#include <qwt_scale_draw.h>

Inherits QwtAbstractScaleDraw.

Public Types
enum	Alignment { BottomScale, TopScale, LeftScale, RightScale }
enum	ScaleComponent { Backbone = 0x01, Ticks = 0x02, Labels = 0x04 }
typedef QFlags< ScaleComponent >	ScaleComponents
Public Member Functions
Alignment	alignment () const
QRect	boundingLabelRect (const QFont &, double val) const
virtual void	draw (QPainter *, const QPalette &) const
void	enableComponent (ScaleComponent, bool enable=true)
virtual double	extent (const QFont &) const
void	getBorderDistHint (const QFont &, int &start, int &end) const
bool	hasComponent (ScaleComponent) const
virtual QwtText	label (double) const
Qt::Alignment	labelAlignment () const
QPointF	labelPosition (double val) const
QRectF	labelRect (const QFont &, double val) const
double	labelRotation () const
QSizeF	labelSize (const QFont &, double val) const
double	length () const
int	maxLabelHeight (const QFont &) const
int	maxLabelWidth (const QFont &) const
double	maxTickLength () const
double	minimumExtent () const
int	minLabelDist (const QFont &) const
int	minLength (const QFont &) const
void	move (double x, double y)
void	move (const QPointF &)
Qt::Orientation	orientation () const
int	penWidth () const
QPointF	pos () const
	QwtScaleDraw ()
const QwtScaleDiv &	scaleDiv () const
const QwtScaleMap &	scaleMap () const
QwtScaleMap &	scaleMap ()
void	setAlignment (Alignment)
void	setLabelAlignment (Qt::Alignment)
void	setLabelRotation (double rotation)
void	setLength (double length)
void	setMinimumExtent (double)
void	setPenWidth (int width)
void	setScaleDiv (const QwtScaleDiv &s)
void	setSpacing (double margin)
void	setTickLength (QwtScaleDiv::TickType, double length)
void	setTransformation (QwtScaleTransformation *)
double	spacing () const
double	tickLength (QwtScaleDiv::TickType) const
virtual	~QwtScaleDraw ()
Protected Member Functions
virtual void	drawBackbone (QPainter *) const
virtual void	drawLabel (QPainter *, double val) const
virtual void	drawTick (QPainter *, double val, double len) const
void	invalidateCache ()
QTransform	labelTransformation (const QPointF &, const QSizeF &) const
const QwtText &	tickLabel (const QFont &, double value) const

Detailed Description

A class for drawing scales.

QwtScaleDraw can be used to draw linear or logarithmic scales. A scale has a position, an alignment and a length, which can be specified . The labels can be rotated and aligned to the ticks using setLabelRotation() and setLabelAlignment().

After a scale division has been specified as a QwtScaleDiv object using QwtAbstractScaleDraw::setScaleDiv(const QwtScaleDiv &s), the scale can be drawn with the QwtAbstractScaleDraw::draw() member.

Member Typedef Documentation

typedef QFlags<ScaleComponent> QwtAbstractScaleDraw::ScaleComponents [inherited]

Scale components.

Member Enumeration Documentation

enum QwtScaleDraw::Alignment

Alignment of the scale draw

See also:: setAlignment(), alignment()

Enumerator:

BottomScale	The scale is below.
TopScale	The scale is above.
LeftScale	The scale is left.
RightScale	The scale is right.

enum QwtAbstractScaleDraw::ScaleComponent [inherited]

Components of a scale

See also:: enableComponent(), hasComponent

Enumerator:

Backbone	Backbone = the line where the ticks are located.
Ticks	Ticks.
Labels	Labels.

Constructor & Destructor Documentation

QwtScaleDraw::QwtScaleDraw ( )

Constructor.

The range of the scale is initialized to [0, 100], The position is at (0, 0) with a length of 100. The orientation is QwtAbstractScaleDraw::Bottom.

QwtScaleDraw::~QwtScaleDraw ( ) [virtual]

Destructor.

