Re: [Boost-bugs] [Boost C++ Libraries] #10421: Wrong Pt/Box distance/comparable_distance results in spherical CS

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #10421: Wrong Pt/Box distance/comparable_distance results in spherical CS
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-08-29 13:18:21

#10421: Wrong Pt/Box distance/comparable_distance results in spherical CS
-------------------------------+---------------------------
  Reporter:  awulkiew          |      Owner:  barendgehrels
      Type:  Bugs              |     Status:  new
 Milestone:  To Be Determined  |  Component:  geometry
   Version:  Boost 1.56.0      |   Severity:  Problem
Resolution:                    |   Keywords:
-------------------------------+---------------------------
Description changed by awulkiew:

Old description:

> distance(Pt, Box) and comparable_distance(Pt, Box) returns invalid
> results in some cases, or at least not-corresponding to the Pt/Pt
> versions. E.g. for:
>

> {{{
>     point target(10.932501600000000, 59.922640600000001);
>     point pt(10.7535660, 59.9131705);
>     point pmin(10.187599199999999, 59.747306700000003);
>     point pmax(10.753619700000000, 59.917844000000002);
>     box bounding_box(pmin, pmax);
>
>     bool target_inside_box = bg::covered_by(target, bounding_box);
>     bool point_inside_box = bg::covered_by(pt, bounding_box);
>     // the same for bg::comparable_distance()
>     double dp = bg::distance(target, pt);
>     double db = bg::distance(target, bounding_box);
>     double dm = bg::distance(target, pmax);
> }}}
>
> The results are:
>
> {{{
>     target inside box = FALSE
>     point inside box = TRUE
>     target to point = 0.00157408
>     target to box = 0.178946
>     target to max = 0.00156704
> }}}
>
> Since the point lies inside the box and target outside the box the
> distance from target to box should be smaller than from target to point.
>
> This bug affects the R-tree and is related with this ticket:
> [https://svn.boost.org/trac/boost/ticket/9759

> boost::geometry::index::rtree does not work properly
> spherical_equatorial].

New description:

 distance(Pt, Box) and comparable_distance(Pt, Box) returns invalid results
 in some cases, or at least not-corresponding to the Pt/Pt versions. E.g.
 for:


 {{{
     point target(10.932501600000000, 59.922640600000001);
     point pt(10.7535660, 59.9131705);
     point pmin(10.187599199999999, 59.747306700000003);
     point pmax(10.753619700000000, 59.917844000000002);
     box bounding_box(pmin, pmax);

     bool target_inside_box = bg::covered_by(target, bounding_box);
     bool point_inside_box = bg::covered_by(pt, bounding_box);
     // the same for bg::comparable_distance()
     double dp = bg::distance(target, pt);
     double db = bg::distance(target, bounding_box);
     double dm = bg::distance(target, pmax);
 }}}

 The results are:

 {{{
     target inside box = FALSE
     point inside box = TRUE
     target to point = 0.00157408
     target to box = 0.178946
     target to max = 0.00156704
 }}}

 Since the point lies inside the box and target outside the box the
 distance from target to box should be smaller than from target to point.

 This bug affects the R-tree and is related with this ticket:
 [https://svn.boost.org/trac/boost/ticket/9759

 boost::geometry::index::rtree does not work properly
 spherical_equatorial].

 EDIT: The algorithm uses the cartesian pythagoras_point_box strategy to
 calculate the distance.

--
-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10421#comment:1>
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