How to find centreline of point cloud tree scan

[Jenna3 (Jenna)]

Hi all, I’ve been given point cloud scans of trees and I need to draw their centrelines.

Usually I just do this by hand in Rhino, but was wondering if it would be possible to automate this in Rhino/Grasshopper instead.

I’ve attached the Rhino file with the point cloud below. This is what it looks like:

Thanks in advance!

point cloud - tree.3dm (12.2 MB)

[laurent_delrieu]

Hello
you could look at that.

Cockroach - PointCloud Processing for Rhino

A new Cockroach version for Grasshopper has been released and uploaded on Food4Rhino. The plugin is compiled for Windows Rhino 6 and 7. This time we also open-source the full code of Cockroach, which employs three libraries: Open3D, CGAL, Cilantro. All of the C++ libraries are correctly cited and follows necessary license agreements. The Cockroach plugin provides wrappers for the .NET via PInvoke. GitHub - 9and3/Cockroach: A plug-in for Rhino point cloud post-processing and meshing The goal …

Mesh Skeleton

Dear @laurent_delrieu I would like to ask about this old script of yours about mesh curve offset: I found its use by computing medial axis similar to this post: Do you think there is a faster method to compute curve offset or somehow optimize your script? Currently it takes a few seconds to compute:) Any ideas would be very helpful. Also maybe you C# version instead of VB? [MedialAxis] MedialAxis.gh (44.1 KB) [MedialAxisField]

[brvdln (Brv)]

this could be a way.
I started from a surface, but you should reconstruct the surface from the point cloud
Area_contorno.gh (89.8 KB)

[cdordoni]

Here is a related thread

Extract center curves from 3D meshes

I’m looking for a way to extract the skeleton of a mesh - the center curves of the solid mesh. I have previously used ngon mesh skeleton component, but in the latest version this component is no longer there. (@Petras_Vestartas). Are there any alternatives? Or suggestions for methods. This article describes pretty well what I intend to do Image from article: [image]

[Eef_Weenink]

Just basic components do the job fine:

• selected all points
• 3D convex hull
• bounding box (to find a diagonal line close to center)
• contours of convex hull (what is a mesh)
• area to find center(s)
• interpolate to create curve
• extend a bit to have all cloud
  
  
  
  
  
  
  center of point cloud tree scan.gh (322.8 KB)

[René_Corella]

Hi, NOT saying at all this is “the” automated answer, but I thought it could be fun.

1. Divide the “Z” values of your points into domain sections:
   

   

2. Get the ‘average’ point of each one of these point groups (you could also use the bounding box centers) and connect them:
   

   

3. You could also fit a line through the original points to create a new plane whose Z vector is the line itself and use that as your “more local” coordinate system for the “Z’s” of your points:

polyline-through-pts.gh (349.5 KB)