Friday 9 March 2007

GMM - KML Files

Some good news, I was able to get GMM to load a KML file off of the web (one of the tmpegML -> KML files I created). It seems to only like files that have placemarks in them, I tried loading a file that was record of a trip I took last weekend, but it wouldn't load.

Over the weekend, I'll try to clean up my tpegML -> KML convertor. I think I'm only going to include the start point (though maybe both points if it's a "both directions problem") to cut down on file size (which looks a lot like what gTraffic.info does)

GMM - It Crashed

Google Mobile Maps crashed when I exited, loosing my favourites. I hope that doesn;t happen too often (or at all, really)

Google's Mobile Maps.

I've installed Google's Mobile Maps on my Motorola L6. It's a Java Applet (with versions for Windows Mobile and Palms also available), though it looks like there are tailored versions of the applet for different phones. Officially, it doesn't support the UK ("Now you can use Google Maps in Australia, Canada, France, Italy, Germany, the Netherlands, Spain, and the United States."), but it seems to work fine.

I'm not convinced by Google's directions - the route it gives between my flat and my parent's house is patently insane (the directions it gives will get you there, eventually). This isn't the first time I've had doubts about Google's directions (there's a section of the M25 it seems to completely ignore), so I doubt this is a problem only with the mobile version of the maps (and checking the route on the desktop version - it's the same route). I can sort of see how it goes wrong - it looks like it's calculating the shortest route (but even then, it's not the shortest possible route), the only thing I can think of is that it's the ideal route if there was no traffic involved. One day, I might try the route at 3am, just to find out.

There is one issue with the directions that is directly related to the mobile version of the maps. I stored the locations of both my flat and my parents house as favourites (I searched by postcode, stored that as a favourite and then renamed them to Flat and Home, respectively). When I try to get directions using the stored favourites, my start position is somewhere in Essex.

Other than directions of dubious quality, the rest of Google Mobile Maps works well. It has the most of the features as the desktop version, such as the satellite view - but there doesn't seem to be overlay mode. It can eat up data though (especially satellite imagery) - so it puts Orange's "all the data you can eat (up to 25 MB) for a £1" to good use. It's easy to use, and both maps and sat images display well, even on the L6's tiny screen. Finally, and possibly most importantly, it's free (as in beer).

Wednesday 7 March 2007

Google Maps Send to Car

If you live in Germany, drive a BMW and have BMW Assist, you can now send maps from Google DE directly to your car.

tpegML to Atom

Since last weekend, in the evenings I've been working on converting tpegML from the BBC's traffic site into an Atom (with embedded geoRSS) feed (I've also had some limited success converting to KML).

So far, I've found tpegML to be an absolutely horrid data format. One thing that doesn't help is that specifications to the format are locked away by the ISO (so the format is "open", but you can't just get the specs off a web site - not a great way to encourage web wide adoption). Whoever designed it went overboard on making the format language neutral, so you end up with elements like <location_descriptor descriptor_type="&loc3_32;" descriptor="M4; 25">. Fortunately, entity definitions are provided by the BBC - but it still is more pain than it's worth. The schema itself is a bit odd, where elements that you think would be children of other elements are siblings instead. BeautifulSoup comes to the rescue - it turns tpegML into something a bit more sane.

So far, I've been able to reasonably re-create the BBC's own RSS feed (at least for motorway data), so I've turned to embedding the geoRSS data, where I've run into more oddities. There are 2 formats of geoRSS - geoRSS and geoRSS Simple (plus there's a geo tag from the W3C that is slightly different but has been deprecated, but looking at some blog posts, is still commonly used). Personally, I like the old W3C format as it has explicit elements for latitude and longitude. I'm somewhat unimpressed by how geoRSS (and KML) dump both values into a single element. But what's worse is that geoRSS doesn't support multiple points in a single item (outside of the concepts lines and boxes). This is an oversight, as far my use of geoRSS is concerned, as I have the need to have a single item with more than one point, where those points are related, but they are not a part of a line. For now I think I'll try and use a line, but I'm not really satisfied. I might just extend atom myself (as I'm probably the only person who wants this traffic data in atom anyway)

Welcome To Scot's Geo Log

Welcome To Scot's Geo Log, which will detail my "geo" (GPS, Google Earth, KML, etc) adventures (like how my VOIP log deals with telecoms)