psimpl::PolylineSimplification< DIM, InputIterator, OutputIterator >::DPHelper Class Reference

Douglas-Peucker approximation helper class. More...

Classes
struct	KeyInfo
	Defines the key of a polyline. More...
struct	SubPoly
	Defines a sub polyline. More...
struct	SubPolyAlt
	Defines a sub polyline including its key. More...

Static Public Member Functions
static void	Approximate (const value_type *coords, ptr_diff_type coordCount, value_type tol, unsigned char *keys)
	Performs Douglas-Peucker approximation. More...
static void	ApproximateN (const value_type *coords, ptr_diff_type coordCount, unsigned countTol, unsigned char *keys)
	Performs Douglas-Peucker approximation. More...

Static Private Member Functions
static KeyInfo	FindKey (const value_type *coords, ptr_diff_type first, ptr_diff_type last)
	Finds the key for the given sub polyline. More...

Detailed Description

template<unsigned DIM, class InputIterator, class OutputIterator>
class psimpl::PolylineSimplification< DIM, InputIterator, OutputIterator >::DPHelper

Douglas-Peucker approximation helper class.

Contains helper implentations for Douglas-Peucker approximation that operate solely on value_type arrays and value_type pointers. Note that the PolylineSimplification class only operates on iterators.

Definition at line 1457 of file psimpl.h.

Member Function Documentation

Approximate()

template<unsigned DIM, class InputIterator, class OutputIterator>

static void psimpl::PolylineSimplification< DIM, InputIterator, OutputIterator >::DPHelper::Approximate ( const value_type *  coords, ptr_diff_type  coordCount, value_type  tol, unsigned char *  keys  )

inlinestatic

Performs Douglas-Peucker approximation.

Parameters

[in]	coords	array of polyline coordinates
[in]	coordCount	number of coordinates in coords []
[in]	tol	approximation tolerance
[out]	keys	indicates for each polyline point if it is a key

Definition at line 1500 of file psimpl.h.

ApproximateN()

template<unsigned DIM, class InputIterator, class OutputIterator>

static void psimpl::PolylineSimplification< DIM, InputIterator, OutputIterator >::DPHelper::ApproximateN ( const value_type *  coords, ptr_diff_type  coordCount, unsigned  countTol, unsigned char *  keys  )

inlinestatic

Performs Douglas-Peucker approximation.

Parameters

[in]	coords	array of polyline coordinates
[in]	coordCount	number of coordinates in coords []
[in]	countTol	point count tolerance
[out]	keys	indicates for each polyline point if it is a key

Definition at line 1541 of file psimpl.h.

FindKey()

template<unsigned DIM, class InputIterator, class OutputIterator>

static KeyInfo psimpl::PolylineSimplification< DIM, InputIterator, OutputIterator >::DPHelper::FindKey ( const value_type *  coords, ptr_diff_type  first, ptr_diff_type  last  )

inlinestaticprivate

Finds the key for the given sub polyline.

Finds the point in the range [first, last] that is furthest away from the segment (first, last). This point is called the key.

Parameters

[in]	coords	array of polyline coordinates
[in]	first	the first coordinate of the first polyline point
[in]	last	the first coordinate of the last polyline point

Returns

the index of the key and its distance, or last when a key could not be found

Definition at line 1602 of file psimpl.h.

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The documentation for this class was generated from the following file:

• psimpl.h