Data sharing and visualisation

[Wookey]

On 2007-01-26 10:08 -0000, Andrew Brooks wrote:
> Hello
> 
> Some elementary questions from a new member!
> 
> 1. The BCRA Sig web page looks rather outdated so I'm not sure if there's any activity these days... Is this the right place to ask?!

There is actvity, but admitedly not on the web-page. That's nominally
my fault but anyone wanting to volunteer as webmaster could hardly do
a worse job.

There will be a fiedl meet in the spring in derbyshire the same
weekend as the cave technology symposium, with an emphasis on digitla
instruments. 

> 2. Is there now a "standard" file format for cave survey data?  The latest buzzword these days is XML so I presume someone's come up with a schema. (Yes, I know the saying which begins "The nice things about standards is...")

In a word, no. Numerous people have tried to create one, but the idea
has not caught on. In practice the file formats of popular surveying software is
the closest thing to a lingue franca. e.g. compass, survex. This is
one reason peope don't change survey package very often. There was
rosetta-stal by Taco van ieperen which converted between some formats
(Windows only I think).

> 3. Is there a unique repository for cave survey data, where people
> could go for data on "most" caves, or do surveyors still keep their
> own stuff secret?

It varies. Some remain very secretive. Some put it all online. The are
proposals for a UK archive, originally for a physical archive by
Andrew Atkinson (http://www.chaos.org.uk/survex/cp/CP25/CP25.htm), and
more recently an online version suggested by Harry Pearman
(http://www.chaos.org.uk/survex/cp/CP25/CP25.htm). There is a mailing
list to discuss it on,
(http://wookware.org/cgi-bin/mailman/listinfo/cave-survey-archive) but
only Harry has actually done anything in the last 18 months, although
quite a few others think it is an idea with potential. As ever it
needs someone to actualy implement things. 

> 4. Has anyone considered visualisation in more common software?
> Obviously something like Survex is the most cave-specific, but next
> would be a 3-D program, the most generic being something like a VRML
> plugin in a web browser.

Yes. This has been considered. The main problem with most VRML viewers
is that they are diesgned for worlds, not arbitrary models, and thus
are a pain to use for cave surveys. Quite a few bits of software spit
out VRML: therion, compass, karst, tunnel(?) 

Some of the cave-specific viewers are very good. Check out Karst,
Compass, survex 1.1 and Therion 0.4's loch viewer. There are others
I'm sure. (Hmm, must update my software list for the last 5 year's
developments sometime...)

There are also other 3D viewers and things like zoomify which I have
seen used online (but not the results as it is only for Windows and
Mac so useless to me).

> But I've thought of something I would like to have even more: cave
> survey data in a format suitable for Google Earth.  One way to do it
> very simply would be a KML file where the passages were elevated above
> the ground. That would let you see where the passages go in relation
> to the above-ground satellite images, and would let you see the cave
> in 3-D. (I've seen this done for aircraft tracks so I assume it's
> possible to represent cave passages in a similar way).

Someone posted about this just yesterday on the therion list.

It would be very good to use the general map interface rather than
google's API specifically - then you can use it over openstreetmap,
or anyone else's mapping data too, and don't get stuck with
proprietary software (which google earth is). I've fogotten the name
of said interface right now...

> I think it would be great if there was a repository where people
> could go to get all the South Wales caves (for example) in one place,
> and in an easily usable file format like this.  I'd love to see
> Draenen and Easegill, for example, overlaid on Google Earth...

I'm sure you are not along in this thought - if you make it happen
then people will no doubt use it...

There is an online survey repository proof of concept which has
some derbyshire, mendip and yorkshire info in so far.
See http://www.cavesurveys.com/ detailed in http://www.chaos.org.uk/survex/cp/CP25/CP25.htm

There are reasonably complete repositories in some other countries, such as
Switzerland, I understand (those swiss surveyors are _really_
organised :-). 

Wookey
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