A curved line from one point to another. More...

#include <plot2d.h>

Inheritance diagram for QCPItemCurve:

Public Member Functions
	QCPItemCurve (QCustomPlot *parentPlot)

virtual	~QCPItemCurve ()

QPen	pen () const

QPen	selectedPen () const

QCPLineEnding	head () const

QCPLineEnding	tail () const

void	setPen (const QPen &pen)

void	setSelectedPen (const QPen &pen)

void	setHead (const QCPLineEnding &head)

void	setTail (const QCPLineEnding &tail)

virtual double	selectTest (const QPointF &pos) const

Public Member Functions inherited from QCPAbstractItem
	QCPAbstractItem (QCustomPlot *parentPlot)

virtual	~QCPAbstractItem ()

bool	clipToAxisRect () const

QCPAxis *	clipKeyAxis () const

QCPAxis *	clipValueAxis () const

bool	selectable () const

bool	selected () const

void	setClipToAxisRect (bool clip)

void	setClipAxes (QCPAxis keyAxis, QCPAxis valueAxis)

void	setClipKeyAxis (QCPAxis *axis)

void	setClipValueAxis (QCPAxis *axis)

void	setSelectable (bool selectable)

void	setSelected (bool selected)

QList< QCPItemPosition * >	positions () const

QList< QCPItemAnchor * >	anchors () const

QCPItemPosition *	position (const QString &name) const

QCPItemAnchor *	anchor (const QString &name) const

bool	hasAnchor (const QString &name) const

Public Member Functions inherited from QCPLayerable
	QCPLayerable (QCustomPlot *parentPlot)

	~QCPLayerable ()

bool	visible () const

QCustomPlot *	parentPlot () const

QCPLayer *	layer () const

bool	antialiased () const

void	setVisible (bool on)

bool	setLayer (QCPLayer *layer)

bool	setLayer (const QString &layerName)

void	setAntialiased (bool enabled)

Public Attributes
QCPItemPosition *const	start

QCPItemPosition *const	startDir

QCPItemPosition *const	endDir

QCPItemPosition *const	end

Protected Member Functions
virtual void	draw (QCPPainter *painter)

QPen	mainPen () const

Protected Member Functions inherited from QCPAbstractItem
virtual QRect	clipRect () const

virtual void	applyDefaultAntialiasingHint (QCPPainter *painter) const

double	distSqrToLine (const QPointF &start, const QPointF &end, const QPointF &point) const

double	rectSelectTest (const QRectF &rect, const QPointF &pos, bool filledRect) const

virtual QPointF	anchorPixelPoint (int anchorId) const

QCPItemPosition *	createPosition (const QString &name)

QCPItemAnchor *	createAnchor (const QString &name, int anchorId)

Protected Member Functions inherited from QCPLayerable
bool	moveToLayer (QCPLayer *layer, bool prepend)

void	applyAntialiasingHint (QCPPainter *painter, bool localAntialiased, QCP::AntialiasedElement overrideElement) const

Protected Attributes
QPen	mPen

QPen	mSelectedPen

QCPLineEnding	mHead

QCPLineEnding	mTail

Protected Attributes inherited from QCPAbstractItem
bool	mClipToAxisRect

QCPAxis *	mClipKeyAxis

QCPAxis *	mClipValueAxis

bool	mSelectable

bool	mSelected

QList< QCPItemPosition * >	mPositions

QList< QCPItemAnchor * >	mAnchors

Protected Attributes inherited from QCPLayerable
bool	mVisible

QCustomPlot *	mParentPlot

QCPLayer *	mLayer

bool	mAntialiased

Additional Inherited Members
Signals inherited from QCPAbstractItem
void	selectionChanged (bool selected)

Detailed Description

A curved line from one point to another.

Curve example. Blue dotted circles are anchors, solid blue discs are positions.

It has four positions, start and end, which define the end points of the line, and two control points which define the direction the line exits from the start and the direction from which it approaches the end: startDir and endDir.

With setHead and setTail you may set different line ending styles, e.g. to create an arrow.

Often it is desirable for the control points to stay at fixed relative positions to the start/end point. This can be achieved by setting the parent anchor e.g. of startDir simply to start, and then specify the desired pixel offset with QCPItemPosition::setCoords on startDir.

Constructor & Destructor Documentation

QCPItemCurve::QCPItemCurve ( QCustomPlot * parentPlot )

Creates a curve item and sets default values.

The constructed item can be added to the plot with QCustomPlot::addItem.

QCPItemCurve::~QCPItemCurve ( )

virtual

Member Function Documentation

void QCPItemCurve::draw ( QCPPainter * painter )

protectedvirtual

Implements QCPAbstractItem.

QCPLineEnding QCPItemCurve::head ( ) const

inline

QPen QCPItemCurve::mainPen ( ) const

protected

QPen QCPItemCurve::pen ( ) const

inline

QPen QCPItemCurve::selectedPen ( ) const

inline

double QCPItemCurve::selectTest ( const QPointF & pos ) const

virtual

This function is used to decide whether a click hits an item or not.

pos is a point in pixel coordinates on the QCustomPlot surface. This function returns the shortest pixel distance of this point to the item. If the item is either invisible or the distance couldn't be determined, -1.0 is returned. setSelectable has no influence on the return value of this function.

If the item is represented not by single lines but by an area like QCPItemRect or QCPItemText, a click inside the area returns a constant value greater zero (typically 99% of the selectionTolerance of the parent QCustomPlot). If the click lies outside the area, this function returns -1.0.

Providing a constant value for area objects allows selecting line objects even when they are obscured by such area objects, by clicking close to the lines (i.e. closer than 0.99*selectionTolerance).

The actual setting of the selection state is not done by this function. This is handled by the parent QCustomPlot when the mouseReleaseEvent occurs.