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I gave a talk at Google I/O in June this year with fellow Googler Brendan Kenny, on the topic of Spatial Data Visualization using the Google Maps API:

If you’re interested in playing with the demos yourself, follow along with the slides, and perhaps even take a look at the source code!

Crossposted from Google Geo Developers Blog

With a paper map, you can truly make it your own by getting out a pen or a pencil, and adding your own annotations to it. You could circle all the museums that you want to visit, or trace the route that you will take on your road trip.

Maps API applications can now offer users this sort of tactile interactivity using the new Drawing Library. The Drawing Library provides a toolbox which enables users to draw markers, lines, and shapes on the map, much as they would in any drawing application. The tools can be used for collecting annotations from users, or for selecting regions to search or highlight. Applications can listen for events when overlays are added and respond accordingly, such as issuing the search query or saving the annotations to a database.

Shapes on a map, including shapes users have just drawn using drawing tools, can also be made editable so that users can modify or correct them. For example, the user could change the bounds for a geospatial query with the drag of a mouse. The Polyline, Polygon, Circle, and Rectangle classes have a new editable property, which toggles the visibility of control points on these shapes.

For more information on using the drawing library and editable shapes, please refer to the Maps API documentation. The Maps API forum is a great place to discuss these new features, or raise any other Maps API issues that you may have. We hope that these new features will result in even greater interactivity for applications built on top of the Maps API.

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At around 3am Sydney time, YouTube went down:

Google’s monkeys are still slaving away at it as I write this. And it looks like it’s just affecting Australia:

For future reference, if you’ve got a box outside Australia with ssh access, you can always quickly set up a proxy like so:

ssh -D 1337

This sets up a SOCKS proxy on localhost (your own computer) at port 1337 (substitute port number to taste) – then simply point your browser at it. With this, I verified that the YouTube outage at the very least didn’t affect the United States, by ssh-ing into, which is hosted in the US.

Related post from a while ago: Silverhawks: Getting around content restrictions. (Using -D with ssh is easier than the method with Privoxy mentioned in that post, though.)

Happy Australia Day.

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Optus, Optus, Optus. You really like screwing over your customers right? I really didn’t appreciate having to work out why my home network printer stopped working right in the middle of exams — because you screwed with DNS to earn a few easy quid. (Same goes for you, Telstra.)

19 Nov 2009 | No comments

The International Free and Open Source Software Law Review – about time, although, of course, it’s more for lawyers than FOSS enthusiasts.

18 Oct 2009 | No comments

When the SUITS web server went down a couple of weeks ago, the skies darkened and there was much outpouring of grief.

In the words of one committee member:

At approximately 1445 today, suitsbeta shut itself down, never to wake up again. Attempts were made to revive it by powering it up, but alas it failed to POST. Our thoughts go out to its family and friends.

Another expressed regret:

It was nice knowing you suitsbeta. We’re sad that you toiled alone and in sickness for your last few months.

But it was well-loved:

Although I did not log into suitsbeta many times I did appreciate the machine and the contribution it made to this society. Few can claim to have sustained such continuous service to the society and its members, never asking for recognition or relief.

However, death can give rise to hope:

The memory of suitsbeta’s cranky innards will live on in the cron messages, reboot requests, and database errors that pepper my email archives. May the metal be reborn and the warnings silenced.


Update: It turned out to be a problem with the Lightbox plugin I was using. I’ve replaced it with another plugin that provides similar functionality, and the error has now gone away. Lesson learnt: having many scripts on the same page can be a recipe for disaster. Thanks Nuffnang for helping me work through this issue.

I recently added a Nuffnang ad to the sidebar — I hope none of you mind too much!

Anyway, all was going well until Internet Explorer threw a spanner into the works (well, well, which browser always throws a spanner into the works?).

It appears that on Internet Explorer 7 and earlier (using my particular WordPress template at least), the addition of the Nuffnang ad code can cause the page to fail to load with an Operation aborted error:


This error is particularly troublesome: after the hopelessly uninformative dialog box is dismissed, the page disappears and gets replaced by a navigation error page. (Thankfully, this hideous behaviour was changed in IE8, which might explain why I didn’t pick it up earlier as that is my installed version. But it still begs the question, why do people insist on using Internet Explorer?)

I’ve let Nuffnang know about the potential problem, and with any luck, it will be resolved soon.

In the meantime, I’ve made some changes to the ad code:

What this does is that it first checks whether the browser is Internet Explorer. If it is not, the Nuffnang script can be called upon directly. If it is Internet Explorer, an iframe displaying /nuffnang.html is added to the document. /nuffnang.html just contains a copy of the ad code as provided by Nuffnang placed into an otherwise blank HTML page.

Why? Isolating the Nuffnang ad code in a blank page by itself seems to avoid the error conditions as described by KB927917. But even if an error were to develop, the error would be confined to the iframe and the rest of the page can still be displayed.

If you’re having similar difficulties, give the above a go and see whether it works for you.

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I recently started doing software development on a casual basis for GPlates, at the School of Geosciences, University of Sydney. Think back to high-school science class where you learnt about Pangaea and Gondwanaland and how the Earth’s tectonic plates have ever-so-slowly shifted over millions of years. GPlates is software that allows scientists to “wind the clock back” on these plate movements and visualise what the Earth might have looked like all these years ago. It’s open-source, so if you’re curious, grab a copy and play with it.

I’m quite glad to have met the GPlates team. It’s difficult, I think, to find quality software engineering in Australia, and GPlates development is led by a bunch of developers who are passionate about writing quality, well-designed, best-practice C++ code. It’s certainly not your average in-house or academic research software. And it sure is more intellectually safisfying than working in corporate IT.

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I just got my Google Wave developer sandbox account! I can’t wait to play with it, but I think I’m going to have to put my excitement on ice until I finish my exams in a week’s time. Boo.


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