add subtree-ish sources for 12.0.3

[ceph.git] / ceph / src / boost / libs / geometry / doc / concept / linestring.qbk

[/============================================================================
  Boost.Geometry (aka GGL, Generic Geometry Library)

  Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
  Copyright (c) 2009-2012 Barend Gehrels, Amsterdam, the Netherlands.
  Copyright (c) 2009-2012 Bruno Lalande, Paris, France.

  Use, modification and distribution is subject to the Boost Software License,
  Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  http://www.boost.org/LICENSE_1_0.txt)
=============================================================================/]

[section:concept_linestring Linestring Concept]

[heading Description]
[concept Linestring..linestring]

A linestring is ['a Curve with linear interpolation between Points]. 
(__ogc_sf__).

[heading Concept Definition]

The Linestring Concept is defined as following:

* there must be a specialization of `traits::tag` defining `linestring_tag` as type
* it must behave like a Boost.Range Random Access Range
* The type defined by the metafunction `range_value<...>::type` must fulfill 
	the [link geometry.reference.concepts.concept_point Point Concept]

[heading Rules]

Besides the Concepts, which are checks on compile-time, there are rules that
valid linestrings must fulfill. Most algorithms work on any linestring, so either
self-crossing or not. However, for correct results using the overlay algorithms
(intersection and difference algorithms in combination with a polygon) 
self-intersections can disturb the process and result in incorrect results.
    
[heading Available Models]	
* [link geometry.reference.models.model_linestring model::linestring]
* a std::vector (requires registration)
* a std::deque (requires registration)

[see_boost_range_sample Linestring]

[endsect]