A figure container for organizing Qwt plots with flexible layout options 更多...

#include <qwt_figure.h>

类 QwtFigure 继承关系图:

类
class	PrivateData

信号
void	axesAdded (QwtPlot *newAxes)
	Signal emitted when axes are added to the figure

void	axesRemoved (QwtPlot *removedAxes)
	Signal emitted when axes are removed from the figure

void	figureCleared ()
	Signal emitted when the figure is cleared

void	currentAxesChanged (QwtPlot *current)
	Signal emitted when the current active axes changes

Public 成员函数
	QwtFigure (QWidget *parent=nullptr, Qt::WindowFlags f=Qt::WindowFlags())
	Constructor

void	addWidget (QWidget *widget, qreal left, qreal top, qreal width, qreal height)
	Add a widget with normalized coordinates

void	addWidget (QWidget *widget, int rowCnt, int colCnt, int row, int col, int rowSpan=1, int colSpan=1, qreal wspace=0.0, qreal hspace=0.0)
	Add a widget by grid layout

void	addAxes (QwtPlot *plot, const QRectF &rect)
	Add a plot with normalized coordinates

void	addAxes (QwtPlot *plot, qreal left, qreal top, qreal width, qreal height)
	Add a plot with normalized coordinates using separate parameters

void	addGridAxes (QwtPlot *plot, int rowCnt, int colCnt, int row, int col, int rowSpan=1, int colSpan=1, qreal wspace=0.0, qreal hspace=0.0)
	Add a plot by grid layout

void	setWidgetNormPos (QWidget *widget, const QRectF &rect)
	Change the normalized position of an already added widget. If the widget hasn't been added yet, this function has no effect.

QList< QwtPlot * >	allAxes (bool byZOrder=false) const
	Get all axes (plots) in the figure (not including parasite axes)

bool	hasAxes () const
	Check if the figure has any axes

bool	hasAxes (QwtPlot *plot) const
	Check if the figure contains a specific plot

void	removeAxes (QwtPlot *plot)
	Remove a specific axes (plot) from the figure

bool	takeAxes (QwtPlot *plot)
	Take a specific axes (plot) from the figure without deleting it

void	clear ()
	Clear all axes from the figure

QSize	getSizeInches () const
	Get the size of the figure in inches

void	setSizeInches (float width, float height)
	Set the size of the figure in inches

void	setSizeInches (const QSizeF &size)
	Set the size of the figure in inches

void	setFaceColor (const QColor &color)
	Set the face color of the figure

QColor	faceColor () const
	Get the face color of the figure

void	setFaceBrush (const QBrush &brush)
	Set the face brush of the figure

QBrush	faceBrush () const
	Get the face brush of the figure

void	setEdgeColor (const QColor &color)
	Set the edge color of the figure

QColor	edgeColor () const
	Get the edge color of the figure

void	setEdgeLineWidth (int width)
	Set the edge line width of the figure

int	edgeLineWidth () const
	Get the edge line width of the figure

QwtPlot *	createParasiteAxes (QwtPlot *hostPlot, QwtAxis::Position enableAxis)
	Create parasite axes for a host plot

QList< QwtPlot * >	getParasiteAxes (QwtPlot *hostPlot) const
	Get all parasite axes for a host plot

QPixmap	saveFig (int dpi=-1) const
	Save the figure to a QPixmap with specified DPI

QPixmap	saveFig (QSizeF &inchesSize) const
	Save the figure to a QPixmap with specified size in inches

bool	saveFig (const QString &filename, int dpi=-1) const
	Save the figure to a file with specified DPI

void	setCurrentAxes (QwtPlot *plot)
	Set the current axes (plot)

void	sca (QwtPlot *plot)
	Set the current axes (plot)

QwtPlot *	currentAxes () const
	Get the current axes (plot)

QwtPlot *	gca () const
	Get the current axes (plot)

QRectF	axesNormRect (QwtPlot *plot) const
	Get the normalized rectangle for a axes

QRectF	widgetNormRect (QWidget *w) const
	Get the normalized rectangle for a widget

QwtPlot *	plotUnderPos (const QPoint &pos) const
	Get the plot under a position

QRectF	calcNormRect (const QRect &geoRect) const
	Calculate normalized coordinates from actual window coordinates

