A class for drawing scales 更多...

#include <qwt_scale_draw.h>

类 QwtScaleDraw 继承关系图:

类
struct	CornerTargets
	Corner miter target positions in device coordinates 更多...

class	PrivateData

Public 类型
enum	Alignment { BottomScale , TopScale , LeftScale , RightScale }
	Alignment of the scale draw 更多...

enum	CornerMiterFlag { NoMiter = 0x0 , MiterAtStart = 0x1 , MiterAtEnd = 0x2 }
	Corner miter flags 更多...

Public 类型继承自 QwtAbstractScaleDraw
enum	ScaleComponent { Backbone = 0x01 , Ticks = 0x02 , Labels = 0x04 }
	Components of a scale 更多...

Public 成员函数
	QwtScaleDraw ()
	Constructor

void	setCornerMiter (CornerMiter miter)
	Set the corner miter flags

CornerMiter	cornerMiter () const
	Get the corner miter flags

void	setCornerTargets (const CornerTargets &targets)
	Set the corner miter target positions (device coordinates)

CornerTargets	cornerTargets () const
	Get the corner miter target positions

void	getBorderDistHint (const QFont &, int &start, int &end) const
	Get the border distance hint

int	minLabelDist (const QFont &) const
	Get the minimum label distance

int	minLength (const QFont &) const
	Get the minimum length

virtual double	extent (const QFont &) const override
	Calculate the width/height that is needed for a vertical/horizontal scale

void	move (double x, double y)
	Move the position of the scale

void	move (const QPointF &)
	Move the position of the scale

void	setLength (double length)
	Set the length of the backbone

Alignment	alignment () const
	Return alignment of the scale

void	setAlignment (Alignment)
	Set the alignment

Qt::Orientation	orientation () const
	Return the orientation

QPointF	pos () const
	Get origin of the scale

double	length () const
	Get the length of the backbone

void	setLabelAlignment (Qt::Alignment)
	Set the label alignment

Qt::Alignment	labelAlignment () const
	Get the label flags

void	setLabelRotation (double rotation)
	Set the label rotation

double	labelRotation () const
	Get the label rotation

int	maxLabelHeight (const QFont &) const
	Get the maximum label height

int	maxLabelWidth (const QFont &) const
	Get the maximum label width

QPointF	labelPosition (double value) const
	Get the label position for a value

QRectF	labelRect (const QFont &, double value) const
	Get the label rectangle for a value

QSizeF	labelSize (const QFont &, double value) const
	Get the label size for a value

QRect	boundingLabelRect (const QFont &, double value) const
	Get the bounding label rectangle

void	drawTicksInside (QPainter *, const QRectF &canvasRect, const QwtScaleMap &) const
	Draw the ticks from the edges of a canvas towards its interior

Public 成员函数继承自 QwtAbstractScaleDraw
	QwtAbstractScaleDraw ()
	Constructor for QwtAbstractScaleDraw

void	setScaleDiv (const QwtScaleDiv &)
	Set the scale division

const QwtScaleDiv &	scaleDiv () const
	Return the scale division

void	setTransformation (QwtTransform *)
	Set the scale transformation

const QwtScaleMap &	scaleMap () const
	Return the scale map (const version)

QwtScaleMap &	scaleMap ()
	Return the scale map (non-const version)

void	enableComponent (ScaleComponent, bool enable=true)
	Enable or disable a scale component

bool	hasComponent (ScaleComponent) const
	Check if a component is enabled

void	setTickLength (QwtScaleDiv::TickType, double length)
	Set the length of the ticks

double	tickLength (QwtScaleDiv::TickType) const
	Get the length of the ticks

double	maxTickLength () const
	Get the length of the longest tick

void	setSpacing (double)
	Set the spacing between tick and labels

double	spacing () const
	Get the spacing

void	setPenWidthF (qreal width)
	Specify the width of the scale pen

qreal	penWidthF () const
	Get the scale pen width

void	setSelected (bool on)
	Set whether the scale draw is selected

bool	isSelected () const
	Check if the scale draw is selected

void	setSelectedPenWidthOffset (qreal offset=1)
	Set the pen width offset for the axis when it is in selected state

qreal	selectedPenWidthOffset () const
	Get the current pen width offset for the axis when it is in selected state

virtual void	draw (QPainter *, const QPalette &) const
	Draw the scale

virtual QwtText	label (double) const
	Convert a value into its representing label

void	setMinimumExtent (double)
	Set a minimum for the extent

double	minimumExtent () const
	Get the minimum extent

void	invalidateCache ()
	Invalidate the cache used by tickLabel()

Protected 成员函数
QTransform	labelTransformation (const QPointF &, const QSizeF &) const
	Calculate the transformation that is needed to paint a label

virtual void	drawTick (QPainter *, double value, double len) const override
	Draw a tick

virtual void	drawBackbone (QPainter *) const override
	Draws the baseline of the scale

virtual void	drawLabel (QPainter *, double value) const override
	Draws the label for a major scale tick

Protected 成员函数继承自 QwtAbstractScaleDraw
const QwtText &	tickLabel (const QFont &, double value) const
	Convert a value into its representing label and cache it

qreal	effectivePenWidthF () const
	Pen width including the offset of the selected state

详细描述

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.

