error in cloud 2 mesh distance sign

[jameshlally]

Hi, I'm a fairly new user using Cloudcompare specifically for the cloud to mesh function. i have a set of xyz points for which i want to evaluate the distance to closed ('solid') meshes generated in 3D geology modelling software. The distance needs to be signed correctly to distinguish 'inside' from 'outside' points relative to the solid. Cloud 2 mesh works mostly fine for this with negative outside and positive inside, but then i get a few seemingly random points that change sign even though they are all 'oustide' the closed mesh (see attached screen shots for an example). Any idea what might be causing this behaviour?

cheers

James

[daniel]

Well, it can happen in some weird cases sadly. Especially if the local topology of the mesh is funky (i.e. some twisted / flipped triangles, etc.). But it may be also very limit cases when the point is as close to two triangles that face backwards.

Can you maybe send me your dataset for me to test on my side? (admin [at] cloudcompare.org)