QRect	calcActualRect (const QRectF &normRect)
	Calculate actual rectangle from normalized coordinates

void	replotAll ()
	Update all plots in the figure

void	addAxisAlignment (const QList< QwtPlot * > &plots, int axisId)
	Add axis alignment configuration

bool	removeAxisAlignment (const QList< QwtPlot * > &plots, int axisId)
	Remove specified axis alignment configuration

void	clearAxisAlignment ()
	Clear all axis alignment configurations

void	applyAllAxisAlignments (bool replot=true)
	Apply all axis alignment configurations

void	applyAlignmentsForAxis (int axisId)
	Apply alignment configurations for a specific axis

int	axisAligmentCount () const
	Get the number of axis alignment configurations

QPair< QList< QwtPlot * >, int >	axisAligmentInfo (int index) const
	Get axis alignment information by index

静态 Public 成员函数
static void	alignAxes (QList< QwtPlot * > plots, int axisId, bool update=true)
	Align axes of multiple plots

Protected 成员函数
void	paintEvent (QPaintEvent *event) override

void	resizeEvent (QResizeEvent *event) override

详细描述

A figure container for organizing Qwt plots with flexible layout options

This class provides a figure-like container similar to matplotlib's Figure class, supporting both normalized coordinate positioning and grid layouts for Qwt plots. It uses Qt's standard top-left coordinate system for intuitive positioning.

Example:: // Example usage:

QwtFigure figure;

// Add a plot using normalized coordinates (Qt top-left coordinate system)

QwtPlot* plot1 = new QwtPlot;

figure.addAxes(plot1, QRectF(0.1, 0.1, 0.8, 0.4));

// Add plots using grid layout - Create a 2x2 grid

QwtPlot* plot2 = new QwtPlot;

figure.addAxes(plot2, 2, 2, 0, 1); // 2x2 grid, row 0, column 1

QwtPlot* plot3 = new QwtPlot;

figure.addAxes(plot3, 2, 2, 1, 0, 1, 2); // row 1, columns 0-1 (span 2 columns)

// Save the figure

figure.saveFig("output.png", 300);

QwtFigure
A figure container for organizing Qwt plots with flexible layout options
Definition qwt_figure.h:47

QwtFigure::saveFig
QPixmap saveFig(int dpi=-1) const
Save the figure to a QPixmap with specified DPI
Definition qwt_figure.cpp:602

QwtFigure::addAxes
void addAxes(QwtPlot *plot, const QRectF &rect)
Add a plot with normalized coordinates
Definition qwt_figure.cpp:151

QwtPlot
A 2-D plotting widget
Definition qwt_plot.h:99

构造及析构函数说明

◆ QwtFigure()

QwtFigure::QwtFigure	(	QWidget *	parent = `nullptr`,
		Qt::WindowFlags	f = `Qt::WindowFlags()`
	)

Constructor

参数

parent	Parent widget
f	Window flags

成员函数说明

◆ addAxes() [1/2]

void QwtFigure::addAxes	(	QwtPlot *	plot,
		const QRectF &	rect
	)

Add a plot with normalized coordinates

This method adds a QwtPlot to the figure using normalized coordinates in the range [0,1]. The coordinates are specified as [left, bottom, width, height].

参数

plot	QwtPlot to add
rect	Normalized coordinates [left, bottom, width, height] in range [0,1]

注解: This function will emit axesAdded signal, followed by currentAxesChanged signal

◆ addAxes() [2/2]

void QwtFigure::addAxes	(	QwtPlot *	plot,
		qreal	left,
		qreal	top,
		qreal	width,
		qreal	height
	)

Add a plot with normalized coordinates using separate parameters

参数

plot	QwtPlot to add
left	Normalized coordinates left in range [0,1]
top	Normalized coordinates top in range [0,1]
width	Normalized coordinates width in range [0,1]
height	Normalized coordinates height in range [0,1]

注解: This function will emit axesAdded signal, followed by currentAxesChanged signal

◆ addAxisAlignment()

void QwtFigure::addAxisAlignment	(	const QList< QwtPlot * > &	plots,
		int	axisId
	)

Add axis alignment configuration

This method adds an alignment configuration for the specified plots and axis.

