Creating 3d Terrain
Ash
I am a final year engineering student, and for my final project I have
too create 3D visuals of actual terrian. Incorporating DEM of the UK.
Now, I have looked into DEM data, but its hard too get hold of UK DEM,
and then, once I have this, how do I even go about beginning to input
the DEM into a program. I dont have much VRML experiance, however I do
have a sample program, which creates fake 3D terrain, I was wondering,
can I just change the coordinates in this program with that of the
DEM????
shane
Do a search on dem to vrml converter.
Google responds with a slew of them.
If you have a few $, there are some great
tools available such as Leveller and 3DEM.
Dems are usually huge files. To use them
in vrml you have to extract a selection.
The tools I mentioned will do that.
Doing it in a text editor will result in a
stay in the looney bin.
s.
"Ash" <ahsanu...@kcl.ac.uk> wrote in message
news:5dd72aec.02033...@posting.google.com...
Wayne Hogue
AccuTrans 3D available at http://www.micromouse.ca/
will convert USGS DEM, GTOPO30 and DEM/SDTS to VRML files.
Wayne Hogue
MicroMouse Productions
dcode
dcode
umm, no you can't, sorry, my mistake, you can get dted data, which is pretty
much the same as dem
Garry Keltie
will get you 1km / pixel elevation data (signed 16 bit integer MSB)
This can be an ESRI BIL file if you tweak the .hdr file (its not really
a usgs dem file), it can also be an ER Mapper BIL file if you import it
as binary BIL (change the .dem file to a .bil) or get the .ers headers
from www.ermapper.com. A subset of this will give you a reasonably
compact elevation dataset for the UK.
All the talk of dem is not going to help you get any data of the UK into
'one' of the usgs dem formats, there are very few tools that will take
on such a task (such as ERDAS imagine). You get an idea how US-o'centric
geo tools (OTS) are as many will read the dem formats the usgs produce
but little will write them. To obtain usgs like dems for outside the US
you may have to go the us defence format: dted, again, a dog of a format
and unless you know anyone in the MOD, its unlikely you'll get very
resolved data at all for the UK.
http://earthobservatory.nasa.gov/Newsroom/BlueMarble/
will get you 1km /pixel imagery (24 bit RGB) Comes as two rather large
tiffs, ask your geomatics department if they have them already to save
the download. Again, a subset of this (while nowhere as nice as Landsat)
will give you a compact coverage.
You might want to try TerraVision? www.tvgeo.com, SRI, who also (mostly)
bring us GeoVRML, provide tools for generating tiled pyramids of
elevation and texture images. You can use the TerraVision browser or
export to GeoVRML with their tsm tools. The Gtopo data can be imported
as single band raw image data, the tiff as a tiff or ppm. There is a
little problem with it however in getting down to the fullest resolution
of the elevation data depending on your ratio of texture:elevation
resolution. Ideally 30m /pixel landsat coverage draped over the 1km
Gtopo30 elevation data will give you optimum results. If you can source
that amount (or even subset over nominated areas) of Landsat imagery
you'll be in.
Cheers
Garry
--
Garry Keltie
garry....@rmit.edu.au
Interactive Information Institute &
School of Architecture and Design
RMIT
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