[geovrml] adding vrml geometry to geovrml scenes

[Garry Keltie <garry.keltie@rmit.edu.au>]

Hi List,

Im trying to add some geometry which is located with utm coords
(x=eastings y=elevation z=-northings) to a geovrml scene. 

I understand the geovrml scene to be oriented to reflect its "round
earth" position on the globe, in geocentric coordinates. If I want to
use the regular vrml browser fly and walk navigation I should
(expensively) use the GeoOrigin's rotateYUp field.

There are a few things Im curious about though:

If I build a geovrml scene from tsmApi that is built to utm (using the
distributed utilities), do I get a flat representation that has some
"mean" point as a sort of normal for the orientation of the scene? or,
does it somehow curve to a round earth representation? (precalculated or
at runtime).

>From the above, if it is an oriented flat representation then would it
be easy to calculate that orientation and use a simple transform at the
top level to avoid the rotateYUp?

I tried building the tree with the make_geovrml "-utm" argument for an
explicitly flat representation, it did build although crashes the
browser on load. Im aware that its not an advertised argument but apears
in the tsmParseVRMLArgs function. Do I need to play with the api to
implement this option?

Failing all of that, is to geovrmlise a standard vrml scene (basically
building volumes that are georeferenced by their coordinates in a known
zone) my option? then , is there an an easy geovrml wrapper I can add to
it?

Cheers

--
Garry Keltie

garry.keltie@rmit.edu.au
InteractiveInformationInstitute &
School of Architecture and Design
RMIT