The Spatial Miscellany

Last month Google released a web browser…Google Chrome. It appears to have debuted to mixed reviews, personally I really like it, but others have had less favourable experience. On the surface, it looks much like any other web browser, but underneath, it’s a bit of an animal.

Google have acquired a new JavaScript engine (V8) written from the ground up to work more efficiently with websites that have large amounts of JavaScript rather than the little snippets of JavaScript which was typical of websites developed when JavaScript was first integrated into Netscape Navigator in the mid 1990s.

Typically JavaScript engines use a dictionary-like data structure as storage for object properties - each property access requires a dynamic lookup to resolve the property’s location in memory. V8 works differently…the first time V8 encounters an object it interprets how the object would be represented as a class, creating a hidden class, which means the next time the object is encountered, its properties can be accessed from memory without the time consuming dynamic look up.

Google give a far more comprehensive introduction to this approach in their documentation of V8, conveniently they use the example of an object common to all GIS developers…a Point.

So What?

The novel approach taken by the V8 JavaScript engine, presents a new opportunity for GIS web developers to work with Points, Lines and Polygons on the web client instead of the web server as is typical of a web based GIS. Using JavaScript in the web browser removes the need for lengthy round trips to the Server, which will make for faster web mapping applications.

Here and now, this will allow web mapping API developers to work with more markers, the typical 100 marker limit of Google Maps applications (and similar web mapping API’s) - is no more; Mike Williams and his team have reported working with as many as 2000 markers when using Google Maps within Chrome.

Chrome isn’t the only web browser to recognize the importance of working with JavaScript heavy web sites, for example, much work is being done on a new JavaScript engine for Firefox. Perhaps in the future, as this approach gains support, spatial analysis functionality can move from the server to the client, which would make for a more engaging web mapping experience?

If anyone is looking for a dissertation project, or has time of their hands, it would be interesting to see the outcome of taking some topological operators (e.g. Java Topology Suite), Google Web Toolkit (GWT) and GWT for Google Maps, all served up with Google Chrome?

Last month saw the annual event that is [Where 2.0], a conference hosted by O’Reilly in San Francisco. Over the past couple of years it’s been somewhat of a landmark event in the geospatial calendar, often playing host to a raft of new and exciting location aware technology…Woodstock for Neogeography?

I’ve never managed to attend the conference, but always made a conscious effort to follow online; this year it felt different, no headline announcements or cool new products, and very little chatter.

One announcement that did grab my attention was made by John Hanke from Google during the ESRI\Google keynote (you can watch the keynote here). Hanke remarks that Google have provided access, via their search API’s, to the Google ‘GeoIndex’ – an index of results returned by Google robots as they crawl the web for geospatial content. On the surface, this is significant news, but it seems to have received only little comment.

Hanke suggests the Google search API’s will provide access to the “content, attribution, linkbacks and the urls” that make the geoweb…but where are the underlying resources, where are the KML files?

Barry Hunter has knocked up a useful php script that queries the GeoIndex and nicely formats the JSON response. Try it out and you’ll notice you get a handful of Google Maps url’s, but no links to the underlying resources? Hopefully, there is more to come; providing access to the GeoIndex, and the underlying content files, really would move the ‘geoweb’ forward.

Google Summer of Code (GSoC) is a program that offers student developers cash to write code for various open source projects. Google will be working with several open source, free software, and technology-related groups to identify and fund several projects over a three month period.

I think it’s a great opportunity for students, surely better than spending many summer months obsessing on an esoteric thesis that will never see the light of day – perhaps that was just my experience? Christopher Schmidt and others have offered their support for students wishing to further develop OpenLayers, it would be great to see some of the stuff on the list tackled.

Last week Google announced an umbrella API for social networks, OpenSocial. On the back of their announcement, Google have released a preview of their API. Thumbing through the API preview I expected to see some elementary support for location, perhaps a “city” or “hometown” tag that developers could geocode, so I was pleasantly surprised to find what appears to be another implementation of GeoRSS…

That is the question asked in the July\August edition of MIT technology review. In a series of articles, the magazine suggests that a world of virtual earths and mirror globes will eventually replace the internet – a MetaVerse. This idea seems to be flavour of the month with similar articles appearing in other magazines (e.g. business week) and numerous blogs (including the prolific DigitalUrban) throughout the last couple of months.

Technology Review contributor, Wade Roush, talked with Google Maps director John Hanke about the feasibility of the MetaVerse. They suggest a logical first step towards the ‘MetaVerse’ is the representation of real geography, typical of mirror worlds like Google Earth (and ArcGIS Explorer), in virtual worlds like Second Life. Increasingly examples of this can apparently be found in Second Life, for example, researchers at the University of Denver host a dynamic NOAA weather map on a Second Life island. Roush and Hanke suggest the second and marginally more challenging step will be the representation of second life and its avatars in mirror worlds like ArcGIS Explorer and Google Earth. Well with the new OpenGL custom drawing capabilities in ArcGIS Explorer, that’s now possible. The wind vectors in the following video clip are rendered in OpenGL…

Why would you want to render second life avatars in ArcGIS Explorer? I really don’t know. But you can, and what’s more, you can now render any other OpenGL in ArcGIS Explorer. More usefully it may be the output of specialised software unique to your industry that you use to model, wind farms, air pollution, wind vectors or telecom coverage.

Pondering the potential of this new functionality, I discovered OGLE from eyebeam research. OGLE intercepts the OpenGL calls any application makes to the OpenGL library, using this technology it should be possible to extract anything that is drawn in OpenGL – as OpenGL, for example, the building layers in Google Earth, or even the avatars in Second Life. Using the new events and methods exposed in the new ArcGIS Explorer API, such data could now be rendered in ArcGIS Explorer (copyright permitting?).

James, Kirk and Keith remark on the latest release of ArcGIS Explorer elsewhere; and more info on the latest ArcGIS Explorer release can be found on the team blog and at the resource centre.