cad3d converting problems

[Olly Betts]

On Tue, May 14, 2002 at 06:31:15PM +0200, Roger Schuster wrote:
> Because I used Compass (a surveying software from the U.S.)  in the last 
> years I first was interested in the capabilities of the -P option which 
> converts *.3d files to *.plt (the native file format of the Compass Cave 
> Viewer).

The conversion is fairly crude at present - it's really there so you can export
data for use with Carto.  For example, all the data is put into a single survey
as far as Compass is concerend.

> A smaller cave (~1000 m, ~60 stations) from my own data was 
> converted without problems. The *.plt file looks in Cave Viewer the same as 
> the *.3d file in Aven. The all.3d from the Survex sample data was a bigger 
> problem. The elevation looks in Compass nearly the same as in Aven but the 
> plan view in Compass is very distorted. You can see the survey crossed by 
> vertical lines - looks like a cave map with a bar code printed on it. :-)

It sounds like the coordinates are being wrapped round into a smaller range.

It's notable that the austria data uses coordinates in the map grid, so they're
quite large.

Does the converted .PLT file load into aven and display correctly?  That works
for me, so perhaps Compass doesn't expect such large coordinates, and is
wrapping them.  The coordinates are 6 digits in feet (the largest is
234822.900).  Let me know if you can load the .PLT file into aven, and if so
I'll ask Larry about this.

> The DXF export of large caves from the Austrian data seems to be 
> problematic, too. Corel Draw 9 crashed if I imported all.dxf.

I've not had reports of any trouble in the past, and I can import all.dxf into
QCad, which is the first DXF capable CAD package for Linux I found.  I'll try
some others when I have more time, but if Corel Draw crashes, rather than
politely complaining, I'd tend to suspect it's failing to cope with the file
for some reason; perhaps size - it is 2.3Mb (DXF is very verbose).

Cheers,
Olly