CGAL users discussion list

[Hugo Mercier <>]

Hi all,

I am trying to figure out how to test the intersection (and retrieve the 
result of intersection as a second step) between some primitives and a 
Nef_polyhedron_3.

If I want to test the intersection with a >=2-dimension primitive, I 
think a good way is to build a Polyhedron_3 from that primitive and 
substract it from the Nef_polyhedron.

But what about points and lines ?

About points, there is a locate( Point_3 ) method, but I cannot figure 
out how to know if the resulting volume is the bounded one (my 
nef_polyhedron) or the unbounded "outter" volume (A similar question has 
been asked some time ago on this list without answer).

About line segments, I cannot rely on the point test, since a line 
segment can intersects a volume, but not its two vertices.

I am currently thinking of converting the Nef_polyhedron to a Polyhedron 
(If I understand correctly, it is done using triangulation underneath, 
right ?) and use intersection tests between Segment_3 and Triangle_3 for 
the "naive" option and AABB trees for something more efficient.
Is there a more "direct" way to do that with CGAL ?

--
Hugo Mercier
Oslandia