Re: [Boost-bugs] [Boost C++ Libraries] #9941: bg::touches() for box geometries

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #9941: bg::touches() for box geometries
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-04-23 15:02:36

#9941: bg::touches() for box geometries
-------------------------------+----------------------------
  Reporter:  Frank             |      Owner:  barendgehrels
      Type:  Feature Requests  |     Status:  new
 Milestone:  To Be Determined  |  Component:  geometry
   Version:  Boost 1.55.0      |   Severity:  Not Applicable
Resolution:                    |   Keywords:  touches, box
-------------------------------+----------------------------

Comment (by awulkiew):

 I pushed the implementation to the develop. However there is an edge case
 when both Boxes are Point-sized, e.g.: box(pt(0 0,0 0), pt(0 0,0 0)).

 Spatial relations are well defined, e.g. touches() returns TRUE only if
 the interiors of both geometries do NOT overlap.

 In the case of Polygons we know what to do because according to the OGC
 the Polygon must have an interior, it's area can't be 0. Boxes are
 different, they're not defined in the OGC standard. Bounding objects in
 general may have no area/volume since they may be an envelop of a single
 Point. So we should decide how a Point-sized Box should be treated:
 1. as a Point - no boundary, only the interior which means that touches
 for equal Point-sized Boxes should return FALSE.
 2. as an Areal geometry without interior, only boundary which means that
 touches for equal Point-sized Boxes should return TRUE (currently this is
 implemented).

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9941#comment:3>
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