IlvMapInfo Class Reference

The IlvMapInfo class is used to attach map information to an IlvManager. More...

#include <ilviews/maps/mapinfo.h>

List of all members.

Public Member Functions
	IlvMapInfo (const IlvProjection *projection, const IlvMapAdapter *adapter=0, IlBoolean copy=IlTrue)
	Initializes a new instance of IlvMapInfo.
IlvMapInfo *	attach (IlvManager *)
	Attaches the map information to manager. The map information will be automatically saved with the manager. This method returns the instance of IlvMapInfo that was previously attached to the manager or 0 if none. It also notifies the listeners that have been attached to the manager by the AddMapInfoListener() static method. .
void	detach ()
	Detaches map information from its manager and notifies the listeners of the manager.
IlvMapsError	forward (const IlvCoordinate &coord, IlvPoint &point) const
	Converts a latitude and a longitude into graphic coordinates.
const IlvMapAdapter *	getAdapter () const
	Returns the adapter of the map information.
IlvManager *	getManager () const
	Returns the manager that this map info is attached to.
const IlvProjection *	getProjection () const
	Returns the projection of the map information.
IlDouble	getScale (IlvView *view) const
	Returns the cartographic scale of the view.
const IlvUnitConverter *	getUnitConverter () const
	Returns the unit converter of the map information.
IlvMapsError	inverse (const IlvEvent &event, const IlvView *view, IlvCoordinate &coord) const
	Computes the longitude and latitude of the mouse event event that occurred in view. The result is stored in coord. .
IlvMapsError	inverse (const IlvPoint &point, IlvCoordinate &coord) const
	Converts graphic coordinates into geographic coordinates.
void	setScale (IlvView *view, IlDouble scale, IlBoolean redraw=IlTrue) const
	Sets the scale of view to scale. In the following example scale is set to 1/50,000th. .
IlvMapsError	toViews (const IlvCoordinate &data, const IlvProjection *sourceProjection, IlvPoint &result) const
	Converts a coordinate expressed in a source projection into the manager coordinate system, after having applied the projection of the map info.
Static Public Member Functions
static void	AddMapInfoListener (IlvManager *manager, IlvMapInfoListener *listener)
	Registers listener so that it can be notified about map information changes occurring to manager.
static IlvMapInfo *	Get (IlvManager *manager)
	Returns the map information that is attached to the specified manager.
static void	RemoveMapInfoListener (IlvManager *manager, IlvMapInfoListener *listener)
	Removes specified listener to the notification list of the specified manager.
static void	SetScreenSize (IlvDisplay *display, IlUInt heightmm, IlUInt widthmm)
	Specifies the height and the width of the display screen for a more accurate scale management.

---

Detailed Description

The IlvMapInfo class is used to attach map information to an IlvManager.

This class is used to attach map information to an IlvManager.
This information is persistent and is automatically saved when the manager is saved.
When an IlvMapInfo is attached to an IlvManager, the manager becomes georeferenced. The points of the manager can be interpreted in terms of distances. Heterogeneous map data can be potentially loaded into the manager because the Cartesian coordinate system of the manager (specified by a projection) is known.
In addition to enabling applications to save georeferencing information, the IlvMapInfo class provides additional services, such as directly converting latitude and longitude into points expressed in the manager coordinate system, converting mouse events into latitude and longitude, or setting the scale of a view.
Library: ilvmaps

See also:

IlvMapAdapter, IlvProjection, IlvUnitConverter, IlvMapInfoListener.

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Constructor & Destructor Documentation

IlvMapInfo::IlvMapInfo	(	const IlvProjection *	projection,
		const IlvMapAdapter *	adapter = 0,
		IlBoolean	copy = IlTrue
	)

Initializes a new instance of IlvMapInfo.

Initializes an IlvMapInfo with projection and adapter.

Parameters:

	projection	The projection to be attached.
	adapter	The adapter for this projection. If this parameter is not specified, a new IlvMapAdapter optimized for the projection is used.
	copy	If IlTrue, the arguments projection and adapter are copied. If not specified, defaults to IlTrue.

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Member Function Documentation

static void IlvMapInfo::AddMapInfoListener	(	IlvManager *	manager,
		IlvMapInfoListener *	listener
	)			[static]

Registers listener so that it can be notified about map information changes occurring to manager.

Parameters:

	manager	The manager to listen to.
	listener	The listener to register.

IlvMapInfo* IlvMapInfo::attach

(

IlvManager *

)

Attaches the map information to manager. The map information will be automatically saved with the manager.
This method returns the instance of IlvMapInfo that was previously attached to the manager or 0 if none. It also notifies the listeners that have been attached to the manager by the AddMapInfoListener() static method.
.

Warning:

When map information is attached to a manager, the manager becomes the owner of the map information, and will delete it in its destructor.

Parameters:

manager

The manager this map info is attached to.

Returns:

The previously attached map info, if any.

IlvMapsError IlvMapInfo::forward	(	const IlvCoordinate &	coord,
		IlvPoint &	point
	)			const

Converts a latitude and a longitude into graphic coordinates.

