CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

yanyajie wrote:
> ?But how can the existing fuzzy object know if it contains my point or 
> not? Isn't there supposed to be some new "bool contain(PointType p)" 
> which does this?
It uses the functor Construct_cartesian_const_iterator_d.

S.

> 
> -----原始邮件----- From: Sebastien Loriot (GeometryFactory)
> Sent: Wednesday, March 30, 2011 11:45 PM
> To: 
> 
> Subject: Re: [cgal-discuss] how to extend kd-tree to range-query user 
> defined point?
> 
> yanyajie wrote:
>> ?Dear S,
>>
>> I see. Just to be sure: practiacally I need to provide a new query item
>> (box or sphere), my new point type, and wrap them in a new SearchTraits,
>> right?
>>
> Not a new fuzzy object, as you can provide your traits as
> template parameter to CGAL::Fuzzy_sphere and CGAL::Fuzzy_iso_box.
> 
> you simply need to define
> struct Search_traits_with_my_point{
>    typedef XXX Cartesian_const_iterator_d;
>    typedef XXX Construct_cartesian_const_iterator_d;
>    typedef XXX Point_d;
>    typedef XXX Iso_box_d;
>    typedef XXX Sphere_d;
>    typedef XXX Construct_iso_box_d;
> 
>    typedef XXX Construct_min_vertex_d;
>    typedef XXX Construct_max_vertex_d;
>    typedef XXX Construct_center_d;
>    typedef XXX Compute_squared_radius_d;
>    typedef XXX FT;
> 
> };
> 
> For the details see:
> http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Spatial_searching_ref/Concept_SearchTraits.html
>  
> 
> 
> S.
> 
>> Yan.
>>
>> -----原始邮件----- From: Sebastien Loriot (GeometryFactory)
>> Sent: Wednesday, March 30, 2011 8:42 PM
>> To: 
>> 
>> Subject: Re: [cgal-discuss] how to extend kd-tree to range-query user
>> defined point?
>>
>> There is a bug in the documentation we are aware of and that should be
>> fixed in the 3.9 release. Search_traits is not a real model of the
>> SearchTraits concept as it cannot be used for range-search queries.
>>
>> It should not be hard to define your own traits class using this concept
>> page:
>> http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Spatial_searching_ref/Concept_SearchTraits.html#Cross_link_anchor_1634
>>  
>>
>>
>>
>>
>> For a concise view you can also have a look at
>> include/CGAL/Search_traits_2.h (which simply contains types that
>> need to be defined)
>>
>> Basically you simply have to define more functors than in the example
>> here:
>>
>> http://www.cgal.org/Manual/latest/doc_html/cgal_manual/Spatial_searching/Chapter_main.html#Subsection_59.3.5
>>  
>>
>>
>>
>>
>> S.
>>
>>
>>
>>
>>
>> yanyajie wrote:
>>> Hi,
>>>
>>> I have a specific point type, known as surfel. I would like to build a
>>> kd-tree for a bunch of surfels and to do range-query specified by a
>>> sphere queryitem. How can I extend the kd-tree to achieve my goal?
>>>
>>> I examined the search() routine in kd_tree_node.h and found kd_tree
>>> heavily rely on the query item’s contains() member to do actual query.
>>> Does that mean all I have to do is just implement my own extended
>>> version of query item, like a sphere, so that it can determine whether
>>> or not a surfel is contained in? Or do I have to provide another
>>> distance class as exemplified in the example?
>>>
>>> Really need some help here. Thanks in advance!!!
>>>
>>> Yan.
>>>
>>>
>>>
>>> -------------------------------------------------------------------------------------
>>>  
>>>
>>>
>>> * The State Key Labratory of Virtual Reality and Technology
>>> * School of Computer Science and Engineering
>>> * Beijing University Aeronautics and Astronautics (Beihang Univ.)
>>> -------------------------------------------------------------------------------------
>>>  
>>>
>>>
>>
>>
> 
>