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["Bill Conan" <>]

thanks Bart,

i did an experiment, the truth is that if i split an edge e, the newly
generated sub edges will be at the old position of e.

suppose the original edge list is       e1->e2->e3->e4

now if i want to split the e2 to eA and eB, then the list will be like
this     e1->eA->eB->e3->e4

therefore, if i write the code as this:

  Edge_iterator iter=p.edges_begin();
  Edge_iterator iterE=p.edges_end();

  for(iter;iter!=iterE;++iter)
  {
    p.split_edge(iter);
  }

it will loop forever,

the correct code should be like this:

  Edge_iterator iter=p.edges_begin();
  Edge_iterator iterE=p.edges_end();

  for(iter;iter!=iterE;++iter)
  {
    p.split_edge(iter);
    ++iter;
  }

cheers,

On Tue, Jun 17, 2008 at 3:46 AM, Bart Janssens
<>
 wrote:
> On 6/16/08, Bill Conan 
> <>
>  wrote:
>> I'm wondering how people do this kind of operation normally?
>> for example, when applying a subdivision on a geometry object,
>
> Hi Bill,
>
> K-3D meshes used to have a structure similar to the CGAL Halfedge
> structure. To split edges, we traveled along the edges using the
> next() method, making sure to store a handle to the old "next" edge
> before moving on. Pseudo code would be like this:
>
> For each facet
>  Get first edge first_edge
>     while edge != first_edge
>        old_clockwise = edge->next()
>        split edge
>        edge = old_clockwise
>
> Dunno if this is OK in CGAL, though. Also, you might need to make sure
> the opposite edges remain in sync.
>
> Cheers,
>
> --
> Bart
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