CGAL users discussion list

[Pierre Alliez <>]

hi Atul,

I think the feature is not yet in CGAL - but I could provide you with 
hints about how to solve this.

first let's try reformulating your problem:

given a polyhedron (let's assume non self-intersecting and watertight)
and a query point P, you want to know
- if P lies inside or outside the polyhedron.
- the closest distance form P to the polyhedron.

is this right?

Pierre
http://www-sop.inria.fr/members/Pierre.Alliez/


Atul Thakur a écrit :
> Hi all:
>
> I have a Polyhedron_3 and Point_3 and need to find out if the point lies 
> "on the" polyhedron or not <the answer should be true if the point lies 
> on the surface or very near to it, should be false if it lies deep 
> within or totally outside of polyhedron>.
> I think one way of doing this is to determine the distance of the point 
> from each facet plane along its normal of the Polyhedron and then seeing 
> if any of the distance is less than a minimum bound value (say 1e-5). Is 
> this the right way or there exists some neat elegant function to do this 
> check <being a newbie, scanning 3500 pages of manual looks daunting :)>? 
> I saw some functions Polytope distance* but haven't quite understood(may 
> be unrelated).
>
> Any pointers would be really helpful.
>
> sincerely,
> -Atul