This member function is a convenience function that first calls the forward() function of the projection of the map information, and then the toViews() function of the adapter.

Parameters:

	coord	The geographic coordinates to be converted.
	point	Stores the graphic coordinates of the point.

Returns:

The error code returned by IlvProjection::forward().

static IlvMapInfo* IlvMapInfo::Get

(

IlvManager *

manager

)

[static]

Returns the map information that is attached to the specified manager.

This static function is a convenience function that returns the instance of IlvMapInfo that is attached to manager, or a null pointer if no map information is attached to it.

Parameters:

manager

The manager which map information is to be returned.

Returns:

The attached IlvMapInfo.

const IlvMapAdapter* IlvMapInfo::getAdapter

(

)

const

Returns the adapter of the map information.

The adapter is used to convert coordinates expressed in the geographic Cartesian coordinate system (that is, projected latitude and longitude) into points in a manager coordinate system.

Returns:

The adapter of the map information.

IlvManager* IlvMapInfo::getManager

(

)

const

Returns the manager that this map info is attached to.

Returns:

The manager to which the map information is attached or a null pointer if the map is not attached to any manager.

const IlvProjection* IlvMapInfo::getProjection

(

)

const

Returns the projection of the map information.

The projection is used to convert latitude and longitude into a Cartesian coordinate system.

Returns:

The projection of the map information.

IlDouble IlvMapInfo::getScale

(

IlvView *

view

)

const

Returns the cartographic scale of the view.

The scale is the ratio between the size of the objects drawn in view and the size of these objects in the geographic Cartesian coordinate system, which could be called the real size of these objects.

Warning:

[note] The computation of the scale depends on the size of the screen where view is displayed. The getScale method tries to determine this size, but the platform API to get this size often returns inaccurate results. For a more precise scale management, you can specify the size of the screen using the SetScreenSize() static function.

Parameters:

view

The view for which the scale is to be computed.

Returns:

The scale of the view.

const IlvUnitConverter* IlvMapInfo::getUnitConverter

(

)

const

Returns the unit converter of the map information.

The unit converter is used to convert distances in the geographic Cartesian coordinate system into meters.

Returns:

The unit converter of the map information.

IlvMapsError IlvMapInfo::inverse	(	const IlvEvent &	event,
		const IlvView *	view,
		IlvCoordinate &	coord
	)			const

Computes the longitude and latitude of the mouse event event that occurred in view. The result is stored in coord.
.

Warning:

This function should not be called if the instance of IlvMapInfo is not attached to the manager of the view.

Parameters:

	event	The mouse event.
	view	The view in which the event occurred.
	coord	Stores the result of the computation.

Returns:

The error code returned by IlvProjection::inverse().

IlvMapsError IlvMapInfo::inverse	(	const IlvPoint &	point,
		IlvCoordinate &	coord
	)			const

Converts graphic coordinates into geographic coordinates.

This member function is a convenience function that calls first the fromViews() function of the adapter of the map information, and then the inverse() function of the projection.

Parameters:

	point	The graphic coordinates to be converted.
	coord	Stores the geographic coordinates of the point.

Returns:

The error code returned by IlvProjection::inverse().

static void IlvMapInfo::RemoveMapInfoListener	(	IlvManager *	manager,
		IlvMapInfoListener *	listener
	)			[static]

Removes specified listener to the notification list of the specified manager.

Removes listener from the list of listeners that will be notified about the map information changes that occur to manager.

Parameters:

	manager	The target manager.
	listener	The listener to be removed.

void IlvMapInfo::setScale	(	IlvView *	view,
		IlDouble	scale,
		IlBoolean	redraw = IlTrue
	)			const

Sets the scale of view to scale. In the following example scale is set to 1/50,000^th.
.

 mapInfo->setScale(view,
                   1. / 50000.,
                   IlTrue);

Parameters:

	view	The view which scale is to be set.
	scale	The scale to be set.
	redraw	If IlTrue, an immediate refresh of the view is performed. If IlFalse, this method only affects the transformer of the view. If not specified, this defaults to IlTrue.

static void IlvMapInfo::SetScreenSize	(	IlvDisplay *	display,
		IlUInt	heightmm,
		IlUInt	widthmm
	)			[static]

Specifies the height and the width of the display screen for a more accurate scale management.

heightmm and widthmm must be expressed in millimeters.

Parameters:

	display	The display screen.
	heightmm	The height of the screen, in millimeters.
	widthmm	The width of the screen, in millimeters.

IlvMapsError IlvMapInfo::toViews	(	const IlvCoordinate &	data,
		const IlvProjection *	sourceProjection,
		IlvPoint &	result
	)			const

Converts a coordinate expressed in a source projection into the manager coordinate system, after having applied the projection of the map info.

Parameters:

	data	The coordinate to be translated, expressed in the source projection.
	sourceProjection	The projection of data. If this parameter is set to 0, the function assumes that data is expressed in the mapinfo projection.
	result	Stores the result of the translation.

Returns:

The error code returned by projection conversion functions.