A collection of QPainter workarounds. More...

#include <qwt_painter.h>

Static Public Member Functions
static void	setPolylineSplitting (bool)
	En/Disable line splitting for the raster paint engine. More...

static bool	polylineSplitting ()

static void	setRoundingAlignment (bool)

static bool	roundingAlignment ()

static bool	roundingAlignment (QPainter *)

static void	drawText (QPainter *, double x, double y, const QString &)
	Wrapper for QPainter::drawText()

static void	drawText (QPainter *, const QPointF &, const QString &)
	Wrapper for QPainter::drawText()

static void	drawText (QPainter *, double x, double y, double w, double h, int flags, const QString &)
	Wrapper for QPainter::drawText()

static void	drawText (QPainter *, const QRectF &, int flags, const QString &)
	Wrapper for QPainter::drawText()

static void	drawSimpleRichText (QPainter *, const QRectF &, int flags, const QTextDocument &)

static void	drawRect (QPainter *, double x, double y, double w, double h)
	Wrapper for QPainter::drawRect()

static void	drawRect (QPainter *, const QRectF &rect)
	Wrapper for QPainter::drawRect()

static void	fillRect (QPainter *, const QRectF &, const QBrush &)
	Wrapper for QPainter::fillRect()

static void	drawEllipse (QPainter *, const QRectF &)
	Wrapper for QPainter::drawEllipse()

static void	drawPie (QPainter *, const QRectF &, int a, int alen)
	Wrapper for QPainter::drawPie()

static void	drawLine (QPainter *, double x1, double y1, double x2, double y2)
	Wrapper for QPainter::drawLine()

static void	drawLine (QPainter *, const QPointF &p1, const QPointF &p2)
	Wrapper for QPainter::drawLine()

static void	drawLine (QPainter *, const QLineF &)
	Wrapper for QPainter::drawLine()

static void	drawPolygon (QPainter *, const QPolygonF &)
	Wrapper for QPainter::drawPolygon()

static void	drawPolyline (QPainter *, const QPolygonF &)
	Wrapper for QPainter::drawPolyline()

static void	drawPolyline (QPainter , const QPointF , int pointCount)
	Wrapper for QPainter::drawPolyline()

static void	drawPolygon (QPainter *, const QPolygon &)
	Wrapper for QPainter::drawPolygon()

static void	drawPolyline (QPainter *, const QPolygon &)
	Wrapper for QPainter::drawPolyline()

static void	drawPolyline (QPainter , const QPoint , int pointCount)
	Wrapper for QPainter::drawPolyline()

static void	drawPoint (QPainter *, const QPoint &)
	Wrapper for QPainter::drawPoint()

static void	drawPoints (QPainter *, const QPolygon &)
	Wrapper for QPainter::drawPoints()

static void	drawPoints (QPainter , const QPoint , int pointCount)
	Wrapper for QPainter::drawPoints()

static void	drawPoint (QPainter *, double x, double y)
	Wrapper for QPainter::drawPoint()

static void	drawPoint (QPainter *, const QPointF &)
	Wrapper for QPainter::drawPoint()

static void	drawPoints (QPainter *, const QPolygonF &)
	Wrapper for QPainter::drawPoints()

static void	drawPoints (QPainter , const QPointF , int pointCount)
	Wrapper for QPainter::drawPoints()

static void	drawPath (QPainter *, const QPainterPath &)
	Wrapper for QPainter::drawPath()

static void	drawImage (QPainter *, const QRectF &, const QImage &)
	Wrapper for QPainter::drawImage()

static void	drawPixmap (QPainter *, const QRectF &, const QPixmap &)
	Wrapper for QPainter::drawPixmap()

static void	drawRoundFrame (QPainter *, const QRectF &, const QPalette &, int lineWidth, int frameStyle)

static void	drawRoundedFrame (QPainter *, const QRectF &, double xRadius, double yRadius, const QPalette &, int lineWidth, int frameStyle)

static void	drawFrame (QPainter *, const QRectF &rect, const QPalette &palette, QPalette::ColorRole foregroundRole, int frameWidth, int midLineWidth, int frameStyle)

static void	drawFocusRect (QPainter , const QWidget )
	Draw a focus rectangle on a widget using its style.

