Import surface with LandXML

[Gordon Reynolds]

Allen,
Try a different approach.
1. Make sure that the drawing, and project , where you created the surface
has the correct coordinate system set.
2. Start a new drawing in the project in the safe project from step 1
a. Set the coordinate zone to the new zone that you desire
b. You should be able to access points, surfaces, alignments etc and
have the coordinates convert automatically

"Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message
news:4BD7A19FF7378A23...@in.WebX.maYIadrTaRb...
> I've created a Surface in Land 3 in our current State Plane Coordinate
> System. I want to convert this to the previous (NAD 27) system. I thought
> the way to do this would be to export the surface to a LandXML file and
> Import it to a drawing with the NAD 27 zone set. This is a large surface
and
> the resulting file is 92.8MB. I have tried 3 times to import this surface.
I
> get as far as the LandXML import dialog box. At that point it says "
> Preparing the Import file and comparing the Project data. Please wait..."
> This is as far as I can get. This third time I have let it run for over an
> hour and a half with no visible progress. Task Manager shows 50% CPU
usage,
> which with a dual processor means I've pegged one processor with little
use
> of the other, and some paging in the physical memory.
>
> Am I barking up the wrong tree? Am I doing something wrong? Is there
another
> way to accomplish this?
>
> My System
> HP Visualize P-Class Workstation
> Dual 1.2 GHz PIII Processors
> 512 MB RAM
> Windows NT 4.0 SP6
> ELSA Gloria II 64MB
>
> Thanks:
> Allen
>
>

[Allen S. Jessup]

[Neil Wilson]

You seem to be doing things properly. I would suggest you try a test run
using a partial dataset from your surface data and see if it works. The
large dataset may be be the problem, or there may some anomaly in the data
that is causing a hang. I don't have experience with transforming project
data ussing XML, but I have tried using it to share DTM with a Microstation
user without success. I suspect the XML format has some reliability issues.

"Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message
news:4BD7A19FF7378A23...@in.WebX.maYIadrTaRb...

[Allen S. Jessup]

It's been running over 2.5 hours now and I think I see some movement in the
progress bar. It may be working but it looks like it will take about 10
hours or more. I think my best bet is to kill it for now and try some other
approaches. I'd probably be able to query 3D lines or faces in Map much
faster. Then I'll try to set this up to run overnight.

Allen

"Neil Wilson" <nei...@ci.devils-lake.nd.us> wrote in message
news:073EF76C50D54356...@in.WebX.maYIadrTaRb...

[David Renaud]

Are you networked? Try it from the C drive.

D

[Steve Cannon]

Hi Allen,

The basic drawback to LandXML, is that AutoDesk chose to implement the
feature as a VBA application, utilizing the Land API. The problem with VBA
code is that it is not compiled, and this limitation adversely affects
processing speed. Anybody that has worked with he Land API also should be
aware of its extremely slow processing speed. A much better LandXML
implementation would have been compiled code that interfaces directly with
the binary data structure, instead of relying on the very slow Land API.

Your are seeing the result - the inability of LandXML to manage large data
sets in realistic time frames. Give it time, and it will eventually finish.
I recently imported a 30 meg LandXML file - it took 6 hours on a Athalon
1.4. Also, be aware that after the message "Preparing the Import file and
comparing the Project data. Please wait...", you will still are going to get
another dialog with which you must interface - and you are not even half-way
to the end.

I DO see this as a real impediment to the ability of the user to depend on
LandXML was a workable solution. I am afraid that with the time AutoDesk
has put into the existing LandXML code, you are not going to see them tear
it down and start-over any time soon. A complete re-write with a whole new
approach is really what is needed.

sc

"Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message
news:4BD7A19FF7378A23...@in.WebX.maYIadrTaRb...

[Glen Albert]

That's a fairly large surface file. Try setting the import option for
surfaces to "quick".

"Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message
news:4BD7A19FF7378A23...@in.WebX.maYIadrTaRb...

[Steve Cannon]

Glen,

But then you lose the triangulation... You might as well be working with an
ascii point file.

sc

"Glen Albert" <glen....@autodes.com> wrote in message
news:3515A183F5445DDE...@in.WebX.maYIadrTaRb...