Member Function Documentation

QwtScaleDraw::Alignment QwtScaleDraw::alignment ( ) const

Return alignment of the scale

See also:: setAlignment()

QRect QwtScaleDraw::boundingLabelRect	(	const QFont &	font,
		double	value
	)		const

Find the bounding rect for the label. The coordinates of the rect are absolute coordinates ( calculated from pos() ). in direction of the tick.

Parameters:

font	Font used for painting
value	Value

See also:: labelRect()

void QwtAbstractScaleDraw::draw	(	QPainter *	painter,
		const QPalette &	palette
	)		const `[virtual, inherited]`

Draw the scale.

Parameters:

painter	The painter
palette	Palette, text color is used for the labels, foreground color for ticks and backbone

void QwtScaleDraw::drawBackbone ( QPainter * painter ) const [protected, virtual]

Draws the baseline of the scale

Parameters:

painter Painter

See also:: drawTick(), drawLabel()

Implements QwtAbstractScaleDraw.

void QwtScaleDraw::drawLabel	(	QPainter *	painter,
		double	value
	)		const `[protected, virtual]`

Draws the label for a major scale tick

Parameters:

painter	Painter
value	Value

See also:: drawTick(), drawBackbone(), boundingLabelRect()

Implements QwtAbstractScaleDraw.

void QwtScaleDraw::drawTick	(	QPainter *	painter,
		double	value,
		double	len
	)		const `[protected, virtual]`

Draw a tick

Parameters:

painter	Painter
value	Value of the tick
len	Lenght of the tick

See also:: drawBackbone(), drawLabel()

Implements QwtAbstractScaleDraw.

void QwtAbstractScaleDraw::enableComponent	(	ScaleComponent	component,
		bool	enable = `true`
	)		`[inherited]`

En/Disable a component of the scale

Parameters:

component	Scale component
enable	On/Off

See also:: hasComponent()

double QwtScaleDraw::extent ( const QFont & font ) const [virtual]

Calculate the width/height that is needed for a vertical/horizontal scale.

The extent is calculated from the pen width of the backbone, the major tick length, the spacing and the maximum width/height of the labels.

Parameters:

font	Font used for painting the labels

See also:: minLength()

Implements QwtAbstractScaleDraw.

void QwtScaleDraw::getBorderDistHint	(	const QFont &	font,
		int &	start,
		int &	end
	)		const

Determine the minimum border distance.

This member function returns the minimum space needed to draw the mark labels at the scale's endpoints.

Parameters:

font	Font
start	Start border distance
end	End border distance

bool QwtAbstractScaleDraw::hasComponent ( ScaleComponent component ) const [inherited]

Check if a component is enabled

See also:: enableComponent()

void QwtAbstractScaleDraw::invalidateCache ( ) [protected, inherited]

Invalidate the cache used by QwtAbstractScaleDraw::tickLabel

The cache is invalidated, when a new QwtScaleDiv is set. If the labels need to be changed. while the same QwtScaleDiv is set, invalidateCache() needs to be called manually.

QwtText QwtAbstractScaleDraw::label ( double value ) const [virtual, inherited]

Convert a value into its representing label.

The value is converted to a plain text using QLocale::system().toString(value). This method is often overloaded by applications to have individual labels.

Parameters:

value Value

Returns:: Label string.

Reimplemented in QwtDialScaleDraw.

Qt::Alignment QwtScaleDraw::labelAlignment ( ) const

Returns:: the label flags

See also:: setLabelAlignment(), labelRotation()

QPointF QwtScaleDraw::labelPosition ( double value ) const

Find the position, where to paint a label

The position has a distance of majTickLength() + spacing() + 1 from the backbone. The direction depends on the alignment()

Parameters:

value Value

QRectF QwtScaleDraw::labelRect	(	const QFont &	font,
		double	value
	)		const

Find the bounding rect for the label. The coordinates of the rect are relative to spacing + ticklength from the backbone in direction of the tick.

