DM::GeometricAlgorithms Namespace Reference

provides a set of geometric algorithms (Douglas-Peucker algorithm, densification of lines) More...

Functions
DM_API DM::PolylineHandle	thinOut (const DM::PolylineHandle &line, double maxOrthoDist)
	Use the Douglas-Peucker algorithm to create a polyline with a subset of vertices of the provided line object. More...
DM_API DM::PolylineHandle	densify (const DM::PolylineHandle &line, double maxSpacing)
	densify a polyline by inserting new points along the line segments More...
DM_API bool	isSelfIntersecting (const DM::PolylineHandle &line)
	test if a polyline is self intersecting
DM_API void	analyseDistance (const PolylineHandle &base, const PolylineHandle &other, IAnalyseDistance &callback, double maxDist=-1, bool d3=true)
	For analysing 2d/3d distances between vertices of the base polyline to the other provided polyline (optional a max distance threshold is considered) More...

Detailed Description

provides a set of geometric algorithms (Douglas-Peucker algorithm, densification of lines)

Function Documentation

analyseDistance()

DM_API void DM::GeometricAlgorithms::analyseDistance	(	const PolylineHandle &	base,
		const PolylineHandle &	other,
		IAnalyseDistance &	callback,
		double	maxDist = -1,
		bool	d3 = true
	)

For analysing 2d/3d distances between vertices of the base polyline to the other provided polyline (optional a max distance threshold is considered)

The function computes the shortest 2d/3d distances of all vertices of the base polyline to the 'other' polyline. With the results of each base vertex distance computation the corresponding function of the provided callback object is called. If an maximum distance threshold is provided (maxDist>0), the algorithms only considers distances up to the given threshold (see IAnalyseDistance). The implemented algorithm uses the maxDist threshold during spatial search and therfore, is more efficient than only handling the distance threshold within the callback oject.

Parameters

[in]	base	the vertex of the base polyline is used for distance analysis
[in]	other	polyline to which the distances are computed
[in]	callback	callback object for analysing the computed distance results
[in]	maxDist	optional maximum distance threshold (-1: no distance threshold is applied)
[in]	d3	flag if 3d or 2d computation (true: 3d / false: 2d)

densify()

DM_API DM::PolylineHandle DM::GeometricAlgorithms::densify	(	const DM::PolylineHandle &	line,
		double	maxSpacing
	)

densify a polyline by inserting new points along the line segments

insert as few points as possible to reach the criterion:
(distances between neighbours) <= d_maxSpacing
distribute the new points equally along each line segment
preserve original points together with their additional infos

Parameters

[in]	line	polyline that should be densified
[in]	maxSpacing	maximum spacing between neighboring vertices

Returns

resulting object

thinOut()

DM_API DM::PolylineHandle DM::GeometricAlgorithms::thinOut	(	const DM::PolylineHandle &	line,
		double	maxOrthoDist
	)

Use the Douglas-Peucker algorithm to create a polyline with a subset of vertices of the provided line object.

Each polyline part is treated as a separate object

Parameters

[in]	line	polyline that should be thinned out
[in]	maxOrthoDist	Discarded vertices feature an orthogonal distance to the returned polyline <= d_maxOrthoDist

Returns

resulting object