This class defines the Mercator projection. More...

#include <ilviews/maps/projection/mercator.h>

Inheritance diagram for IlvMercatorProjection:

Public Member Functions
	IlvMercatorProjection (IlDouble latitudeOfTrueScale=0.)
	Creates an instance of the class `IlvMercatorProjection` and specifies the latitude of the true scale. More...

IlDouble	getLatitudeOfTrueScale () const
	Returns the latitude of the true scale in radian. More...

virtual IlvMapsError	setEllipsoid (const IlvEllipsoid &ellipsoid)
	Sets the ellipsoid used for the projection. More...

void	setLatitudeOfTrueScale (IlDouble latitudeOfTrueScale)
	Sets the latitude of the true scale in radian. More...

virtual void	write (IlvOutputFile &) const
	Saves the parameters of a projection to the specified output file. More...

Public Member Functions inherited from IlvProjection
virtual IlvProjection *	copy () const =0
	Returns a copy of the projection. More...

IlvMapsError	forward (const IlvCoordinate &llIn, IlvCoordinate &xyOut) const
	Converts a latitude and a longitude to Cartesian coordinates (x,y). More...

IlvMapsError	forward (IlvCoordinate &x) const
	This member function converts a latitude and a longitude to Cartesian coordinates. More...

IlDouble	getCentralMeridian () const
	Returns the central meridian of the projection. More...

IlDouble	getCentralParallel () const
	Returns the central parallel of the projection. More...

virtual IlvProjectionClassInfo *	getClassInfo () const
	Returns the class information for the projection. More...

const IlvHorizontalDatum *	getDatum (void) const
	Returns the horizontal datum used for the projection. More...

const IlvEllipsoid *	getEllipsoid () const
	Returns the ellipsoid used for the projection. More...

IlvMapsError	getError () const
	Returns the status of the projection. More...

IlDouble	getFalseEasting () const
	Returns the false easting of the projection. More...

IlDouble	getFalseNorthing () const
	Returns the false northing of the projection. More...

IlvProjectionInterface *	getInterface ()
	Returns the interface of the projection. More...

IlvCoordinate	getLLCenter (void) const
	Returns the central meridian and the central parallel associated with the projection (0-0 by default). More...

IlvProjectionGeometricProperty	getProperty () const
	Returns the geometric property of the projection. More...

const IlvUnitConverter *	getUnitConverter () const
	Returns the unit converter. More...

IlvCoordinate	getXYOffset () const
	Returns the false easting and the false northing of the projection. More...

IlvMapsError	inverse (const IlvCoordinate &xyIn, IlvCoordinate &llOut) const
	Converts the specified coordinate to a latitude and a longitude. More...

IlvMapsError	inverse (IlvCoordinate &x) const
	Converts the `IlvCoordinate` representing Cartesian coordinates to a latitude and a longitude. More...

IlBoolean	isBad () const
	Checks for an inconsistent state of the projection. More...

IlBoolean	isEllipsoidEnabled () const
	Indicates if non spherical ellipsoids can be used for the projection. More...

IlBoolean	isGeocentric () const
	Checks if the projection uses geocentric latitudes. More...

IlBoolean	isInverseEnabled () const
	Indicates if the inverse function is supported by the projection. More...

IlBoolean	isShared () const
	Indicates that the projection is shared. More...

IlBoolean	isUsingLongitudeReduction () const
	Returns `IlTrue` if the projection uses range reduction for longitudes. More...

void	lock ()
	Locks the projection.

virtual std::ostream &	printPROJ4Descriptor (std::ostream &ostr, IlvMapsError *status=0) const
	This virtual member function converts the projection to a string in the `PROJ4` format. More...

void	save (IlvOutputFile &outputFile) const
	Saves an instance of a subclass of `IlvProjection` to the specified output file. More...

void	setCentralMeridian (IlDouble lon)
	Sets the central meridian of the projection. More...

void	setCentralParallel (IlDouble lat)
	Sets the central parallel of the projection. More...

virtual IlvMapsError	setDatum (const IlvHorizontalDatum *datum)
	Sets the datum used for the projection. More...

void	setFalseEasting (IlDouble falseEasting)
	Sets the false easting of the projection. More...

void	setFalseNorthing (IlDouble falseNorthing)
	Sets the false northing of the projection. More...

void	setGeocentric (IlBoolean geoc)
	Specifies whether the projection uses geocentric or geodetic latitudes. More...

virtual void	setLLCenter (IlDouble lon, IlDouble lat)
	Specifies the central meridian and the central parallel (in radian) associated with the projection. More...

void	setShared ()
	Specifies that the projection will be shared. More...

void	setUnitConverter (const IlvUnitConverter &converter)
	Sets the unit converter of the projection. More...

void	setUsingLongitudeReduction (IlBoolean use)
	Specifies whether the projection uses longitude reduction. More...

void	setXYOffset (IlDouble x0, IlDouble y0)
	Specifies the false easting and the false northing. More...

void	unLock ()
	Unlocks the object. More...

Protected Member Functions
virtual IlvMapsError	eForward (IlvCoordinate &ll) const
	Must be redefined in subclasses to implement the projection for a non spherical ellipsoid. More...

virtual IlvMapsError	eInverse (IlvCoordinate &xy) const
	Implements the inverse projection for a non spherical ellipsoid. More...

virtual IlvMapsError	sForward (IlvCoordinate &ll) const
	Must be redefined in subclasses to implement the projection for a sphere. More...

virtual IlvMapsError	sInverse (IlvCoordinate &xy) const
	Must be redefined in subclasses to implement the inverse projection for a sphere. More...

