[Freegis-list] Suggestions for web mapping system?

[Jo Walsh]

hello rory, just seen your posts here and to consume-resources ...

> What I want to make is a (non-commercial) website to display Wifi
> coverage in the UK, in particular London.  Assuming I gather a list of
> all these wireless transmitter nodes and information about where they
> are and their approximate coverage range I want to draw maps showing
> the nodes and their coverage zones, overlaid upon a street map of
> london. People should be able to click on a node to get various
> details about it, zoom in and out, pan, etc.  
>  - Anyone know anything exactly like this?

we're just starting work on something exactly like this at the moment, as part of a Wireless London project - http://informal.org.uk/wiki/index.php/WirelessLondonTechnicalOverview . It is in consume.net but not of it, ideally i want to make something that can replace the current consume.net node database, and at least stay current with it... expect more detailed braindumps / plans on consume-resources tomorrow 

>  - Anyone know of similar applications using freegis that I could look at?

You could do worse than look at wifimaps.com, which has a lot of pointers to the free GIS packages it was built from: though wifimaps is not source-available, and is US-only. They're interested in collabing on a london project, i think.
 
>  - What freegis software should I use to do this?

we're planning to use PostGIS + mapserver, then the pile of libraries like GDAL and Proj4 that underpin them. The other week i put up an experimental Web Feature Server of the consume nodedb - http://frot.org:8080/geoserver/wfs?request=GetCapabilities shows it. This was my first hands-dirty WFS/GML experiment, and so far i have not found a decent lightweight WFS/WMS client, so i can't send you an instant-gratification URL to view the map - i'd love to find small funding to get an SVG WFS client written for consume. pointers appreciated...

>  - What free data is available for street maps in london?  (preferably
> whole of the UK)

rotflmao. UK map data is 0wned, Crown Copyright by the Ordnance Survey, which is a Trading Fund, a self-supporting company wholly owned by the government. But geographic data is exempt from the Freedom of Information act because it is a "Commercial Interest". There is no free data. http://www.geowiki.co.uk/ were compiling their own (but not copyright-free?) UK maps, but they seem to have gone dead in the last year :/

as a free-time project we are starting work on a free-of-copyright London map and data repository, concentrating on Tower Hamlets and Hackney for now, made from GPS traces with probably a Mapserver interface for annotating and editing features wiki-style. I don't know if there's much prior art on this (we don't want to reinvent the wheel if nesc, but are also quite java-averse). Come help us! We have some nice historic east london maps to digitise, too.      

>  - If full streetmap data isn't freely available, how about just some
> coarse features like parks, main roads, anything that will be better
> than just circles on a blank background?

These streets are made for walking. Also i'd like to get hold of GIS data on such features held (and owned) by local authorities. Problematically, they're so intertwined with Ordnance Survey products like Mastermap, and ESRI backends, that i don't think local authorities know what they do in fact own. There is http://londongreenmap.org , but i want to build a convincing basic demo before we talk to them...

The Open Guide to London - http://london.openguides.org/ - is a wiki spatial recommendation site, which we're hoping to use as both map context and also for a simplest-useful-thing local information service to run with NoCatSplash on the nodes themselves (with the same interface available via the web)...
 
>  - Any recommended reference material for a newbie to GIS that would
> be useful for this sort of application?

There's the start of a project at http://www.eogeo.org/Projects/projects_wiki/FreeGISBook/ - check the recent archives for an OGC tutorial thread. Our dead trees book, due out next year, has a pile of stuff on wireless network mapping and GPS. 

>  - Anything else I should know or questions I should have asked?

to me this is pretty much perfect timing... pls get in touch offlist ;)

xoxo


-jo