CGAL users discussion list

[Andreas Fabri <>]

Hi Marc,

As the plane is internally a point and a normal  this is a construction.
So if the point is slightly off the plane of the triangle and the normal
happens to be correct the plane and the triangle plane  are parallel.

Even if one takes a vertex of the triangle as base for the plane
there is no guarantee that the intersection is  the full triangle.

andreas

On 5/17/21 7:07 PM, Marc Alexa ( via cgal-discuss 
Mailing List) wrote:
> Dear all,
>
> I’m a checking the intersection between Triangle_3 and Plane_3 objects. If 
> both are constructed from the same triple of points, the result is false for 
> most triples, but sometimes true. I’m using the exact predicates / inexact 
> constructions kernel. Is this the expected / desired behavior? I had hope 
> because of the exact predicates that the result for such intersection tests 
> is at least consistent (and actually consistently true).
>
> Thanks!
> -Marc