CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

You have to use a kernel with exact predicates like 
CGAL::Exact_predicates_inexact_constructions_kernel instead of 
CGAL::Simple_cartesian<double>.

More details why here:

https://www.cgal.org/FAQ.html#inexact_NT

Sebastien.


On 4/1/20 6:11 PM, xiaojin wrote:
> In my program, I have
>
> #include <CGAL/Simple_cartesian.h>
> typedef CGAL::Simple_cartesian<double> K;
> typedef K::FT FT;
> typedef K::Ray_3 Ray;
> typedef K::Line_3 Line;
> typedef K::Point_3 Point;
> typedef K::Segment_3 Segment;
> typedef K::Triangle_3 Triangle;
> typedef K::Plane_3 Plane;
> #include <QMainWindow>
> int main(int argc, char *argv[])
> {
>      Point p0(0.103835, -0.0921626, -2.2133);
>      Point p1(0.165068, -0.0411001, -2.28194);
>      Point p2(0.0954547, -0.0170658, -2.23422);
>      Plane plane(p0, p1, p2);
>      std::cout << plane.has_on(p0) << std::endl;
>      std::cout << plane.has_on(p1) << std::endl;
>      std::cout << plane.has_on(p2) << std::endl;
> }
>
> the result is
> 0
> 1
> 1
>
> but the correct result should be:
> 1
> 1
> 1
>
> And is I change the Kernel K as
>
> typedef CGAL::Simple_cartesian<float> K
>
> the result is correct.
>
> So what's the problem? Is there a bug?
>
>
>
>
>
> --
> Sent from: http://cgal-discuss.949826.n4.nabble.com/