Skip to Content.
Sympa Menu

cgal-discuss - Regular_Triangulation_3: dual of an edge

Subject: CGAL users discussion list

List archive

Regular_Triangulation_3: dual of an edge


Chronological Thread 
  • From: "Thomas Zangl - Home" <>
  • To: <>
  • Subject: Regular_Triangulation_3: dual of an edge
  • Date: Wed, 15 Aug 2007 16:32:06 +0200


Hi!

Given a RegularTriangulation3 and a number of edges of this
triangulation. For each of these given edges I try to compute its dual
plane (facet). The plane is formed by the set of vertices which are the
dual of each regular triangulation cell, the edge is part of.

I use some code like this:

(vh1, vh2 are vertex handles of an edge, t = RegularTriangultion3)

Rt_Cell_handle c;
int i, j;
assert(t.is_edge(vh1, vh2, c,i,j));

Rt_Cell_circulator cCirc = t.incident_cells(c, i, j);
Rt_Cell_circulator cCircEnd = cCirc;
PointContainer pDual;
do {
if (!(t.is_infinite(cCirc))) {
Point p = t.dual(cCirc);
pDual.push_back(p);
}
} while(cCirc++!=cCircEnd);

if (pDual.size() == 1 ) {
cout << "hasIntersectionWithPD: got only one point." << endl;
return false;
} else if (pDual.size() == 2) {
cout << "hasIntersectionWithPD: got only one segment." << endl;
return false;
} else if (pDual.size() == 0) {
cout << "hasIntersectionWithPD: Got no dual point? Argl....!" << endl;
return false;
}

I then happens that an edge has 0, 1 or 2 cells around it which
produce the same number of dual points.

Can that be true? I wonder because if an edge of a triangulation has 0
dual points, this means that the edge is only part of infinite
cells?

Best regards,
--
----------------------------------------------------------------
,yours Thomas Zangl, Bakk.rer.soc.oec. -

-
- Freelancer - IT Consulting & Software Development -
- Student of Software Development-Economy (Master) -



Archive powered by MHonArc 2.6.16.

Top of Page