PDA

View Full Version : Moving a large number of points



scott.epp
2010-09-07, 03:25 PM
I have 20 some lidar files with over 70 thou. points in each.. I need to find a way to correct an error in them. They must move a small amount in N,E, and Z direction. Anyone have any idea's ...

I have tried.

Inserting them into excel but am limited to 69 TH points... I could do it this way but some files have over 1.3 M points. I would have to create way to many smaller groupings for each and introduce many errors.

Inserting them into CAD and selecting sections at a time but it crashes.
Does anyone know if CAD is limited to selecting a certain number of entities or should this be able to work?

I have thought about limiting the sample number of points but would like to use every point if possible.

sinc
2010-09-07, 03:48 PM
C3D 2009 in particular has a tendency to crash if you select a lot of Cogo Points while the Properties palette is open. C3D 2010 is better in this regard, but still has some issues. You might be able to do what you want if you make sure the Properties palette is closed first.

But moving Cogo Points also seems to be slow in many versions of Civil 3D, for some bizarre reason... There's a MOVEPOINTS command in the Free Edition of the Sincpac-C3D (http://www.quuxsoft.com) that moves them much faster.

You might be better-off, though, by going with a completely different approach... You can create a Surface by adding the Point File directly to the surface definition, without creating Cogo Points. This results in MUCH better performance inside of C3D. Once you create the surface, you should be able to move the entire surface as one giant object. That might work the best.

david.zavislan
2010-09-08, 03:26 PM
For bulk data conversion like this, we use Safe Software's FME program.

http://www.safe.com/products/desktop/overview.php

Coolmo
2010-09-10, 01:18 AM
When importing X,Y,Z files for use in a surface, isn't there a way to adjust the coordinates of each on import? I think it's in the dialog box when you select the file and point format.

On the other hand, you could simply build the surface from the points and then move it around via the software.

Coolmo
2010-09-10, 01:26 AM
I will say this though. We use LIDAR Bare Earth Data all the time and I've never been able to import more than 4 files without a crash... and those were the older files when they use to actually process them before they uploaded them. All the files now-a-days seem to be 10 times the size (i.e. 10 times the points) for the same panel size. I got fed up with this and wrote a program that lets you select a box to find points in and it goes through each selected file and searches for points that fall within the box and then writes a new, smaller X,Y,Z file for the surface build.