static void	drawFocusRect (QPainter , const QWidget , const QRect &)
	Draw a focus rectangle on a widget using its style.

static void	drawColorBar (QPainter *painter, const QwtColorMap &, const QwtInterval &, const QwtScaleMap &, Qt::Orientation, const QRectF &)

static bool	isAligning (QPainter *painter)

static bool	isX11GraphicsSystem ()

static void	fillPixmap (const QWidget *, QPixmap &, const QPoint &offset=QPoint())

static void	drawBackgound (QPainter painter, const QRectF &rect, const QWidget widget)

static QPixmap	backingStore (QWidget *, const QSize &)

Detailed Description

A collection of QPainter workarounds.

Member Function Documentation

◆ backingStore()

QPixmap QwtPainter::backingStore	(	QWidget *	widget,
		const QSize &	size
	)

static

Returns: A pixmap that can be used as backing store

Parameters

widget	Widget, for which the backingstore is intended
size	Size of the pixmap

◆ drawBackgound()

void QwtPainter::drawBackgound	(	QPainter *	painter,
		const QRectF &	rect,
		const QWidget *	widget
	)

static

Fill rect with the background of a widget

Parameters

painter	Painter
rect	Rectangle to be filled
widget	Widget

See also: QStyle::PE_Widget, QWidget::backgroundRole()

◆ drawColorBar()

void QwtPainter::drawColorBar	(	QPainter *	painter,
		const QwtColorMap &	colorMap,
		const QwtInterval &	interval,
		const QwtScaleMap &	scaleMap,
		Qt::Orientation	orientation,
		const QRectF &	rect
	)

static

Draw a color bar into a rectangle

Parameters

painter	Painter
colorMap	Color map
interval	Value range
scaleMap	Scale map
orientation	Orientation
rect	Traget rectangle

◆ drawFrame()

void QwtPainter::drawFrame	(	QPainter *	painter,
		const QRectF &	rect,
		const QPalette &	palette,
		QPalette::ColorRole	foregroundRole,
		int	frameWidth,
		int	midLineWidth,
		int	frameStyle
	)

static

Draw a rectangular frame

Parameters

painter	Painter
rect	Frame rectangle
palette	Palette
foregroundRole	Foreground role used for QFrame::Plain
frameWidth	Frame width
midLineWidth	Used for QFrame::Box
frameStyle	bitwise OR´ed value of QFrame::Shape and QFrame::Shadow

◆ drawRoundedFrame()

void QwtPainter::drawRoundedFrame	(	QPainter *	painter,
		const QRectF &	rect,
		double	xRadius,
		double	yRadius,
		const QPalette &	palette,
		int	lineWidth,
		int	frameStyle
	)

static

Draw a rectangular frame with rounded borders

Parameters

painter	Painter
rect	Frame rectangle
xRadius	x-radius of the ellipses defining the corners
yRadius	y-radius of the ellipses defining the corners
palette	QPalette::WindowText is used for plain borders QPalette::Dark and QPalette::Light for raised or sunken borders
lineWidth	Line width
frameStyle	bitwise OR´ed value of QFrame::Shape and QFrame::Shadow

◆ drawRoundFrame()

void QwtPainter::drawRoundFrame	(	QPainter *	painter,
		const QRectF &	rect,
		const QPalette &	palette,
		int	lineWidth,
		int	frameStyle
	)

static

Draw a round frame

Parameters

painter	Painter
rect	Frame rectangle
palette	QPalette::WindowText is used for plain borders QPalette::Dark and QPalette::Light for raised or sunken borders
lineWidth	Line width
frameStyle	bitwise OR´ed value of QFrame::Shape and QFrame::Shadow

