CloudCompare forum

Hi!

I have multiple clouds, scanned at different times of a tunnel excavated.
At the end of the excavation, I import the clouds and combine them.
When combining, since scans are done when excavating, the scans contain several tunnel faces.

Is there a way to delete all internal points and keep the points on the perimeter of the tunnel?

Well, it depends on the shape of the tunnel (straight or curved?) and whether the final cloud has a high density or not.

If it's straight, then you can use the scissors tool to remove most the points inside (by looking at the tunnel in the right orientation).

Else, or if the cloud is dense, then you can compute the 'PCV' illumination scalar field (with the plugin of the same name). Use the 360° option. Then you'll get an illumination scalar field, that should help you remove the 'darkest' points (with 'Edit > Scalar fields > Filter by value').