Tag Cloud « Time rolls on

Tag Cloud

01Dec08

I discovered this web site today : http://www.wordle.net/
It proposes some nices layouts to display tag clouds.
The display is made with a java applet, but I’m sure we could do pretty the same thing using SVG. I used SVG in one of my previous projects 2 or 3 years ago and I really like how simple it was to generate complex vectorial drawings. The only issue was that to display SVG files in a browser we had to use an external plugin : adobe svg viewer. At this time, this plugin was not supporting the last svg specification and was going to be stopped (I suppose it is effectively now).

SVG might have lost some interest now with complex javascript framework like DOJO or EXT, and FLash/Flex, but … well I like SVG, may be I’m a little bit nostalgic. I thing one of the main advantage of SVG is that it’s XML based language. So on the server side it’s quite easy to generate and also to debug (any XML editor to check the syntax or SVG editor to look at the rendering, eg Inkscape). And the task to insert some semantic information into this XML cloud using RDFa or eRDF would be hugely simplify.

To generate a tag cloud, which is mainly a font centered diagram, SVG must do the job quite easily and keeping at the same time the application layers well separated.

Now the last browser generation supports SVG natively and for the others a framework like DOJO or EXT is able to encapsulate it and emulate the rendering using the specific browser capabilities. I should try to implement a composant to render different tag cloud layouts with SVG just for fun. I try to found a suitable algorithm to calculate tags positions but it should not be so hard to have a simple one to have a first drop.

Some links to have a look at
http://arxiv.org/abs/cs.DS/0703109
http://dotnetaddict.dotnetdevelopersjournal.com/tw.htm
http://semanticvoid.com/blog/2006/01/06/tag-cloud-font-distribution-algorithm/
http://poeticcode.wordpress.com/2007/01/27/tag-cloud-algorithmlogicformula/
http://internetducttape.com/2007/02/22/tag-cloud-generator-for-wordpresscom/
http://www.citebase.org/abstract?identifier=oai%3AarXiv.org%3Acs%2F0703109&action=citeshits&citeshits=cites

At least I took time to write a post even if it’s not THE post of the year…