Cloud and plane intersections

[dFx]

Hi,
from a 3D scan of a wood part, I would like to output some points only.
Ideally, I would cut my wood part in 10 consecutive sections over Y (which looks like a triangle), and then, 6 stacked sections over X.
I tryed using M3C2 but I'm affraid I'm not getting any expected result, by lack of understanding.

Expected output is points coordonates of every red points (not all drawn for easier representation).

Plane.png (4.16 KiB) Viewed 1792 times

Wood.png (82.61 KiB) Viewed 1792 times

Actually to succeed, i'm using cross section tool with repetition and gaps, and then subsampling. But it doesn't feel like the way to do it.

any help apreciated.

[daniel]

Hum, I'm not sure to see how M3C2 could have helped? (what is the other cloud you would use to compute the distances in this case?). Or wouldn't it be simpler to directly export the X and Y coordinates as scalar field if you want to use a SF to segment some points maybe?

I also see that you seem to be using a mesh, which makes things even more complex. You may want to convert it to a cloud (with 'Edit > Mesh > Subsample'), else if you need to keep a mesh, then the Cross Section tool is the only tool that can handle that properly.

[dFx]

Bonjour Daniel,
That's the whole point, I'm pretty new with 3D pointclouds and CloudCompare in general, so i'm looking for a way (tool ?) to achieve my goal.

I've saw a post from a user saying that using M3C2, he could gather intersections between two clouds, so that was my first intend.

Actually my data is generated as a scalar field, as it is from a 3D laser scanner. But I didn't manage to format it correctly, without using a temporary STL format, represented as a mesh in CC.
And the second issue I have, is my data is generated from two scans, with a 120° tilt angle (over Y) and a different Z offset. That leads to dataloss if I use a merged SF in XY plane, which is not wanted because of the features I later need to detect on scanned product.
So I'm trying to work with point clouds, even if sometimes it is easier to just display them as mesh.

[daniel]

Sorry, but I don't really understand how it can be simpler to generate a STL file from a laser scanner cloud :D (that's generally the opposite). Maybe you want to discuss that directly (in French) by sending an email to admin@cloudcompare.org. And if you can share data that may be useful also.