clean points in a tunnel / e57 geoslam scanner

[kageralex]

Hi

i have a question. i would like to clean objects in a tunnel.
for example object.jpg.

i now made a cross section and i am now able to cut out the building.

but afterwards i want to make a mesh over the complete tunnel. but i now just can cut out the building in the cross section.

is there a way i can cut out this building without a cross section ?

[daniel]

What does the cloud in your snapshot look like from behind? Do you see the 'ground' or do you see the empty building from behind?

If it's more like a closed shell, then you can use the 'PCV' plugin to compute the 'illumination' of points (see https://www.cloudcompare.org/doc/wiki/i ... s_(plugin)). This will give you a scalar field that you can use to filter out the darkest points (= the points inside the tunnel).