The How Zone

Cellphone Locating

Location Technology


location block diagram

This diagram shows the overall flow of location information. It's not perfect; I still have to read the latitude/longitude (lat/lon) from the GPS and type it into the cell phone. After that, though, it's all automated.

These web pages are served from a Linux box at The How Zone's hosting site. Being Unix based it's easy to tap into the scripts and programs that serve up the web pages and incoming mail.

For this project I've modified a file called .procmailrc. This is a configuration file which tells the unix mail program how to handle incoming mail. In this case I've set it up to "pipe" one of the email addresses to a script. Here's a article with more details.

The script takes this incoming email apart, grabs the lat/lon, and writes it to a database along with a time stamp and a text label. When you go to the "Where In The World?" page this information is pulled out of the database and used to render the maps.

I'm experimenting with a couple of map styles. There's a shockwave flash mapping plugin created by Bryan Boyer called IndyJunior. It takes an XML file to describe a series of locations. By chance or by design you can point it at a PHP script that generates the XML, which means it is easy to pull the points out of a database.

Overall I like the program, but it seems a little geared towards East/West travel. You only get an option for setting the width and the configuration program generates the height for you. If you try and change this manually you'll find some strange text/scaling problems.

The other map comes from the old mapserver where I used to work and is here mostly as a backup/comparison. Unfortunately that mapserver's days are numbered and I'll need to find another public, configurable mapping application which takes lat/lon input. Any ideas?

Well, that's enough talk, let's see where I'm at...

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