[Allen S. Jessup]

Thanks for the info Steve. I've already aborted the import. I was going to
try to run it overnight but if it will need user input that will not help.
I'm going to insert 3D lines in the original drawing and query them into the
new one. Then I'll build the new surface from there.

Allen

"Steve Cannon" <lt...@swcp.com> wrote in message
news:D6AA8C70FFA2A534...@in.WebX.maYIadrTaRb...

[Allen S. Jessup]

I'm on the hard drive.

"David Renaud" <dre...@reiengineering.com> wrote in message
news:3E53B1A1...@reiengineering.com...

[Allen S. Jessup]

FYI

Fist try on Querying 3D lines resulted in a Blue Screen of Death!
Second try resulted in an error, after 45 minutes,
"Unpredictable error - Access violation
Line 1207 in file F:\F025prod\ade\source\dwg\mapDwgDatabase.ccp"
My F drive is an empty CD reader??

"Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message

news:639BA909CE572DCF...@in.WebX.maYIadrTaRb...

[Neil Wilson]

I would first do a full shut down and restart. You likely went unstable
after aborting the XML import. Next, I would partition your query by
location and see if there is a certain area of the DTM that is causing a
problem.

"Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message

news:4A2F270142614319...@in.WebX.maYIadrTaRb...

[Allen S. Jessup]

I'm doing so now. I'm also going to limit the query to certain areas that I
am interested in. It would have been nice to have the whole area transformed
but this is taking too much time.

Thanks
Allen

"Neil Wilson" <nei...@ci.devils-lake.nd.us> wrote in message

news:18E123B027371C0F...@in.WebX.maYIadrTaRb...

[Allen S. Jessup]

I managed to query a smaller area. That will do me for now. Just a little
disappointed that I couldn't get it all.

Allen

"Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message

news:A45250EAEB842DBE...@in.WebX.maYIadrTaRb...

[Neil Wilson]

Been there.

"Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message

news:A60350007380C2B8...@in.WebX.maYIadrTaRb...

[Gordon Reynolds]

Sorry I jumped the gun,
You can use MAP to do coordinate conversions. Make your TIN an import the
3d lines. Make sure the drawing has the coordinate system defiend. Start a
new drawing defining with the final coordinate system that you desire.
Under the project workspace attach the drawing with the original surface.
Right click on the drawing and quick view - zoom to 3d line. Define a query
using location and query mode as draw. The 3d lines will be imported to the
current coordinate systems and you can create a new surface using the 3d
lines.

"Gordon Reynolds" <cad...@rtsinc.net> wrote in message
news:28E5019D49D1845D...@in.WebX.maYIadrTaRb...

[Allen S. Jessup]

Yes I've done this. However!! It does not look, at this time, that the
conversion included elevations.

I'm looking into this now. At the moment I'm getting identical elevations in
the drawing I queried the 3D lines into. The elevation should be aprox.
0.86' higher in this system. I well be greatly perturbed if I find that the
conversions are only 2D!

Allen

"Gordon Reynolds" <cad...@rtsinc.net> wrote in message

news:A286EF5F5B40DC70...@in.WebX.maYIadrTaRb...

[Allen S. Jessup]

Wow! That's scary. I wonder how may people have missed that. Thanks for
confirming this. I thought I'd probably done something wrong.

This could cause problems over a large area. I know that the shift over the
area I'm working in, the small area not the whole 28 sq. mi., the shift is
NOT constant.

If I ever get the LandXML to work I hope this will handle that ever
important 3rd dimension.

"Neil Wilson" <nei...@ci.devils-lake.nd.us> wrote in message

news:A889026EBD2863A9...@in.WebX.maYIadrTaRb...
> Map projection transformations are 2D. If you need to change vertical
> Datums, you will have to determine the difference in elevation between yur
> datums for your location and apply a datum shift.

>
> "Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message

> news:F2C98963AAF21DB7...@in.WebX.maYIadrTaRb...

[Neil Wilson]

Map projection transformations are 2D. If you need to change vertical
Datums, you will have to determine the difference in elevation between yur
datums for your location and apply a datum shift.

"Allen S. Jessup" <jes...@co.rockland.ny.us> wrote in message
news:F2C98963AAF21DB7...@in.WebX.maYIadrTaRb...