CloudCompare forum

Posted: **Wed Mar 04, 2026 2:55 pm**

Hi, I been using the program to work with cloud points of a tunnel excavation and creating a mesh with Poisson recon, the problem is no matter what configuration I use to compute the normals they always turn to be blacks dots on the cloud. Also the cloud is not in an singular axis, but planar is the best option for the tipe of surface I'm working on. I can create the mesh anyway, so I don't know how this might be affecting the mesh creation process.
I put images of how the cloud point looks.

: The cloud of the front of the tunnel excavation; Captura de pantalla 2026-03-04 113733.png (1.3 MiB) Viewed 4282 times

: Computed normals in the front; Captura de pantalla 2026-03-04 113401.png (188.2 KiB) Viewed 4282 times

: Computed normals in the back; Captura de pantalla 2026-03-04 114011.png (43.14 KiB) Viewed 4282 times

: Mesh whit RGB colors; Captura de pantalla 2026-03-04 115345.png (2 MiB) Viewed 4282 times

Posted: **Fri Mar 06, 2026 2:39 pm**

For the 2nd and 3rd images: aren't the normal simply inverted? That would explain why you have a clean model in the end.

And have you tried the Minimum Spanning Tree algorithm to (try to) set the orientations in a more dynamic way?

CloudCompare forum

Problem to compute normals

Problem to compute normals

Re: Problem to compute normals