[ceph.git] / ceph / src / boost / libs / geometry / doc / reference / algorithms / within.qbk

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

  Copyright (c) 2009-2012 Barend Gehrels, Amsterdam, the Netherlands.
  Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
  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)
=============================================================================/]

[def __this_function__ within]

[heading_conformance_ogc __this_function__..Within]
[note OGC defines within as completely within and not on the border. See the notes for within / on the border]

[include reference/status/within_status.qbk]
[note In this status matrix above: columns are types of first parameter
  and rows are types of second parameter. So a point can be checked to be 
  within a polygon, but not vice versa.]
  
[heading Notes]
If a point is located exactly on the border of a geometry, the result depends on the strategy.
The default strategy ([link geometry.reference.strategies.strategy_within_winding Winding (coordinate system agnostic)]) 
returns false in that case.

If a polygon has a reverse oriented (e.g. counterclockwise for a clockwise typed polygon), the result also depends on the strategy.
The default strategy returns still true if a point is completely within the reversed polygon. There is a specific strategy which returns false in this case.

[heading Complexity]
Linear

[heading See also]
* [link geometry.reference.algorithms.covered_by covered_by]
Commit	Line	Data
7c673cae FG	1	[/============================================================================
	2	Boost.Geometry (aka GGL, Generic Geometry Library)
	3
	4	Copyright (c) 2009-2012 Barend Gehrels, Amsterdam, the Netherlands.
	5	Copyright (c) 2009-2012 Mateusz Loskot, London, UK.
	6	Copyright (c) 2009-2012 Bruno Lalande, Paris, France.
	7
	8	Use, modification and distribution is subject to the Boost Software License,
	9	Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
	10	http://www.boost.org/LICENSE_1_0.txt)
	11	=============================================================================/]
	12
	13	[def __this_function__ within]
	14
	15	[heading_conformance_ogc __this_function__..Within]
	16	[note OGC defines within as completely within and not on the border. See the notes for within / on the border]
	17
	18	[include reference/status/within_status.qbk]
	19	[note In this status matrix above: columns are types of first parameter
	20	and rows are types of second parameter. So a point can be checked to be
	21	within a polygon, but not vice versa.]
	22
	23	[heading Notes]
	24	If a point is located exactly on the border of a geometry, the result depends on the strategy.
	25	The default strategy ([link geometry.reference.strategies.strategy_within_winding Winding (coordinate system agnostic)])
	26	returns false in that case.
	27
	28	If a polygon has a reverse oriented (e.g. counterclockwise for a clockwise typed polygon), the result also depends on the strategy.
	29	The default strategy returns still true if a point is completely within the reversed polygon. There is a specific strategy which returns false in this case.
	30
	31	[heading Complexity]
	32	Linear
	33
	34	[heading See also]
	35	* [link geometry.reference.algorithms.covered_by covered_by]