How to create triangulated surface using data points (x,y,z)

I have set of points in 3D (x,y,z) in Cartesian coordinates.

I would like create surface mesh (in terms of finite element modeling) of these points.

I tried using DelaunayTri, but that gives me tetrahedral and not triangles, which I want.

Thanks Prab

[inderjeet]

Hello Prabh, I have the same problem. If you had solution. Can you please discuss?

Answer 1

[Jan]

A look in the FileExchange is always a good idea:

• http://www.mathworks.com/matlabcentral/fileexchange/28851-alpha-shapes
• http://www.mathworks.com/matlabcentral/fileexchange/32725-fast-alpha-hulls-parfor-enabled
• http://www.mathworks.com/matlabcentral/fileexchange/6760-ashape-a-pedestrian-alpha-shape-extractor

[Prabhjot]

It look promising will try to use it.

Thank you

Prab

Answer 2

[Titus Edelhofer]

Hi Prab,

I think you are looking for the convex hull? So take a look at convhulln or convexHull (depending on your MATLAB version).

Titus

[Prabhjot]

Hi Titus,

I dont want to use the convex hull because I loose lot of geometricl information in building convex hull.

My data is points that define a breast and the shape is important for my work.

Thanks

Prab

Answer 3

[Titus Edelhofer]

Hi Prab,

O.K., I understand. Can you use two coordinates only? E.g. x and y only, build the (2D) triangulation and then plot/analyze the triangles in 3D? If this is not directly possible, you might have the chance to rotate all points by a rotation matrix and then use 2D triangulation.

Titus

[Prabhjot]

Hi Titus,

I am not sure how will I get the 3D triangulated surface from these. however, from the above post by Jan Simon 7, its seems I can use the existing programs from Fileexchange and solve my current problem.

Thank you

Prab