参数

plots	List of plots to align
axisId	Axis ID to align (QwtAxis::XTop/XBottom/YLeft/YRight)

◆ addGridAxes()

void QwtFigure::addGridAxes	(	QwtPlot *	plot,
		int	rowCnt,
		int	colCnt,
		int	row,
		int	col,
		int	rowSpan = `1`,
		int	colSpan = `1`,
		qreal	wspace = `0.0`,
		qreal	hspace = `0.0`
	)

Add a plot by grid layout

This method adds a QwtPlot to the grid layout at the specified position with optional row and column spans.

参数

plot	QwtPlot to add
rowCnt	Number of rows in the grid
colCnt	Number of columns in the grid
row	Grid row position (0-based)
col	Grid column position (0-based)
rowSpan	Number of rows to span (default: 1)
colSpan	Number of columns to span (default: 1)
wspace	Horizontal space between subplots [0,1]
hspace	Vertical space between subplots [0,1]

注解: This function will emit axesAdded signal, followed by currentAxesChanged signal

◆ addWidget() [1/2]

void QwtFigure::addWidget	(	QWidget *	widget,
		int	rowCnt,
		int	colCnt,
		int	row,
		int	col,
		int	rowSpan = `1`,
		int	colSpan = `1`,
		qreal	wspace = `0.0`,
		qreal	hspace = `0.0`
	)

Add a widget by grid layout

This method adds a widget to the grid layout at the specified position with optional row and column spans.

参数

widget	Widget to add
rowCnt	Number of rows in the grid
colCnt	Number of columns in the grid
row	Grid row position (0-based)
col	Grid column position (0-based)
rowSpan	Number of rows to span (default: 1)
colSpan	Number of columns to span (default: 1)
wspace	Horizontal space between subplots [0,1]
hspace	Vertical space between subplots [0,1]

注解: Even if the added widget is a QwtPlot, this function will not emit axesAdded signal. Use addAxes() instead if you need to add QwtPlot widgets.

参见: addAxes

◆ addWidget() [2/2]

void QwtFigure::addWidget	(	QWidget *	widget,
		qreal	left,
		qreal	top,
		qreal	width,
		qreal	height
	)

Add a widget with normalized coordinates

参数

widget	QWidget to add
left	Normalized coordinates left in range [0,1]
top	Normalized coordinates top in range [0,1]
width	Normalized coordinates width in range [0,1]
height	Normalized coordinates height in range [0,1]

注解: Even if the added widget is a QwtPlot, this function will not emit axesAdded signal. Use addAxes() instead if you need to add QwtPlot widgets.

参见: addAxes

◆ alignAxes()

void QwtFigure::alignAxes	(	QList< QwtPlot * >	plots,
		int	axisId,
		bool	update = `true`
	)

static

Align axes of multiple plots

This function unifies the minimumExtent and minBorderDist of the specified axis to ensure visual alignment of axes.

参数

plots	List of QwtPlot to align (must be non-empty)
axisId	Axis ID to align (QwtAxis::XTop/XBottom/YLeft/YRight)
replot	If true, update layout and replot after alignment

注解: This function should be called after widget initialization (e.g., in showEvent/resizeEvent).; Supports any number of plots and any valid axis type, adapting to horizontal/vertical layouts.; Do not pass parasite axes, currently only supports host axes.

◆ allAxes()

QList< QwtPlot * > QwtFigure::allAxes ( bool byZOrder = false ) const

Get all axes (plots) in the figure (not including parasite axes)

This method returns a list of all QwtPlot objects added to the figure.

参数

byZOrder If true, sort by z-order from top to bottom

返回: List of all QwtPlot objects (not including parasite axes)

注解: Parasite axes are not included in the returned list

◆ applyAlignmentsForAxis()

void QwtFigure::applyAlignmentsForAxis ( int axisId )

Apply alignment configurations for a specific axis

This method applies all alignment configurations for the specified axis ID.

参数

axisId Axis ID to apply alignments for

◆ applyAllAxisAlignments()

void QwtFigure::applyAllAxisAlignments ( bool replot = true )

Apply all axis alignment configurations

This method applies all recorded alignment configurations to the plots.

参数

replot If true, replot all affected plots after alignment

◆ axesAdded

void QwtFigure::axesAdded ( QwtPlot * newAxes )

signal

Signal emitted when axes are added to the figure

参数

newAxes Pointer to the newly added QwtPlot

注解: Parasite axes addition also triggers this signal

◆ axesNormRect()

QRectF QwtFigure::axesNormRect ( QwtPlot * plot ) const

Get the normalized rectangle for a axes

This method returns the normalized coordinates [0,1] for the specified axes in the figure. If the axes is not found in the figure, an invalid QRectF is returned.

