IlvPieChartGraphic Class Reference

Implementation of predefined pie charts. More...

#include <ilviews/charts/simplegr.h>

Inheritance diagram for IlvPieChartGraphic:

List of all members.

Public Member Functions
	IlvPieChartGraphic (IlvDisplay *display, const IlvRect &bbox, IlDouble startingAngle=0., IlDouble range=360., IlDouble centerRatio=0., IlvPalette *palette=0)
	Constructor.
IlvPieChartDisplayer *	addPieDisplayer (IlvChartDataSet *dataSet, IlDouble radiusRatio=1., IlvPalette *palette=0)
	Creates and adds a pie displayer.
virtual void	draw (IlvPort *dst, const IlvTransformer *t=0, const IlvRegion *givenClip=0) const
	Draws the current object.
IlDouble	getCenterRatio () const
	Returns the ratio of the center part relative to the data display area.
IlvPieChartDisplayer *	getPieDisplayer (IlUInt index) const
	Returns a given pie displayer.
IlDouble	getRange () const
	Returns the range of the pie(s).
IlDouble	getStartingAngle () const
	Returns the angle at which the first slice of the pie(s) is drawn.
IlBoolean	isUsingAutoRadius () const
	Indicates whether the radius of the pie(s) is automatically computed.
void	setCenterRatio (IlDouble ratio)
	Sets the ratio of the center part relative to the data display area.
void	setRange (IlDouble range)
	Sets the angle range of the pie(s).
void	setStartingAngle (IlDouble angle)
	Sets the angle at which the first slice of the pie(s) is drawn.
void	useAutoRadius (IlBoolean b)
	Specifies whether the radius of the pie(s) is automatically computed.
Protected Member Functions
virtual IlvPieChartDisplayer *	createPieDisplayer (IlDouble radiusRatio, IlDouble startingAngle, IlDouble range) const
	Creates a new pie displayer.

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Detailed Description

Implementation of predefined pie charts.

Library: ilvcharts

This class is a subclass of IlvPolarChart which allows you to display a chart made of one or several pies centered on the same point.

The pies centered on the same point can be displayed with a center part as you can see on the left in the image below. The center part is made of a circle drawn with the foreground color of the palette of the chart and filled with the background color of the palette of the chart.

Two examples of pie charts are shown below. The pie chart on the left is made of two pies (displayed by two pie displayers) and a center part. The pie chart on the right is made of only one pie (displayed by a pie displayer).

See also:

IlvPolarChart.

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Constructor & Destructor Documentation

IlvPieChartGraphic::IlvPieChartGraphic	(	IlvDisplay *	display,
		const IlvRect &	bbox,
		IlDouble	startingAngle = 0.,
		IlDouble	range = 360.,
		IlDouble	centerRatio = 0.,
		IlvPalette *	palette = 0
	)

Constructor.

Initializes a new IlvPieChartGraphic object. The flag indicating whether the radius of the pie(s) is automatically computed is set to IlTrue by default.

Parameters:

	display	The display connection that will handle the drawing of this object.
	bbox	The initial bounding box of the chart graphic.
	startingAngle	The angle at which the first slice of the pie(s) will be drawn.
	range	The angle range covered by the slices of the pie(s).
	centerRatio	The ratio of the center part relative to the data display area. This value must be between 0 and 1. If it is equal to 0, no center part will be drawn.
	palette	The palette associated with the chart.

Warning:

[note] No pie displayer is added by default. To add the pie displayers you want to be used by this object, you should use the IlvPieChartGraphic::addPieDisplayer method.

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Member Function Documentation

IlvPieChartDisplayer* IlvPieChartGraphic::addPieDisplayer	(	IlvChartDataSet *	dataSet,
		IlDouble	radiusRatio = 1.,
		IlvPalette *	palette = 0
	)

Creates and adds a pie displayer.

The pie displayer that is added is created inside this method by calling the IlvPieChartGraphic::createPieDisplayer method.

Parameters:

	dataSet	The data set that will be displayed by the new pie displayer.
	radiusRatio	The ratio of the radius of the pie relative to the ordinate range of the chart graphic. This value must be between 0 and 1. This value will be taken into account only if the flag indicating whether the radius of the pie(s) is automatically computed is equal to IlFalse.
	palette	The palette that will be used by the pie displayer.

