CloudCompare forum

I have a number of LAZ files that I want to align to control points I have, and there are physical targets (nails, paint marks, etc.) in the scans that I want to use for this.

I am currently importing the LAZ, and then importing a csv of the control, and then using the "Align *point pairs picking" tool. The problem is that this workflow is more for aligning 2 scans together, and not aligning a scan to the control points. I am able to pick the point from the laz, and then manually enter in the X, Y, Z location for the control, but it is a bit of a tedious process. Also, by csv file of points isn't visible when running the Align command (it disappears), so it isn't ideal.

Is there a better way to register a point cloud to known targets? Ideally if I could leverage the csv file of control points by selecting which control it is as the reference instead of manually keying in would be great, but doesn't seem to be the case.

Do the control points really disappear when you use them with the Align tool (as 'reference' I guess)? Or are they just too small? (in which case you can increase their size prior to launching the tool in the cloud properties, or you can use the interactor in the top-left part of the screen to enlarge all the points).

Ideally we would need to allow users to load a CSV file and populate the list of reference points automatically, that's in the TODO list, but no one has had the time to do it apparently...

Hi Daniel. As I have imported a CSV file of the points along with the LAZ, when I run the align to control on the LAZ the other layer of CSV data does seem to just disappear. They are visible prior, but disappear when I launch the tool and also aren't impacted by the interactor in the top-left either.

Having the reference point populate automatically and be able to select the corresponding point in the LAZ would be ideal for sure. Also, the ability to toggle which points to use on / off in the list would be helpful when trying to validate the adjustment. Currently it uses all the points in the list and you can only delete the point pair which isn't ideal to troubleshoot / validate.

I would fully support this one on the todo list!