参数

widget Widget to query

返回: Normalized coordinates [left, top, width, height] in range [0,1], or invalid QRectF if not found

◆ axesRemoved

void QwtFigure::axesRemoved ( QwtPlot * removedAxes )

signal

Signal emitted when axes are removed from the figure

参数

removedAxes Pointer to the removed QwtPlot

注解: Parasite axes removal also triggers this signal

◆ axisAligmentCount()

int QwtFigure::axisAligmentCount ( ) const

Get the number of axis alignment configurations

This method returns the count of alignment configurations added via addAxisAlignment.

返回: Number of alignment configurations

◆ axisAligmentInfo()

QPair< QList< QwtPlot * >, int > QwtFigure::axisAligmentInfo ( int index ) const

Get axis alignment information by index

This method returns the alignment configuration at the specified index.

参数

index Index of the alignment configuration to retrieve

返回: QPair containing the plot list and axis ID

◆ calcActualRect()

QRect QwtFigure::calcActualRect ( const QRectF & normRect )

Calculate actual rectangle from normalized coordinates

This method converts normalized coordinates to actual window coordinates.

参数

normRect Normalized coordinates QRectF

返回: Actual window coordinates QRect

◆ calcNormRect()

QRectF QwtFigure::calcNormRect ( const QRect & geoRect ) const

Calculate normalized coordinates from actual window coordinates

This method converts actual window coordinates (geometry) to normalized coordinates.

参数

geoRect Actual window coordinates (geometry)

返回: Normalized coordinates QRectF

◆ clear()

void QwtFigure::clear ( )

Clear all axes from the figure

This method removes all QwtPlot objects from the figure and deletes them.

注解: This method emits axesRemoved signal during removal process.; After all removals, currentAxesChanged signal is emitted with nullptr, then figureCleared signal.; This method deletes all held plot widgets.

◆ clearAxisAlignment()

void QwtFigure::clearAxisAlignment ( )

Clear all axis alignment configurations

This method removes all alignment configurations from the figure.

◆ createParasiteAxes()

QwtPlot * QwtFigure::createParasiteAxes	(	QwtPlot *	hostPlot,
		QwtAxis::Position	enableAxis
	)

Create parasite axes for a host plot

This method creates a parasite axes that shares the same plotting area as the host plot but with independent axis scaling and labeling. The parasite axes will be positioned exactly on top of the host plot and will automatically synchronize its geometry.

参数

hostPlot	Pointer to the host QwtPlot
enableAxis	The axis position to enable on the parasite axes

返回: Pointer to the created parasite QwtPlot

返回值

nullptr if hostPlot is invalid or not in the figure

注解: The parasite axes will have a transparent background and only the specified axis will be visible.; The parasite axes will automatically be deleted when the host plot is removed from the figure.; Parasitic axes are not stored in QwtFigureLayout, but are separately controlled by QwtFigure for layout management.; Parasite axes must be managed by the figure because they only overlap the plotting area with the host, while the coordinate window positions are different from the host.

◆ currentAxes()

QwtPlot * QwtFigure::currentAxes ( ) const

Get the current axes (plot)

This method returns the current active QwtPlot in the figure. The current axes is typically the last axes that was added, modified, or plotted on.

返回: Pointer to the current QwtPlot, or nullptr if no axes exist

◆ currentAxesChanged

void QwtFigure::currentAxesChanged ( QwtPlot * current )

signal

Signal emitted when the current active axes changes

参数

current Pointer to the current QwtPlot, nullptr if no valid axes

注解: Parasite axes cannot be set as current axes

◆ edgeColor()

QColor QwtFigure::edgeColor ( ) const

Get the edge color of the figure

This method returns the border color of the figure.

返回: Border color

◆ edgeLineWidth()

int QwtFigure::edgeLineWidth ( ) const

Get the edge line width of the figure

This method returns the border line width of the figure.

返回: Border line width in pixels

◆ faceBrush()

QBrush QwtFigure::faceBrush ( ) const

Get the face brush of the figure

This method returns the background brush of the figure.