Protected Member Functions inherited from IlvProjection
	IlvProjection (IlBoolean ellipsoidEnabled, IlBoolean inverseEnabled, IlvProjectionGeometricProperty property)
	Initializes a new `IlvProjection` object. More...

void	addError (IlvMapsError error)
	Used by the constructors of subclasses if an error occurs during an object initialization. More...

void	setError (IlvMapsError error)
	Sets the status of this projection. More...

Additional Inherited Members
Static Public Member Functions inherited from IlvProjection
static IlvProjectionClassInfo *	ClassInfo ()
	Returns the class information of the class. More...

static IlvClassInfo **	ClassInfoRef ()
	Returns the address of the class information of the class. More...

static IlvMapsError	InputError ()
	Indicates that the coordinates passed to the forward function are not in a valid range for radian angles.

static IlvMapsError	InvalidEllipsoidError ()
	Indicates that you attempt to set a non spherical ellipsoid to a projection that does not support non spherical ellipsoids.

static IlvProjection *	Load (IlvInputFile &inputFile)
	Loads a projection from the specified file. More...

static IlvProjection *	PROJ4ToIlvProjection (const char proj4Descriptor, IlvMapsError status=0)
	Creates the projection from a `PROJ4` descriptor. More...

static IlvMapsError	ToleranceConditionError ()
	Indicates that an internal projection computation failed. More...

static IlvMapsError	UnsupportedFeatureError ()
	Indicates that an unsupported projection feature is requested, like inverse projection for a projection that does not support inverse projection.

Detailed Description

This class defines the Mercator projection.

The Mercator projection, also known as the Wright projection, is the projection of a sphere on a cylinder that is tangent to the equator. Mercator projections should be limited to equatorial regions, but are frequently used for navigational charts with a latitude of the true scale specified within or near the chart boundaries. With this projection, the regions near the poles cannot be shown.
This projection applies both to spherical and non-spherical ellipsoids and implements an inverse function.
This projection is Conformal.

Mercator Projection

Library: ilvmaps

Constructor & Destructor Documentation

§ IlvMercatorProjection()

IlvMercatorProjection::IlvMercatorProjection ( IlDouble latitudeOfTrueScale = 0. )

Creates an instance of the class IlvMercatorProjection and specifies the latitude of the true scale.

Parameters

latitudeOfTrueScale The latitude of the true scale.

Member Function Documentation

§ eForward()

virtual IlvMapsError IlvMercatorProjection::eForward ( IlvCoordinate & ll ) const

protectedvirtual

Must be redefined in subclasses to implement the projection for a non spherical ellipsoid.

The default implementation returns IlvProjection::UnsupportedFeatureError().

Parameters

ll	Contains the longitude and latitude coordinates in radian (x = longitude, y = latitude).

Returns: An error code.

Reimplemented from IlvProjection.

§ eInverse()

virtual IlvMapsError IlvMercatorProjection::eInverse ( IlvCoordinate & xy ) const

protectedvirtual

Implements the inverse projection for a non spherical ellipsoid.

The default implementation returns IlvProjection::UnsupportedFeatureError().

Parameters

xy	Contains the Cartesian coordinates to inverse.

Returns: An error code.

Reimplemented from IlvProjection.

§ getLatitudeOfTrueScale()

IlDouble IlvMercatorProjection::getLatitudeOfTrueScale ( ) const

Returns the latitude of the true scale in radian.

Returns: The latitude of the true scale.

§ setEllipsoid()

virtual IlvMapsError IlvMercatorProjection::setEllipsoid ( const IlvEllipsoid & ellipsoid )

virtual

Sets the ellipsoid used for the projection.

This virtual member function sets the ellipsoid used for the projection. Most of the projections are initialized with a spherical ellipsoid with a radius of 6,370,997 meters.

This function returns IlvMaps::NoError() if the operation is successful or an error status if you specify a non spherical ellipsoid and your type does not support non spherical.

Parameters

ellipsoid The ellipsoid used for the projection.

Returns: IlvMapsError if the ellipsoid does not match the projection.

Reimplemented from IlvProjection.

§ setLatitudeOfTrueScale()

void IlvMercatorProjection::setLatitudeOfTrueScale ( IlDouble latitudeOfTrueScale )

Sets the latitude of the true scale in radian.

Parameters

latitudeOfTrueScale The latitude of the true scale.

§ sForward()

virtual IlvMapsError IlvMercatorProjection::sForward ( IlvCoordinate & ll ) const

protectedvirtual

Must be redefined in subclasses to implement the projection for a sphere.

Parameters

ll	Contains the longitude and latitude coordinates in radian (x = longitude, y = latitude).

Returns: An error code.

Implements IlvProjection.

§ sInverse()

virtual IlvMapsError IlvMercatorProjection::sInverse ( IlvCoordinate & xy ) const

protectedvirtual

Must be redefined in subclasses to implement the inverse projection for a sphere.

The default implementation returns IlvProjection::UnsupportedFeatureError().

Parameters

xy	Contains the Cartesian coordinates to inverse.

Returns: An error code.

Reimplemented from IlvProjection.

§ write()

virtual void IlvMercatorProjection::write ( IlvOutputFile & outputFile ) const

virtual

Saves the parameters of a projection to the specified output file.

It must be overridden by subclasses of IlvProjection that need to save additional parameters.

This function should not be directly called; use the save() function instead.

Parameters

outputFile The file to write the projection parameters to.

Reimplemented from IlvProjection.

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

§ IlvMercatorProjection()

Member Function Documentation

§ eForward()

§ eInverse()

§ getLatitudeOfTrueScale()

§ setEllipsoid()

§ setLatitudeOfTrueScale()

§ sForward()

§ sInverse()

§ write()