topoCoord.h File Reference

This file contains useful functions for geocentric to topographic conversions. More...

Go to the source code of this file.

Functions
void	DtLatLon_to_TopoToGeoc (const DtGeodeticCoord &g, DtDcmRef topoToGeoc)
	Any point on the globe can be used to specify the origin of a specific topographic coordinate system.
void	DtLatLon_to_GeocToTopo (const DtGeodeticCoord &g, DtDcmRef geocToTopo)
	The matrix produced by DtLatLon_to_GeocToTopo can be used to rotate a geocentric vector to a topographic vector like this: DtDcmVecMul(geocToTopo, Vgeoc, Vtopo);.
void	DtGeocToTopoTransform (double latitude, double longitude, DtCoordTransform *geoc2topo)
	This function can initialize a DtCoordTransform so that it can provide transformations between the geocentric coordinate system, and a particular topographic coordinate system defined by latitude and longitude.

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Detailed Description

This file contains useful functions for geocentric to topographic conversions.

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Function Documentation

void DtGeocToTopoTransform	(	double	latitude,
		double	longitude,
		DtCoordTransform *	geoc2topo
	)

This function can initialize a DtCoordTransform so that it can provide transformations between the geocentric coordinate system, and a particular topographic coordinate system defined by latitude and longitude.

void DtLatLon_to_GeocToTopo	(	const DtGeodeticCoord &	g,
		DtDcmRef	geocToTopo
	)

The matrix produced by DtLatLon_to_GeocToTopo can be used to rotate a geocentric vector to a topographic vector like this: DtDcmVecMul(geocToTopo, Vgeoc, Vtopo);.

void DtLatLon_to_TopoToGeoc	(	const DtGeodeticCoord &	g,
		DtDcmRef	topoToGeoc
	)

Any point on the globe can be used to specify the origin of a specific topographic coordinate system.

In VR-Link, a topographic frame is defined with the positive X axis pointing north, the positive Y axis pointing east, and the positive Z axis pointing down. From latitude and longitude, we can produce the rotation matrices that rotate between geocentric and topographic-down orientations. VR-Link uses post-multiplication for its rotation matrices. For example, the matrix produced by DtLatLon_to_TopoToGeoc can be used to rotate a topographic vector to a geocentric vector like this: DtDcmVecMul( topoToGeoc, Vtopo, Vgeoc );