成员枚举类型说明

◆ Alignment

enum QwtScaleDraw::Alignment

Alignment of the scale draw

参见: setAlignment(), alignment()

枚举值
BottomScale	The scale is below
TopScale	The scale is above
LeftScale	The scale is left
RightScale	The scale is right

◆ CornerMiterFlag

enum QwtScaleDraw::CornerMiterFlag

Corner miter flags

When a miter flag is set, the backbone is extended beyond the corresponding end of the scale into a corner shared with a perpendicular scale, so that both backbones intersect instead of ending in a diagonal step. The extension reaches the far edge of the perpendicular backbone band closest to the canvas when a target has been set with setCornerTargets(), so that the whole corner square is covered for any pen width; otherwise it falls back to one pixel beyond the end of the scale. For vertical scales AtStart/AtEnd refer to the top/bottom end, for horizontal scales to the left/right end.

参见: setCornerMiter(), cornerMiter(), setCornerTargets()

枚举值
NoMiter	Do not extend the backbone
MiterAtStart	Extend the backbone beyond the start of the scale
MiterAtEnd	Extend the backbone beyond the end of the scale

构造及析构函数说明

◆ QwtScaleDraw()

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.

成员函数说明

◆ alignment()

QwtScaleDraw::Alignment QwtScaleDraw::alignment ( ) const

Return alignment of the scale

返回: the alignment; Alignment of the scale

参见: setAlignment()

◆ boundingLabelRect()

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

Get the bounding label rectangle

Find the bounding rectangle for the label

The coordinates of the rectangle are absolute ( calculated from pos() ) in direction of the tick.

参数

font	Font used for painting
value	Value

返回: Bounding rectangle

参见: labelRect()

◆ cornerMiter()

QwtScaleDraw::CornerMiter QwtScaleDraw::cornerMiter ( ) const

Get the corner miter flags

返回: the corner miter flags; Flags specifying which ends of the backbone are extended

参见: setCornerMiter()

◆ cornerTargets()

QwtScaleDraw::CornerTargets QwtScaleDraw::cornerTargets ( ) const

Get the corner miter target positions

返回: the corner miter target positions; Target positions in device coordinates, qQNaN() when unset

参见: setCornerTargets()

◆ drawBackbone()

void QwtScaleDraw::drawBackbone ( QPainter * painter ) const

overrideprotectedvirtual

Draws the baseline of the scale

参数

painter Painter

参见: drawTick(), drawLabel()

实现了 QwtAbstractScaleDraw.

◆ drawLabel()

void QwtScaleDraw::drawLabel	(	QPainter *	painter,
		double	value
	)		const

overrideprotectedvirtual

Draws the label for a major scale tick

参数

painter	Painter
value	Value

参见: drawTick(), drawBackbone(), boundingLabelRect()

实现了 QwtAbstractScaleDraw.

◆ drawTick()

void QwtScaleDraw::drawTick	(	QPainter *	painter,
		double	value,
		double	len
	)		const

overrideprotectedvirtual

Draw a tick

参数

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

参见: drawBackbone(), drawLabel()

实现了 QwtAbstractScaleDraw.

◆ drawTicksInside()

void QwtScaleDraw::drawTicksInside	(	QPainter *	painter,
		const QRectF &	canvasRect,
		const QwtScaleMap &	map
	)		const

Draw the ticks from the edges of a canvas towards its interior

参数

painter	Painter
canvasRect	Canvas rectangle in painter coordinates
map	Scale map of the axis on the canvas

Used by QwtPlot for axes with QwtPlot::TickInside. The ticks start at the canvas edge adjacent to the backbone band and grow into the canvas, following the same device pixel rules as the backbone and the outside ticks of draw(): the thickness is qMax( 1, round( pen width ) ) device pixels without being scaled by the device pixel ratio, and every tick is aligned to the device pixel grid. Stroking a pen of a fractional logical width instead would make the ticks thicker than the backbone at device pixel ratios above one and rasterize ticks at different subpixel positions with different widths.

参见: drawTick()

◆ extent()

double QwtScaleDraw::extent ( const QFont & font ) const

overridevirtual

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.

参数

font	Font used for painting the labels

返回: Extent

参见: minLength()

实现了 QwtAbstractScaleDraw.

◆ getBorderDistHint()

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

Get the border distance hint

Determine the minimum border distance

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

参数

font	Font
start	Start border distance
end	End border distance

◆ labelAlignment()

Qt::Alignment QwtScaleDraw::labelAlignment ( ) const

Get the label flags

返回: the label alignment; the label flags

参见: setLabelAlignment(), labelRotation()

◆ labelPosition()

QPointF QwtScaleDraw::labelPosition ( double value ) const

Get the label position for a value

Find the position, where to paint a label

The position has a distance that depends on the length of the ticks in direction of the alignment().