◆ drawSimpleRichText()

void QwtPainter::drawSimpleRichText	(	QPainter *	painter,
		const QRectF &	rect,
		int	flags,
		const QTextDocument &	text
	)

static

Draw a text document into a rectangle

Parameters

painter	Painter
rect	Traget rectangle
flags	Alignments/Text flags, see QPainter::drawText()
text	Text document

◆ fillPixmap()

void QwtPainter::fillPixmap	(	const QWidget *	widget,
		QPixmap &	pixmap,
		const QPoint &	offset = `QPoint()`
	)

static

Fill a pixmap with the content of a widget

In Qt >= 5.0 QPixmap::fill() is a nop, in Qt 4.x it is buggy for backgrounds with gradients. Thus fillPixmap() offers an alternative implementation.

Parameters

widget	Widget
pixmap	Pixmap to be filled
offset	Offset

See also: QPixmap::fill()

◆ isAligning()

bool QwtPainter::isAligning ( QPainter * painter )

static

Check if the painter is using a paint engine, that aligns coordinates to integers. Today these are all paint engines beside QPaintEngine::Pdf and QPaintEngine::SVG.

If we have an integer based paint engine it is also checked if the painter has a transformation matrix, that rotates or scales.

Parameters

painter Painter

Returns: true, when the painter is aligning

See also: setRoundingAlignment()

◆ isX11GraphicsSystem()

bool QwtPainter::isX11GraphicsSystem ( )

static

Check is the application is running with the X11 graphics system that has some special capabilities that can be used for incremental painting to a widget.

Returns: True, when the graphics system is X11

◆ polylineSplitting()

bool QwtPainter::polylineSplitting ( )

inlinestatic

Returns: True, when line splitting for the raster paint engine is enabled.

See also: setPolylineSplitting()

◆ roundingAlignment() [1/2]

bool QwtPainter::roundingAlignment ( )

inlinestatic

Check whether coordinates should be rounded, before they are painted to a paint engine that rounds to integer values. For other paint engines ( PDF, SVG ), this flag has no effect.

Returns: True, when rounding is enabled

See also: setRoundingAlignment(), isAligning()

◆ roundingAlignment() [2/2]

bool QwtPainter::roundingAlignment ( QPainter * painter )

inlinestatic

Returns: roundingAlignment() && isAligning(painter);

Parameters

painter Painter

◆ setPolylineSplitting()

void QwtPainter::setPolylineSplitting ( bool enable )

static

En/Disable line splitting for the raster paint engine.

In some Qt versions the raster paint engine paints polylines of many points much faster when they are split in smaller chunks: f.e all supported Qt versions >= Qt 5.0 when drawing an antialiased polyline with a pen width >=2.

Also the raster paint engine has a nasty bug in many versions ( Qt 4.8 - ... ) for short lines ( https://codereview.qt-project.org/#/c/99456 ), that is worked around in this mode.

The default setting is true.

See also: polylineSplitting()

◆ setRoundingAlignment()

void QwtPainter::setRoundingAlignment ( bool enable )

static

Enable whether coordinates should be rounded, before they are painted to a paint engine that floors to integer values. For other paint engines ( PDF, SVG ) this flag has no effect. QwtPainter stores this flag only, the rounding itself is done in the painting code ( f.e the plot items ).

The default setting is true.

See also: roundingAlignment(), isAligning()

Static Public Member Functions

Detailed Description

Member Function Documentation

◆ backingStore()

◆ drawBackgound()

◆ drawColorBar()

◆ drawFrame()

◆ drawRoundedFrame()

◆ drawRoundFrame()

◆ drawSimpleRichText()

◆ fillPixmap()

◆ isAligning()

◆ isX11GraphicsSystem()

◆ polylineSplitting()

◆ roundingAlignment() [1/2]

◆ roundingAlignment() [2/2]

◆ setPolylineSplitting()

◆ setRoundingAlignment()