Returns:

A pointer to the pie displayer that has been created.

Warning:

[note] If the flag indicating whether the radius of the pie(s) is automatically computed is equal to IlTrue (see the method IlvPieChartGraphic::isUsingAutoRadius), the radius of all the pie displayers that are defined is automatically recomputed. The radius are recomputed so that the visible portion of the pies takes all the available space in the data display area once the space taken by the center part has been removed and so that the visible portion of the pies has the same width.

virtual IlvPieChartDisplayer* IlvPieChartGraphic::createPieDisplayer	(	IlDouble	radiusRatio,
		IlDouble	startingAngle,
		IlDouble	range
	)			const [protected, virtual]

Creates a new pie displayer.

Parameters:

	radiusRatio	The ratio of the radius of the pie relative to the ordinate range of the chart graphic. This value must be between 0 and 1.
	startingAngle	The angle at which the first slice will be drawn for the pie.
	range	The angle range of the pie.

Warning:

[note] This method is used internally and should not be used directly by the user. It is called in the IlvPieChartGraphic::addPieDisplayer method to create the pie displayer that is added to the current object.

virtual void IlvPieChartGraphic::draw	(	IlvPort *	dst,
		const IlvTransformer *	t = 0,
		const IlvRegion *	givenClip = 0
	)			const [virtual]

Draws the current object.

The current implementation of the method calls the IlvPolarChart::draw method to draw the chart graphic (including all the pie displayers that have been added) and then draws the center part if the center ratio is different from 0. The center part is made of a circle drawn with the foreground color of the palette of the chart and filled with the background color of the palette of the chart. The drawing is performed in the port dst using the transformer t and the clipping region clip.

Parameters:

	dst	The port used for the drawing.
	t	The optional transformer.
	clip	The optional clipping region.

Reimplemented from IlvChartGraphic.

IlDouble IlvPieChartGraphic::getCenterRatio

(

)

const

Returns the ratio of the center part relative to the data display area.

Returns:

The ratio of the center part relative to the data display area.

IlvPieChartDisplayer* IlvPieChartGraphic::getPieDisplayer

(

IlUInt

index

)

const

Returns a given pie displayer.

Parameters:

index

The index of a pie displayer that has been added to the current object.

Returns:

A pointer to the pie displayer with the index index that has been added to the current object.

IlDouble IlvPieChartGraphic::getRange

(

)

const

Returns the range of the pie(s).

Returns:

The angle range of the pie(s).

See also:

setRange.

IlDouble IlvPieChartGraphic::getStartingAngle

(

)

const

Returns the angle at which the first slice of the pie(s) is drawn.

Returns:

The angle at which the first slice of the pie(s) is drawn.

See also:

setStartingAngle.

IlBoolean IlvPieChartGraphic::isUsingAutoRadius

(

)

const

Indicates whether the radius of the pie(s) is automatically computed.

Returns:

IlTrue if the radius of the pie(s) is automatically computed and IlFalse otherwise.

void IlvPieChartGraphic::setCenterRatio

(

IlDouble

ratio

)

Sets the ratio of the center part relative to the data display area.

Parameters:

ratio

The new ratio of the center part relative to the data display area. This value must be between 0 and 1.

void IlvPieChartGraphic::setRange

(

IlDouble

range

)

Sets the angle range of the pie(s).

This range corresponds to the sum of the angles of the slices. If range is equal to 360 degrees, the slices will cover a whole circle.

Parameters:

range

The new angle range of the pie(s). The angle range must be expressed in degrees.

void IlvPieChartGraphic::setStartingAngle

(

IlDouble

angle

)

Sets the angle at which the first slice of the pie(s) is drawn.

Warning:

[note] This angle must be expressed in degrees.

Parameters:

angle

The new angle at which the first slice of the pie(s) is drawn.

void IlvPieChartGraphic::useAutoRadius

(

IlBoolean

b

)

Specifies whether the radius of the pie(s) is automatically computed.

Parameters:

b

The new value of the Boolean indicating whether the radius of the pie(s) is automatically computed.