Tuesday, August 29, 2006

SecondLife Geotagging

There is lot of noise today in blogs about Yahoo adding geotagging support to Flickr. If you are not familiar with the concept - it is just a way to add geographic coordinates where photo was taken.

I think we should all come up with a common way to geo-tag places in second life. This information could be used to tag screenshots or videos from SL uploaded to the web, blog posts discussing (or posted from) certain SL location, etc.

Quick google search have not revealed any earlier proposals for second life geotagging, so I am going to go ahead and propose one here:

Following four tags could be attached to the object to describe it location in the Second Life.
One of two coodinate system could be used: Following name of relevant API classes from Second Life WebMap API we will call them XYPoint and SLPoint.

SLPoint coordinate system uses (Region, X,Y,Z) 4-tuple, where Region is Second Life Region name (case insensitive, lower case us recommended), and x,y,z is coordinates within this region. This coordinate system is also used by SLurls.

slgeo:region - Name of Second Life region. Case insensitive, lower case us recommended
slgeo:x - x coordinate within the region
slgeo:y - y coordinate within the region
slgeo:z - z coordinate within the region

Alternatively, XYPoint coordinate system is using global two-dimensional coordinates to specify location with second life. Use this application to find XYPoint coordinates of any location within the game.

slxygeo:x - x coordinate within the game
slxygeo:y - y coordinate within the game

Either system could be used, but SLPoint is recommended, since it could be easier converted to SLURL and these coordinates are easily obtainable from within the game. It also specify more precise location, including 'z' coordinate.

Additionally regardless of the coordinate system used, special tag 'slgeotagged' should be included to distinguish objects geotagged in Second Life.

SLPoint example:


XYPoint example:


You can attach these tags to images at Flickr, Imageshack, or videos at YouTube.

You can also specify these tags for you blog posts at blogger or other blogging systems. Here is simple tool which will help you to generate geo tagging fragment for your blog posts. To display locations mentioned in some blog use this tool.

Related tags: , , :[,,,]


kosso said...

Excellent ideas Lev! I think the timing is perfect to have this RFC to determine a simple notation for GPSL positioning ;)

kosso said...
This comment has been removed by a blog administrator.
kosso said...


OK. I was about to implement a namespace while looking at this and coming up with some ideas.

I think the elements slgeox, slgeoy, slxygeox, slxygeoy, etc might be a bit confusing.

I suggest creating the namespace sl: and having these elements:

for coordinates relative to a sim


for global coordinates


sl:mature - Boolean value

sl:avatar - The name of the avatar

What do you think? ;)

Lev Kamenev said...

In my proposal I was following existing geotgagging practice used by Flickr, which they in turn borrowed from Plazer.

Instead of adding special RSS elements with their own namepsace, they use 'tags' to encode spatial information. This approach is backward compatible with many other existing applications which works with tags.

The drawback of this approach is that there is no namespace and tag encodes both name and value information. I have followed Fickr approach and used column to separate name and value within tag.

kosso said...

hi lev

Where can a see a Yahoo rss feed with geotags?

Also, have a quick look at an rss feed from bloghud.com, where I am testing my implementation

I think an SL namespace would be beneficial for all sorts of things - including sl geotagging