返回: Background brush

◆ faceColor()

QColor QwtFigure::faceColor ( ) const

Get the face color of the figure

This method returns the background color of the figure.

返回: Background color

◆ gca()

QwtPlot * QwtFigure::gca ( ) const

Get the current axes (plot)

This is a convenience method that calls currentAxes.

返回: Pointer to the current QwtPlot, or nullptr if no axes exist

◆ getParasiteAxes()

QList< QwtPlot * > QwtFigure::getParasiteAxes ( QwtPlot * hostPlot ) const

Get all parasite axes for a host plot

This method returns a list of all parasite axes associated with the specified host plot.

参数

hostPlot Pointer to the host QwtPlot

返回: List of parasite QwtPlot pointers

返回值

Empty list if hostPlot is invalid or has no parasite axes

◆ getSizeInches()

QSize QwtFigure::getSizeInches ( ) const

Get the size of the figure in inches

This method calculates the physical size of the figure in inches based on the current pixel size and screen DPI.

返回: Size of the figure in inches

◆ hasAxes() [1/2]

bool QwtFigure::hasAxes ( ) const

Check if the figure has any axes

This method returns true if the figure contains at least one QwtPlot.

返回: true if the figure has axes, false otherwise

◆ hasAxes() [2/2]

bool QwtFigure::hasAxes ( QwtPlot * plot ) const

Check if the figure contains a specific plot

This method returns true if the figure contains the specified QwtPlot.

参数

plot	QwtPlot to check

返回: true if the figure contains the plot, false otherwise

◆ plotUnderPos()

QwtPlot * QwtFigure::plotUnderPos ( const QPoint & pos ) const

Get the plot under a position

This method returns the QwtPlot under the specified position. If no plot is found, nullptr is returned. Hidden windows are not considered.

参数

pos	Position to query

返回: Pointer to the QwtPlot under the position, or nullptr if not found

◆ removeAxes()

void QwtFigure::removeAxes ( QwtPlot * plot )

Remove a specific axes (plot) from the figure

This method removes the specified QwtPlot from the figure.

参数

plot	QwtPlot to remove

注解: This function does not destroy the QwtPlot object. You need to call deleteLater() manually.

◆ removeAxisAlignment()

bool QwtFigure::removeAxisAlignment	(	const QList< QwtPlot * > &	plots,
		int	axisId
	)

Remove specified axis alignment configuration

This method removes the alignment configuration for the specified plots and axis.

参数

plots	List of plots to remove from alignment
axisId	Axis ID to remove from alignment

返回: true if successfully removed, false otherwise

◆ replotAll()

void QwtFigure::replotAll ( )

Update all plots in the figure

This method calls replot on all plots in the figure.

◆ saveFig() [1/3]

bool QwtFigure::saveFig	(	const QString &	filename,
		int	dpi = `-1`
	)		const

Save the figure to a file with specified DPI

This method saves the figure to an image file with the specified DPI.

参数

filename	Name of the file to save
dpi	Dots per inch for the saved image (-1 to use screen DPI)

返回: true if saved successfully, false otherwise

◆ saveFig() [2/3]

QPixmap QwtFigure::saveFig ( int dpi = -1 ) const

Save the figure to a QPixmap with specified DPI

This method renders the figure to a QPixmap with the specified DPI. If DPI is -1, the current screen DPI is used.

参数

dpi	Dots per inch for the saved image (-1 to use screen DPI)

返回: QPixmap containing the rendered figure

◆ saveFig() [3/3]

QPixmap QwtFigure::saveFig ( QSizeF & inchesSize ) const

Save the figure to a QPixmap with specified size in inches

This method renders the figure to a QPixmap with the specified physical size in inches. The current DPI setting of the figure is used to calculate the pixel size.

参数

inchesSize Physical size in inches

返回: QPixmap containing the rendered figure

◆ sca()

void QwtFigure::sca ( QwtPlot * plot )

Set the current axes (plot)

This is a convenience method that calls setCurrentAxes.

参数

plot	QwtPlot to set as current

◆ setCurrentAxes()

void QwtFigure::setCurrentAxes ( QwtPlot * plot )

Set the current axes (plot)

This method sets the specified QwtPlot as the current active axes in the figure.

