Hi Mike,
The interface is shown here. The program is Civil 3D R2007 specific and to
run it, you must have a drawing with at least on one alignment. Other data
in the drawing is simply ignored.
The user needs to know which columns the Easting and Northing data is held
in.
The program searches for non-integer characters in the first line of the
data file and presumes the first such character found is the data divider.
It then replaces the divider with a single space, so that all output files
are space separated with the same column data and column order as the
original file.
--
Laurie Comerford
CADApps
www.cadapps.com.au
"Mike Norton"
wrote in message
news:5259095@discussion.autodesk.com...
You've got my attention, Laurie. The program sounds ideal for my LIDAR and
SONAR shoots. My pipeline guys rarely need surface data beyond a relatively
narrow swath.
I work with a group here shooting point clouds to create as-built drawings
for offshore facilities to facilitate new construction. Do the point clouds
you mention include co-planar points.
--
Mike Norton
Total CAD Systems, Inc. - Houston, Texas
"Laurie Comerford" wrote in message
news:5258556@discussion.autodesk.com...
Hi Mike,
We are currently quality control testing a program to filter a Point Cloud
based on an offset from an alignment.
At its simplest level of operation it will create one new file with all
points within a user nominated corridor half width.
At its most complex level of operation it will copy the original data file
into 31 segments:
Points not opposite the alignment
10 chainage ranges left of the user nominated corridor half width
10 chainage ranges right of the user nominated corridor half width
10 chainage ranges within of the user nominated corridor half width
This should allow the user only to work with relevant data.
The program should be ready for release to www.civil3Dtools.com within a
week or so.
By working logically you should be able to create data sets which are
relevant to a specific area.
We have run the program on 2,800,000 points over a 140km alignment (time
under 10 min on a midrange computer)
It is currently with a client who has a 30,000,000 point cloud and I'm
awaiting his report.
While under development I used a 100,000 point cloud which was processed in
18 seconds.
The program does not lose any data. We are considering an algorithm for a
"lossy" process which would create DTM suitable for site planning - as
distinct from design where the output of the current program should be used.
The sort of thing I have in mind is to throw the data into a data base and
use SQL queries to extract cells of information and compute the centroid for
each data set.
I would not expect any real development in that field for several months due
to other commitments as CADApps.
--
Laurie Comerford
CADApps
www.cadapps.com.au
"Mike Norton" wrote in message
news:5258321@discussion.autodesk.com...
My math may be a bit off but assuming they shot a 500' swath we're talking
about less than a million points here. I didn't think the ceiling was that
low.
Maybe my machine just isn't up to the task (Dell Precision M70, 2.3 ghz, 2.0
gb RAM) but I just attempted to build a surface from 2' contours (39,000+)
and crashed in just under 40 seconds. (I think with a bit more processor
speed I can get it down to under 30.) Nothing else was running and I even
disabled all options for minimizing flat areas.
Don't get me wrong - I'm not at all really interested in who can come up
with the most extreme dataset but this is a definite problem in the
petroleum industry and increasingly becoming a problem with advancing
"normal" survey technology. Can you share with us the prognosis (if any) for
future releases and/or service packs?
--
Mike Norton
Total CAD Systems, Inc. - Houston, Texas
"Anthony Governanti" wrote in message
news:5257672@discussion.autodesk.com...
Ok folks, I got the LIDAR point file from "akbowbender" and was able to get
it to work pretty well. its a 55 MB text file of XYZ coordinates. here is
what I recommended:
Ok, so I was able to work with the surface and get an alignment and profile
generated.
Here are some best practice suggestions when working with large amounts of
data:
1.. Use the Point File option for building the surface
1.. Create a new surface in a new drawing
2.. Use a Styl
e that just displays the Border (no contours or triangles)
3.. Expand the surface definition, then right click on the Point File
collection
4.. Choose Add.
5.. Select the appropriate file format (if there isn't one that matches
you can define one) - in this case, I used ENZ (XYZ) space delimited
6.. Browse and select the point file
7.. Select OK
2.. Once the surface is built (this took ~10 minutes on my machine) zoom
extents an
d save the file
3.. Optional step - close Civil 3D to clear out the memory on the system,
then reopen that drawing.
4.. Change to a style that displays you Contours - I used both 25'/125'
and 5'/25; intervals, and was able to get the display to come up in about 30
seconds
5.. Create your alignment
6.. Sample for your profile
7.. Create a Profile View - use a style for the profile view that has the
Minor grids turned
off, and doesn't Clip the grids to the profile. Clipping
takes up some memory, and will cause a delay, and sometime a lock up if the
system runs out of physical memory.
I was able to get a working drawing with these steps. Now we can further
improve performance by taking advantage of the Projects and data
referencing, but for now, I think this should help.
I've attached two screen shots - one of the contours at 5'/25' interval; and
one on th
e profile - Alignment length is 97,977 feet! Drawing size is 121
MB, but it opens it less the 30 seconds.
AG
"Anthony Governanti" wrote in message
news:5255646@discussion.autodesk.com...
I want to test this for myself. Can you send me a text file of the points
gridded at 15'?
anthony dot governanti at autodesk dot com
AG
wrote in message news:5253912@discussion.autodesk.com...
I have a LDT project for 65 miles of new road. Th
e terrain models are from
LIDAR gridded to 15'. The largest tin file is just over 300mb. Can C3D
handle this size file?
Autodesk seems to be hanging it's hat on C3D, so I guess I can't expect much
improvement in stability or new features in LDT. It can handle the large
surface files, but it does have stability problems at times. If C3D can
handle large surfaces, I may give it another try.
