RE: DEM to VRML

["Crispen, Bob" <Robert.Crispen@HSV.Boeing.com>]

Martin Reddy sez:

> > I'm currently working on a utility to turn DEM files into VRML
> elevation
> > grids, anyone interested in this?
> 
> Bob Crispin has written just such a utility. You can download this
> from his
> free software page (look for the dem2wrl.zip link):
> 
>    http://hiwaay.net/~crispen/src
> 
Boy, you've got to be quick around here.  I was
fixin' to say that.  Thanks.

That little tool is there and available, but I need to
point out some of its limitations:

(a) It only works with USGS DEMs of the (I believe)
1:250,000 scale.

(b) It uses no algorithm at all for interpolating if
you set the option to choose every N points
from the DEM file (a darn good idea, btw).  It
simply picks every Nth point.

(c) It has no way of dividing the grid into pieces,
which is also a good idea.

Since I started with John Larimer's excellent
dem2tga program, I have no pride of ownership
at all, and would be delighted to have someone
else put their name at the top of the code and
carry on from there.  The zip file contains the C
source code (vanilla Unix-style C) and a Win95
executable that runs in a DOS shell.

If anyone would like to hack on it who doesn't
have a C compiler for the Windows platform, I'll
be happy to run it through gcc on my machine
whenever you like.

I figure I've taken it about as far as someone with
my abysmal knowledge of geo data can take it,
and would welcome someone else taking it
over.

Bob Crispen
bob.crispen@boeing.com