Triangulate a non-convex point set

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Oliver
Oliver on 21 Nov 2013
Edited: Sean de Wolski on 15 Oct 2014
I have a set of points in 3D that define the surface of a non-convex object, I would like to generate some kind of triangulation of these points so as to plot this surface. Any ideas how I might do this?
The convex hull won't work, because my points are on the surface of a non-convex body. I'm aware that the problem of defining a non-convex hull is ill-posed and has no unique solution. One way to go is the alpha-shape, and there is a file on the FEX that does this, but I was wondering if there is another (better) way?
  9 Comments
Antonio
Antonio on 3 Mar 2014
Sorry, you're right, it works. But it's not perfect.
In my case, if I set a low radius, some areas are not shown in the triangulation. But if I set a higher radius, the non-convex edge is distorted.
You can check this problem using my previous attachment.
I hope you could help me a bit...
Sean de Wolski
Sean de Wolski on 15 Oct 2014
Antonio, the R2014b alpha shape provides the alpha spectrum so you can see all radii that affect the hull.

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Answers (1)

Sean de Wolski
Sean de Wolski on 15 Oct 2014
Edited: Sean de Wolski on 15 Oct 2014
As of MATLAB R2014b, there is now a 2d and 3d alphaShape tool built into MATLAB.

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