Output points of Delaunay Ttriangulation

Hello,

I'm studying a matlab code where a Delaunay Triangulation is performed. I want to understand in which order are the output points.

I tried with a simple example like this one:

X = [0; 2; 3; 4; 5]
Y = [4; 3; 1; 4; 2]
dt = DelaunayTri(X, Y);
dt.Triangulation

I receive this output:

1     2     4
2     1     3
2     3     4
4     3     5

But I don't understand the order. I tried to compute the circumcenter and to order the points related to the single triangle in anti-clockwise, but it did not work.

Could you help me?

[Sean de Wolski]

Why do you want to know, or I guess: What's the end goal?

[Andrea Pennisi]

Because It is important for next part of the code that is written by using mex and if I change the order of the points the output of the mex function is different.

[Sean de Wolski]

So the order has to be something specific for the MEX function but you can't change the order?

I'm confused. Are you able to reorder the triangles before passing it to the MEX function?

[Andrea Pennisi]

So I explain better. I'm making a porting of a matlab code in c++. I use CGAL library to compute the delaunay triangulation. The second step is to pass the result of the delaunay triangulation to a mex function that I properly modified to adapt it to my code. Now If I pass my output, that is the same of matlab but with a different point order (e.g. my output is 1 2 4, matlab output is 2 1 4) the output of the mex function depends by the order of the triangle vertices.