From: Andrew Preece (apreece++at++reading.sgi.com)
Date: 03/21/2000 02:35:51
Hi Detlev,
DFAD is a really nasty format to read as opposed to DTED which
is really simple to read. As a result there are quite a few
copies of DTED readers around and a number of them for free
and very few DFAD readers (that are free src code).
The other problem is that the data in DFAD is all cultural
data stored in 2D (just XY (lat/long) data) so there is a
significant amount of extra processing that you have to do to
the data once you have read it in to use it in a 3D database,
such as cutting the Areal features into the terrain skin,
layering the Linear features (roads etc) over the terrain etc.
Of course the data is perfect for use as a overlay in 2D for
a mapping system, for example.
Your best bet, if you have some spare cash, is to buy a DFAD
integration tool like (in no particular order):
1. EasyTerrain from Centric software:
http://www.centricsoftware.com/41series/
2. TerrainPro option in Creator from MPI (Multigen Paradigm):
http://www.multigen-paradigm.com/.
3. Terra Vista from Terrex: http://www.terrex.com/
4. TerraTools from TerraSim: http://www.terrasim.com/
5. ArcInfo from ESRI: http://www.esri.com/
6. Imagine from ERDAS: http://www.erdas.com/
7. Hummingbird: http://www.hummingbirdcomp.com/translation.htm
8. TerrainView: http://www.viewtec.ch/terrainviewservices_e.html
The former US Defence Mapping Agency (now NIMA) owns the
DFAD format and is currently in the process of upgrading it
with a new format called Vector Product Format (VPF). You can
get source code for VPF by downloading their free NIMAMUSE tool
set from: http://164.214.2.59/geospatial/SW_TOOLS/NIMAMUSE/
This page: http://164.214.2.59/publications/specs/index.html
list all the current NIMA format specifications, which may
help you write your own.... or you could look at:
http://www.mtop.com/vrml/dfdlayout.html
There are also discussions on DFAD support in the Performer
archives that may be of help,
I hope this helps,
Andy.
-----Original Message-----
From: Detlev Offenbach [mailto:detlev++at++asterix.gallien.de]
Sent: 20 March 2000 7:37
To: info-performer++at++sgi.com
Subject: Importer for DFAD-data
Hello all,
I have the need to read some DFAD-data and build a texture for a terrain
built
from DTED. Is there a DFAD reader around with source code that I could
include
in my app?
--
Detlev Offenbach
detlev++at++offenbach.fs.uunet.de
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