Parameters:

font	Font used for painting
value	Value

double QwtScaleDraw::labelRotation ( ) const

Returns:: the label rotation

See also:: setLabelRotation(), labelAlignment()

QSizeF QwtScaleDraw::labelSize	(	const QFont &	font,
		double	value
	)		const

Calculate the size that is needed to draw a label

Parameters:

font	Label font
value	Value

QTransform QwtScaleDraw::labelTransformation	(	const QPointF &	pos,
		const QSizeF &	size
	)		const `[protected]`

Calculate the transformation that is needed to paint a label depending on its alignment and rotation.

Parameters:

pos	Position where to paint the label
size	Size of the label

See also:: setLabelAlignment(), setLabelRotation()

double QwtScaleDraw::length ( ) const

Returns:: the length of the backbone

See also:: setLength(), pos()

int QwtScaleDraw::maxLabelHeight ( const QFont & font ) const

Parameters:

font Font

Returns:: the maximum height of a label

int QwtScaleDraw::maxLabelWidth ( const QFont & font ) const

Parameters:

font Font

Returns:: the maximum width of a label

double QwtAbstractScaleDraw::maxTickLength ( ) const [inherited]

Returns:: Length of the longest tick

Useful for layout calculations

See also:: tickLength(), setTickLength()

double QwtAbstractScaleDraw::minimumExtent ( ) const [inherited]

Get the minimum extent

See also:: extent(), setMinimumExtent()

int QwtScaleDraw::minLabelDist ( const QFont & font ) const

Determine the minimum distance between two labels, that is necessary that the texts don't overlap.

Parameters:

font Font

Returns:: The maximum width of a label

See also:: getBorderDistHint()

int QwtScaleDraw::minLength ( const QFont & font ) const

Calculate the minimum length that is needed to draw the scale

Parameters:

font	Font used for painting the labels

See also:: extent()

void QwtScaleDraw::move	(	double	x,
		double	y
	)		`[inline]`

Move the position of the scale

See also:: move(const QPointF &)

void QwtScaleDraw::move ( const QPointF & pos )

Move the position of the scale.

The meaning of the parameter pos depends on the alignment:

QwtScaleDraw::LeftScale: The origin is the topmost point of the backbone. The backbone is a vertical line. Scale marks and labels are drawn at the left of the backbone.
QwtScaleDraw::RightScale: The origin is the topmost point of the backbone. The backbone is a vertical line. Scale marks and labels are drawn at the right of the backbone.
QwtScaleDraw::TopScale: The origin is the leftmost point of the backbone. The backbone is a horizontal line. Scale marks and labels are drawn above the backbone.
QwtScaleDraw::BottomScale: The origin is the leftmost point of the backbone. The backbone is a horizontal line Scale marks and labels are drawn below the backbone.

Parameters:

pos	Origin of the scale

See also:: pos(), setLength()

Qt::Orientation QwtScaleDraw::orientation ( ) const

Return the orientation

TopScale, BottomScale are horizontal (Qt::Horizontal) scales, LeftScale, RightScale are vertical (Qt::Vertical) scales.

See also:: alignment()

int QwtAbstractScaleDraw::penWidth ( ) const [inherited]

Returns:: Scale pen width

See also:: setPenWidth()

Reimplemented in QwtDialScaleDraw.

QPointF QwtScaleDraw::pos ( ) const

Returns:: Origin of the scale

See also:: move(), length()

const QwtScaleDiv & QwtAbstractScaleDraw::scaleDiv ( ) const [inherited]

Returns:: scale division

const QwtScaleMap & QwtAbstractScaleDraw::scaleMap ( ) const [inherited]

Returns:: Map how to translate between scale and pixel values

QwtScaleMap & QwtAbstractScaleDraw::scaleMap ( ) [inherited]

Returns:: Map how to translate between scale and pixel values

void QwtScaleDraw::setAlignment ( Alignment align )

Set the alignment of the scale

The default alignment is QwtScaleDraw::BottomScale

See also:: alignment()

void QwtScaleDraw::setLabelAlignment ( Qt::Alignment alignment )

Change the label flags.

