CGAL users discussion list

[Oleg <>]

Sebastien Loriot (GeometryFactory) wrote
> 
> Note that the intersection might be not a segment.
> See
> http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Kernel_23_ref/Function_intersection.html
> 

I know, but my goal is to come up with polyline of intersection of two
triangulated surfaces, so the points won't matter here and I can ignore
them.



> Also if the triangle comes from the same polyhedron, you might want to use
> incidence of faces using opposite relations of halfedges.
> 

I will try this way, thanks! But for starters I'd just like to see what the
intersection segments are. Any hint how I should correct the code to get the
segments into a file?



> Is the vector empty or
> 

It is empty while there definitely are intersections (I output the
intersecting triangles into a file, and it is not empty).

On Tuesday, March 20, 2012, Oleg <olegs@> wrote:
> Hi all! Another newbie question. I want to find intersection segment of
two
> triangles. I take Polyhedron\polyhedron_self_intersection.cpp example as
the
> starting point and add this piece of code:
>
> --> std::vector<Segment> segments;
> ...
> Triangle t1( h->vertex()->point(),
>                 h->next()->vertex()->point(),
>                 h->next()->next()->vertex()->point());
> Triangle t2( g->vertex()->point(),
>                 g->next()->vertex()->point(),
>                 g->next()->next()->vertex()->point());
> if ( CGAL::do_intersect( t1, t2)) {
> //cerr << "Triangles intersect:\n    T1: " << t1 << "\n    T2 :"
> //     << t2 << endl;
> triangles.push_back(t1);
> triangles.push_back(t2);
> --> CGAL::Object obj = CGAL::intersection(t1, t2);
> --> Segment seg;
> --> if (assign(seg, obj)) segments.push_back(seg);
> }
> ...
>
> In the output I get empty vector segments. What I'm doing wrong?

-- 
You are currently subscribed to cgal-discuss.
To unsubscribe or access the archives, go to
https://lists-sop.inria.fr/wws/info/cgal-discuss



--
View this message in context: 
http://cgal-discuss.949826.n4.nabble.com/Finding-intersection-segment-tp4488033p4488382.html
Sent from the cgal-discuss mailing list archive at Nabble.com.