VgPositionToolbox Class Reference

Public Member Functions
double	computeDistance (VgPositionVector pPositions)
double	computeDistance (VgPosition pPos1, VgPosition pPos2)
double	computeHeadingAngle (VgPosition pPosPivot, VgPosition pPos1, VgPosition pPos2)
double	computePitchAngle (VgPosition pPosPivot, VgPosition pPos1, VgPosition pPos2)
VgPosition	computeMiddlePoint (VgPosition pPos1, VgPosition pPos2)
VgPosition	offsetPosition (VgPosition pPosition, double pHeadingInDegrees, double pPitchInDegrees, double pDistanceInMeters)
VgSRSRefPtr	editGeoReferencedSRS ()
VgSRSConstRefPtr	getGeoReferencedSRS ()
VgSRSRefPtr	editSceneSRS ()
VgSRSConstRefPtr	getSceneSRS ()
void	convert (VgPosition pPos, VgSRSConstRefPtr pSRS)
void	geoConvert (VgPosition pPos, VgSRSConstRefPtr pSRS)
VgPositionVector	simplifyLineForWidth (VgPositionVector pPositions, double pWidth)
boolean	isInside2D (VgPosition pPosition, VgPositionVector pPolygon)

Detailed Description

Provides various utility methods for VgEngine::VgPosition

Member Function Documentation

double VgPositionToolbox.computeDistance

(

VgPositionVector

pPositions

)

Computes the distance in meters from an ordered sequence of positions.

Remarks

Computes a cartesian distance, not geodesic.

Parameters

pPositions

An ordered sequence of positions.

Returns

The total distance in meters. 0.0 if the parameter pPositions contains 0 or 1 elements. NaN if an error occurs.

double VgPositionToolbox.computeDistance	(	VgPosition	pPos1,
		VgPosition	pPos2
	)

Computes the distance in meters between two positions.

Remarks

it computes a cartesian distance, not geodesic.

Parameters

pPos1	Position one
pPos2	Position two

Returns

The distance in meters. NaN if an error occurs.

double VgPositionToolbox.computeHeadingAngle	(	VgPosition	pPosPivot,
		VgPosition	pPos1,
		VgPosition	pPos2
	)

Computes the heading angle, in degrees, between Pos1-Pivot and Pos2-Pivot.

Parameters

pPosPivot	Pivot Position
pPos1	Position one
pPos2	Position two

Returns

Heading angle in degrees [0,360] (0 for north, increasing in value starting from the east). If at least two positions are equal, the result is undefined. NaN if an error occurs.

VgPosition VgPositionToolbox.computeMiddlePoint	(	VgPosition	pPos1,
		VgPosition	pPos2
	)

Computes the middle point of two positions. The positions will be converted to scene SRS with geographic coherence before computing. The result position will be expressed in the georeferenced SRS.

Parameters

pPos1	The first position.
pPos2	The second position.

Version

2.0.8955

Returns

The middle point's position in the georeferenced SRS.

double VgPositionToolbox.computePitchAngle	(	VgPosition	pPosPivot,
		VgPosition	pPos1,
		VgPosition	pPos2
	)

Computes the pitch angle, in degrees, between Pos1-Pivot and Pos2-Pivot.

Parameters

pPosPivot	Pivot Position
pPos1	Position 1
pPos2	Position 2

Returns

Pitch angle in degrees [-90,90] (0 to look "forward" towards the horizon, negative values look down). NaN if an error occurs.

void VgPositionToolbox.convert	(	VgPosition	pPos,
		VgSRSConstRefPtr	pSRS
	)

Utility method to convert a position to a given SRS.

Note

No conversion will take place if the Geograhpical SRS hasn't been initialised. The Geograhpical SRS is initialised as a result of calling the VgIDatabase::selectDataset() method.

Parameters

pPos	The position to convert.
pSRS	The spatial reference system in which to convert the position. If NULL it is assumed that WGS84 is wanted.

Version

2.0

VgSRSRefPtr VgPositionToolbox.editGeoReferencedSRS

(

)

Returns the engine's main georeferenced SRS.

Version

2.0

VgSRSRefPtr VgPositionToolbox.editSceneSRS

(

)

Returns the scene's metric SRS.

Version

2.0

void VgPositionToolbox.geoConvert	(	VgPosition	pPos,
		VgSRSConstRefPtr	pSRS
	)

Utility method to convert a position to a given SRS with geographic coherence.

Parameters

pPos	The position to convert.
pSRS	The spatial reference system in which to convert the position. If NULL it is assumed that WGS84 is wanted.

Version

2.0.8955

VgSRSConstRefPtr VgPositionToolbox.getGeoReferencedSRS

(

)

Returns the engine's main georeferenced SRS.

Version

2.0

VgSRSConstRefPtr VgPositionToolbox.getSceneSRS

(

)

Returns the scene's metric SRS.

Version

2.0

boolean VgPositionToolbox.isInside2D	(	VgPosition	pPosition,
		VgPositionVector	pPolygon
	)

Utility to determine if a position is inside a polygon

Parameters

pPosition	position to test
pPolygon	vector of points, it assumes the VgSRS of all its points are the same, it should have at least 3 elements.

Version

2.1.4

Returns

true if pPosition is inside the polygon defined by pPolygon points.

VgPosition VgPositionToolbox.offsetPosition	(	VgPosition	pPosition,
		double	pHeadingInDegrees,
		double	pPitchInDegrees,
		double	pDistanceInMeters
	)

Offsets a position with a distance in meters given a direction.

Parameters

pPosition	Start position
pHeadingInDegrees	Heading in degrees [0,360] (0 for north, increasing value start to east).
pPitchInDegrees	Pitch in degrees [-90,90] (0 to look "forward" towards the horizon, negative values to look down)
pDistanceInMeters	Distance in meters

Returns

Offset position. If an error occurs, all components of the position are set to NaN.

VgPositionVector VgPositionToolbox.simplifyLineForWidth	(	VgPositionVector	pPositions,
		double	pWidth
	)

Utility to simplify a line (vector of positions) such that the resulting line is simpler and its turn's radius is wider than half the width. This function for advanced users is used for computing positions and subsequently creating lines to be seen at different distances.

Parameters

pPositions	input vector of positions
pWidth	The width of the line that is to be simplified. The larger the width, the greater the simplifiction of the line's position vector.

Version

2.0.8955

Returns

new positions vector with less or equal number of points.

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

• VgPositionToolbox.java