Labels are aligned to the point ticklength + spacing away from the backbone.

The alignment is relative to the orientation of the label text. In case of an flags of 0 the label will be aligned depending on the orientation of the scale:

QwtScaleDraw::TopScale: Qt::AlignHCenter | Qt::AlignTop
QwtScaleDraw::BottomScale: Qt::AlignHCenter | Qt::AlignBottom
QwtScaleDraw::LeftScale: Qt::AlignLeft | Qt::AlignVCenter
QwtScaleDraw::RightScale: Qt::AlignRight | Qt::AlignVCenter

Changing the alignment is often necessary for rotated labels.

Parameters:

alignment Or'd Qt::AlignmentFlags see <qnamespace.h>

See also:: setLabelRotation(), labelRotation(), labelAlignment()

Warning:: The various alignments might be confusing. The alignment of the label is not the alignment of the scale and is not the alignment of the flags (QwtText::flags()) returned from QwtAbstractScaleDraw::label().

void QwtScaleDraw::setLabelRotation ( double rotation )

Rotate all labels.

When changing the rotation, it might be necessary to adjust the label flags too. Finding a useful combination is often the result of try and error.

Parameters:

rotation Angle in degrees. When changing the label rotation, the label flags often needs to be adjusted too.

See also:: setLabelAlignment(), labelRotation(), labelAlignment().

void QwtScaleDraw::setLength ( double length )

Set the length of the backbone.

The length doesn't include the space needed for overlapping labels.

See also:: move(), minLabelDist()

void QwtAbstractScaleDraw::setMinimumExtent ( double minExtent ) [inherited]

Set a minimum for the extent.

The extent is calculated from the coomponents of the scale draw. In situations, where the labels are changing and the layout depends on the extent (f.e scrolling a scale), setting an upper limit as minimum extent will avoid jumps of the layout.

Parameters:

minExtent Minimum extent

See also:: extent(), minimumExtent()

void QwtAbstractScaleDraw::setPenWidth ( int width ) [inherited]

Specify the width of the scale pen.

Parameters:

width Pen width

See also:: penWidth()

void QwtAbstractScaleDraw::setScaleDiv ( const QwtScaleDiv & sd ) [inherited]

Change the scale division

Parameters:

sd	New scale division

void QwtAbstractScaleDraw::setSpacing ( double spacing ) [inherited]

Set the spacing between tick and labels.

The spacing is the distance between ticks and labels. The default spacing is 4 pixels.

Parameters:

spacing Spacing

See also:: spacing()

void QwtAbstractScaleDraw::setTickLength	(	QwtScaleDiv::TickType	tickType,
		double	length
	)		`[inherited]`

Set the length of the ticks

Parameters:

tickType	Tick type
length	New length

Warning:: the length is limited to [0..1000]

void QwtAbstractScaleDraw::setTransformation ( QwtScaleTransformation * transformation ) [inherited]

Change the transformation of the scale

Parameters:

transformation New scale transformation

double QwtAbstractScaleDraw::spacing ( ) const [inherited]

Get the spacing.

The spacing is the distance between ticks and labels. The default spacing is 4 pixels.

See also:: setSpacing()

const QwtText & QwtAbstractScaleDraw::tickLabel	(	const QFont &	font,
		double	value
	)		const `[protected, inherited]`

Convert a value into its representing label and cache it.

The conversion between value and label is called very often in the layout and painting code. Unfortunately the calculation of the label sizes might be slow (really slow for rich text in Qt4), so it's necessary to cache the labels.

Parameters:

font	Font
value	Value

Returns:: Tick label

double QwtAbstractScaleDraw::tickLength ( QwtScaleDiv::TickType tickType ) const [inherited]

Return the length of the ticks

See also:: setTickLength(), maxTickLength()

Public Types

Public Member Functions

Protected Member Functions

Detailed Description

Member Typedef Documentation

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation