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Large Coordinates - Can't see full data

Posted: Tue May 05, 2020 4:13 pm
by bcbusseau
Before georeferencing my data, my point cloud was full (no data was missing). Now that it is georeferenced when I import it in, it has a lot of data missing. It shows in linear features. I read viewtopic.php?t=68, but it doesn't tell me how I can visualise my point cloud as before.

Re: Large Coordinates - Can't see full data

Posted: Wed May 06, 2020 8:32 pm
by daniel
Did you accept the Global Shift? (either at the time you applied the georeferencing transformation or at the time you imported it?). Otheriwse you'll have an accuracy issue that cause these stripes.

Re: Large Coordinates - Can't see full data

Posted: Thu May 07, 2020 7:24 am
by bcbusseau
Hi Daniel,
When I accept the global shift, then I can't export my file anymore. Once georeferenced and I try to save the new file I get a pdal exception: "pdal exception unable to convert scaled value". I can save it to a .las 1.3 or 1.4, but then I can't use it in pdal anymore.

Re: Large Coordinates - Can't see full data

Posted: Thu May 07, 2020 7:26 pm
by bcbusseau
This seems to be a bug. I downloaded Cloud Compare version 2.10 and all is good now.

Re: Large Coordinates - Can't see full data

Posted: Thu May 07, 2020 7:29 pm
by WargodHernandez
Which version gave you the error before?

Re: Large Coordinates - Can't see full data

Posted: Thu May 07, 2020 8:15 pm
by bcbusseau
I just don't understand how to apply the global shift back when exporting the las file

Re: Large Coordinates - Can't see full data

Posted: Fri May 08, 2020 7:10 am
by daniel
Normally this is done automatically (you don't have anything to do).

But I'm more interested by the bug you may have found: which version did you use to make it happen? And can you describe your exact process?

Re: Large Coordinates - Can't see full data

Posted: Thu May 14, 2020 5:49 pm
by bcbusseau
Hi Daniel,
I was using CLoud compare version 2.11.beta. But now switched to 2.10. Turns out it worked for a few days with 2.10 and now I'm gettign similar issues where I can't export.
Taking you through my steps:
1. importing a LAS file with no coordinate system to Cloud compare. I get a pop up then only for the specs of the data I want (Open LAS file window)
2. importing a point shapefile with z values in ESPG:26911. I get a global shift/scale pop up for this as the coordinate are too big. and I click Yes to All. and save this information. (shift: -465400.00, -5475900.00, 0.00, 1.000000)
3. I use the ALign two clouds by picking points where my Aligned layer is the non-georefeenced Las file and my reference layer is shapefile.
4. once done the data is aligned well together.
5. from here if I try to export directly to LAS cloud (*.las*.laz) , it used to work but doesn't anymore:
- the first time I used it was using v2.11.beta and the data exported with no issues and the shift was reapplied to the layer, an so the layer was good.
- few days later I was not able to export would get the error message "pdal exception unable to convert scaled value"
- I downloaded cloud compare 2.10.2 and got no error with the same work flow last week.
- Today with the same workflow in 2.10.2 I get 2 different errors:
- [10:47:31] PDAL exception 'writers.las: Invalid value '0' for argument 'minor_version'.'
- [10:47:51] An error occurred while saving 'file_name': the third-party library in charge of saving/loading the file has failed to perform the operation

Re: Large Coordinates - Can't see full data

Posted: Thu May 14, 2020 10:40 pm
by bcbusseau
Update:
I just applied the transformation outside of cloud compare using PDAL and re-imported it within cloud compare to apply the shift and that worked.
pipeline used in pdal to do transformation.
pipeline = """[
"2020-02-14_SAL-M.laz",
{
"type":"filters.transformation",
"matrix":"-0.208659797907 -0.977300822735 0.036663495004 91.470603942871 0.970175147057 -0.211576551199 -0.118302658200 93.251342773438 0.123374417424 0.010885005817 0.992300510406 891.1702270507810.000000000000 0.000000000000 0.000000000000 1.000000000000"
},
{
"type":"writers.las",
"filename":"test_2.las"
}
]"""