How does align tool work ?

[Jean-Yves]

Hello,
I'm looking for documentation to understand how the “align” tool works.
On which values is the root mean square calculated?
How does it work?

Thank you in advance.

[daniel]

So the documentation is here: https://www.cloudcompare.org/doc/wiki/index.php/Align

And the RMS is simply the root of the average squared distance between every pair of points (after registration).