参数

plot	QwtPlot to set as current

◆ setEdgeColor()

void QwtFigure::setEdgeColor ( const QColor & color )

Set the edge color of the figure

This method sets the border color of the figure.

参数

color Border color

◆ setEdgeLineWidth()

void QwtFigure::setEdgeLineWidth ( int width )

Set the edge line width of the figure

This method sets the border line width of the figure.

参数

width Border line width in pixels

◆ setFaceBrush()

void QwtFigure::setFaceBrush ( const QBrush & brush )

Set the face brush of the figure

This method sets the background brush of the figure, allowing for more complex backgrounds (gradients, textures, etc.).

参数

brush Background brush

◆ setFaceColor()

void QwtFigure::setFaceColor ( const QColor & color )

Set the face color of the figure

This method sets the background color of the figure.

参数

color Background color

◆ setSizeInches() [1/2]

void QwtFigure::setSizeInches ( const QSizeF & size )

Set the size of the figure in inches

This method sets the size of the figure in inches, converting to pixels based on the screen DPI.

参数

size	Size in inches

◆ setSizeInches() [2/2]

void QwtFigure::setSizeInches	(	float	width,
		float	height
	)

Set the size of the figure in inches

This method sets the size of the figure in inches, converting to pixels based on the screen DPI.

参数

width	Width in inches
height	Height in inches

◆ setWidgetNormPos()

void QwtFigure::setWidgetNormPos	(	QWidget *	widget,
		const QRectF &	rect
	)

Change the normalized position of an already added widget. If the widget hasn't been added yet, this function has no effect.

参数

widget
rect

◆ takeAxes()

bool QwtFigure::takeAxes ( QwtPlot * plot )

Take a specific axes (plot) from the figure without deleting it

参数

plot	Pointer to the QwtPlot to take

返回: true if successfully taken, false otherwise

注解: If the removed plot is the current active axes, currentAxesChanged signal is emitted first, then axesRemoved signal.; If the figure has no plots after removal, currentAxesChanged signal is emitted with nullptr.; If a plot has parasite axes, they will be hidden and have parent widget set to nullptr.

◆ widgetNormRect()

QRectF QwtFigure::widgetNormRect ( QWidget * w ) const

Get the normalized rectangle for a widget

This method returns the normalized coordinates [0,1] for the specified axes in the figure. If the widget is not found in the figure, an invalid QRectF is returned.

参数

widget Widget to query

返回: Normalized coordinates [left, top, width, height] in range [0,1], or invalid QRectF if not found

该类的文档由以下文件生成:

/home/runner/work/QWT/QWT/src/plot/qwt_figure.h
/home/runner/work/QWT/QWT/src/plot/qwt_figure.cpp

类

信号

Public 成员函数

静态 Public 成员函数

Protected 成员函数

详细描述

构造及析构函数说明

◆ QwtFigure()

成员函数说明

◆ addAxes() [1/2]

◆ addAxes() [2/2]

◆ addAxisAlignment()

◆ addGridAxes()

◆ addWidget() [1/2]

◆ addWidget() [2/2]

◆ alignAxes()

◆ allAxes()

◆ applyAlignmentsForAxis()

◆ applyAllAxisAlignments()

◆ axesAdded

◆ axesNormRect()

◆ axesRemoved

◆ axisAligmentCount()

◆ axisAligmentInfo()

◆ calcActualRect()

◆ calcNormRect()

◆ clear()

◆ clearAxisAlignment()

◆ createParasiteAxes()

◆ currentAxes()

◆ currentAxesChanged

◆ edgeColor()

◆ edgeLineWidth()

◆ faceBrush()

◆ faceColor()

◆ gca()

◆ getParasiteAxes()

◆ getSizeInches()

◆ hasAxes() [1/2]

◆ hasAxes() [2/2]

◆ plotUnderPos()

◆ removeAxes()

◆ removeAxisAlignment()

◆ replotAll()

◆ saveFig() [1/3]

◆ saveFig() [2/3]

◆ saveFig() [3/3]

◆ sca()

◆ setCurrentAxes()

◆ setEdgeColor()

◆ setEdgeLineWidth()

◆ setFaceBrush()

◆ setFaceColor()

◆ setSizeInches() [1/2]

◆ setSizeInches() [2/2]

◆ setWidgetNormPos()

◆ takeAxes()

◆ widgetNormRect()