[Boost-bugs] [Boost C++ Libraries] #8363: Point-wise coordinate transformation?

Subject: [Boost-bugs] [Boost C++ Libraries] #8363: Point-wise coordinate transformation?
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-04-02 08:04:36

#8363: Point-wise coordinate transformation?
-----------------------------------------------------+----------------------
 Reporter:  Volker Schöch <vschoech@…>               |       Owner:  barendgehrels
     Type:  Support Requests                         |      Status:  new          
Milestone:  To Be Determined                         |   Component:  geometry     
  Version:  Boost 1.52.0                             |    Severity:  Cosmetic     
 Keywords:  transform, iterate, foreach              |  
-----------------------------------------------------+----------------------
 I have asked this question before – about a year ago. Just checking if
 there is any news in this regard: I would like to be able to apply a
 functor to every point in a multi-polygon, e.g., in order to transform an
 int-based polygon into a double-base polygon. This seems to be a canonical
 operation, like boost::adaptors::transform on ranges, and yet as far as I
 know there is no algorithm for this in geometry. This is how I currently
 do it:

 {{{
 reserve( polygon.size() ); // vector of polygons
 for( std::vector< _TPolygon< S >::polygon_type >::const_iterator
 itp=polygon.begin(); itp!=polygon.end(); ++itp ) {
        emplace_back( polygon_type() );
        back().outer().reserve( itp->outer().size() ); // vector of points
 describing polygon outline
        for( _TPolygon< S >::polygon_type::ring_type::const_iterator
 itouter=itp->outer().begin(); itouter!=itp->outer().end(); ++itouter ) {
              back().outer().emplace_back( _TPoint< T >(*itouter) );
        }
        back().inners().reserve( itp->inners().size() ); // vector of holes
        for( _TPolygon< S
 >::polygon_type::inner_container_type::const_iterator
 itinners=itp->inners().begin(); itinners!=itp->inners().end(); ++itinners
 ) {
              back().inners().emplace_back( polygon_type::ring_type() );
              back().inners().back().reserve( itinners->size() ); // vector
 of points describing a hole
              for( _TPolygon< S >::polygon_type::ring_type::const_iterator
 itinner=itinners->begin(); itinner!=itinners->end(); ++itinner ) {
                     back().inners().back().emplace_back( _TPoint< T
 >(*itinner) );
              }
        }
 }
 }}}

 Is there an algorithm in geometry 1.52.0 that I did not find? Do you plan
 to add an algorithm for this task at some point?

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/8363>
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