CGAL users discussion list

[Nick Alger <>]

Hi. I have never used CGAL before, and I am trying to determine if it is appropriate for the task I'm working on, or whether I should look for another library.

I have a nonconvex nonuniform triangulation in 2D that comes from a finite element discretization, and I want to use an AABB tree to perform geometric queries. (e.g., What triangle is a point in? What is the closest point in the triangulation? etc...)

I see that CGAL can make AABB trees for 3D, but not 2D. I can use the 3D AABB tree by taking my 2D points, and making them 3D by setting the z coordinate equal to zero. Is this an advisable hack? Will the CGAL AABB tree algorithm still perform well when the triangles are all on the same plane and infinitely thin?

Also, where I can find more details on the algorithm that CGAL uses for constructing AABB trees? I know about AABB trees in general; I am looking for specifics. How does CGAL choose which boxes to group when building the hierarchy, etc..?

Thanks for any help!