[OSM-talk] Name finder: Where Am I?

Andy Robinson Andy_J_Robinson at blueyonder.co.uk
Tue Aug 14 21:08:40 BST 2007

David Earl wrote:
>Sent: 14 August 2007 8:53 PM
>To: OSM
>Subject: [OSM-talk] Name finder: Where Am I?
>Have you ever been zoomed right in to the map and not sure where you
>are? Now name finder can tell you.
>Just click on the "Where Am I" button in the name finder at
>   http://www.frankieandshadow.com/osm/
>and it shows you the location of the centre of the map in context.
>As well as the familiar sentence at the top, the main thing is the
>contextual map "target" on the left. It shows up to six nearby places.
>The challenge of doing this is two-fold:
>Firstly choosing which places out of the sometimes hundreds of
>possibilities. There's a weighting system which scores places according
>to their status (city high, hamlet low), how far away they are, and
>especially whether they are the closest  place of increasing importance
>(so you'll always get the nearest place, whatever it is, but you are
>unlikely to get hamlets further away than towns unless there is nothing
>else to show.
>Secondly, positioning the text on the mini-map so it doesn't all clash
>in a horrible mess or go outside the target. At the moment, it adjusts
>the text, but doesn't take account of the blob that represents the
>place. I could do that too, but at the expense of distributing the text
>further away from its location.
>It's all written as Ajax Javascript (calling on the namefnder for the
>place details, so it would be easy to incorporate elsewhere).
>Experimentally, the current version now recognises UK postcodes and
>tries to look them up. It does this without using a geolocator database
>- it goes to Google to search for the postcode and then tries to extract
>an address from the results, which it then sends to the name finder as
>if you had typed it.
>It's surprising quite how many postcodes get a hit this way, but of
>course not all do. I need to do some further work on the address pattern
>matching especially for addresses that don't have numbers in them - you
>may get some peculiar "not found" messages because of this. Of course,
>the street or whatever it determines has to then be on the map to be
>located by name finder,but if it isn't you'll at least see the address I
>thought I was looking for.
>I have also now checked in the source code, mainly for safety's sake,
>into the Sites directory of svn, after some tidying up and updating
>comments etc. So if you want to see how it works, it is all there now to

As always David, nice work. Especially like the Postcode lookup thinking :-)



Andy Robinson
Andy_J_Robinson at blueyonder.co.uk

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