demonstrated some tools for importing Shapefile data into an SQL database. It’s time to put that stuff to work.
If you’re in a rush, here’s the final demo: translucent state overlays on a Google Map. It’s not the quickest thing in the world, nor is it entirely quirk-free; it exists as an initial […]