CGAL users discussion list

[Graviton <>]

Thanks, but won't that be a bit slow? Because for every intersection, you need to 
box_self_intersection_d once, and then do_intersect a second time, would that means that I am actually computing the intersection one more time than necessary?

On Tue, Oct 18, 2011 at 2:20 PM, Sebastien Loriot (GeometryFactory) [via cgal-discuss] <[hidden email]> wrote:

On 10/17/2011 11:15 PM, Graviton wrote:

> Hello, I read your link, and look back at the do_intersection API, I
> don't think do_intersection actually takes in a functor, just like how
> box_self_intersection_d

> <http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Box_intersection_d_ref/Function_box_self_intersection_d.html#Cross_link_anchor_1717> does.

> Or is it that one needs to use box_self_intersection_d

> <http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Box_intersection_d_ref/Function_box_self_intersection_d.html#Cross_link_anchor_1717> in

> this case? But isn't box_self_intersection_d

> <http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Box_intersection_d_ref/Function_box_self_intersection_d.html#Cross_link_anchor_1717> is

> supposed to be used for proximity computation, and used when there are
> complicated geometries?
>

The call to do_intersect must be done by you in the functor.
The functor is called each time the bounding boxes intersect.

Sebastien.

> On Tue, Oct 18, 2011 at 1:13 PM, Sebastien Loriot (GeometryFactory) [via

> cgal-discuss] <[hidden email]

> </user/SendEmail.jtp?type=node&node=3914328&i=0>> wrote:
>
>     Have a look at this chapter:
>
>     http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Box_intersection_d/Chapter_main.html
>
>     and in particular the following example you can adapt
>     to polygon. Note that you can also pass a functor instead
>     of a function.
>
>     http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Box_intersection_d/Chapter_main.html#Section_62.5
>

>
>
>     Sebastien.
>
>     On 10/17/2011 07:45 PM, Graviton wrote:
>
>      > I have a list of polygons, and I want to check whether any of
>     them intersect
>      > with others or not ( predicate is sufficient, I just want to know
>     whether A
>      > polygon intersects with B, that's it).
>      >
>      > And since I have a list of polygons, I want to use do_intersect
>     and I want
>      > to keep the index of the intersected polygons. It would be great if
>      > do_intersect also accepts a functor, that is called when an
>     intersection
>      > happens, so that I can store the index of the polygon somewhere.
>      >
>      > --
>      > View this message in context:
>     http://cgal-discuss.949826.n4.nabble.com/do-intersect-visitor-pattern-tp3914108p3914108.html

>      > Sent from the cgal-discuss mailing list archive at Nabble.com.

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

>     ------------------------------------------------------------------------

>     If you reply to this email, your message will be added to the
>     discussion below:
>     http://cgal-discuss.949826.n4.nabble.com/do-intersect-visitor-pattern-tp3914108p3914272.html
>
>     To unsubscribe from do_intersect visitor pattern, click here.
>
>
>

> ------------------------------------------------------------------------
> View this message in context: Re: do_intersect visitor pattern
> <http://cgal-discuss.949826.n4.nabble.com/do-intersect-visitor-pattern-tp3914108p3914328.html>

> Sent from the cgal-discuss mailing list archive

> <http://cgal-discuss.949826.n4.nabble.com/> at Nabble.com.

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

---

If you reply to this email, your message will be added to the discussion below:

http://cgal-discuss.949826.n4.nabble.com/do-intersect-visitor-pattern-tp3914108p3914337.html

To unsubscribe from do_intersect visitor pattern, click here.

---

View this message in context: Re: do_intersect visitor pattern
Sent from the cgal-discuss mailing list archive at Nabble.com.