参数

value Value

返回: Position, where to paint a label

◆ labelRect()

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

Get the label rectangle for a value

Find the bounding rectangle for the label

The coordinates of the rectangle are relative to spacing + tick length from the backbone in direction of the tick.

参数

font	Font used for painting
value	Value

返回: Bounding rectangle that is needed to draw a label

◆ labelRotation()

double QwtScaleDraw::labelRotation ( ) const

Get the label rotation

返回: the label rotation; the label rotation

参见: setLabelRotation(), labelAlignment()

◆ labelSize()

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

Get the label size for a value

Calculate the size that is needed to draw a label

参数

font	Label font
value	Value

返回: Size that is needed to draw a label

◆ labelTransformation()

QTransform QwtScaleDraw::labelTransformation	(	const QPointF &	pos,
		const QSizeF &	size
	)		const

protected

Calculate the transformation that is needed to paint a label

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

参数

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

返回: Transformation matrix

参见: setLabelAlignment(), setLabelRotation()

◆ length()

double QwtScaleDraw::length ( ) const

Get the length of the backbone

返回: the length; the length of the backbone

参见: setLength(), pos()

◆ maxLabelHeight()

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

Get the maximum label height

Get the maximum height of a label

参数

font Font

返回: the maximum height of a label

◆ maxLabelWidth()

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

Get the maximum label width

Get the maximum width of a label

参数

font Font

返回: the maximum width of a label

◆ minLabelDist()

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

Get the minimum label distance

Determine the minimum distance between two labels

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

参数

font Font

返回: The maximum width of a label

参见: getBorderDistHint()

◆ minLength()

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

Get the minimum length

Calculate the minimum length that is needed to draw the scale

参数

font	Font used for painting the labels

返回: Minimum length that is needed to draw the scale

参见: extent()

◆ move() [1/2]

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.

参数

pos	Origin of the scale

参见: pos(), setLength()

◆ move() [2/2]

void QwtScaleDraw::move	(	double	x,
		double	y
	)

inline

Move the position of the scale

参数

x	X coordinate
y	Y coordinate

参见: move(const QPointF&)

◆ orientation()

Qt::Orientation QwtScaleDraw::orientation ( ) const

Return the orientation

返回: the orientation

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

返回: Orientation of the scale

参见: alignment()

◆ pos()

QPointF QwtScaleDraw::pos ( ) const

Get origin of the scale

返回: the position; Origin of the scale

参见: move(), length()

◆ setAlignment()

void QwtScaleDraw::setAlignment ( Alignment align )

Set the alignment

Set the alignment of the scale

参数

align Alignment of the scale

The default alignment is QwtScaleDraw::BottomScale

参见: alignment()

◆ setCornerMiter()

void QwtScaleDraw::setCornerMiter ( CornerMiter miter )

Set the corner miter flags

参数

miter Flags specifying which ends of the backbone are extended into a corner shared with a perpendicular scale

QwtScaleWidget sets the flags from the visibility of the perpendicular axes of the plot; standalone use keeps NoMiter.

参见: cornerMiter()

◆ setCornerTargets()

void QwtScaleDraw::setCornerTargets ( const CornerTargets & targets )

Set the corner miter target positions (device coordinates)

Set the corner miter target positions

参数

targets Target positions in device coordinates

When a miter flag is set and its target is valid, the backbone is extended exactly to that position instead of one pixel beyond the end of the scale; border ticks snap to the same target. The target is the near edge of the perpendicular backbone band closest to the canvas. QwtScaleWidget and QwtPlotRenderer compute the targets from the geometry of the perpendicular axes; standalone use keeps them unset and the historical fallback.

参见: setCornerMiter(), cornerTargets(), CornerTargets

◆ setLabelAlignment()

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

Set the label alignment

Change the label flags

Labels are aligned to the point tick length + 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.

参数

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

参见: setLabelRotation(), labelRotation(), labelAlignment()

警告: 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().

◆ setLabelRotation()

void QwtScaleDraw::setLabelRotation ( double rotation )

Set the label 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.

参数

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

参见: setLabelAlignment(), labelRotation(), labelAlignment()

◆ setLength()

void QwtScaleDraw::setLength ( double length )

Set the length of the backbone

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

参数

length Length of the backbone

参见: move(), minLabelDist()

该类的文档由以下文件生成:

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

类

Public 类型

Public 成员函数

Protected 成员函数

详细描述

成员枚举类型说明

◆ Alignment

◆ CornerMiterFlag

构造及析构函数说明

◆ QwtScaleDraw()

成员函数说明

◆ alignment()

◆ boundingLabelRect()

◆ cornerMiter()

◆ cornerTargets()

◆ drawBackbone()

◆ drawLabel()

◆ drawTick()

◆ drawTicksInside()

◆ extent()

◆ getBorderDistHint()

◆ labelAlignment()

◆ labelPosition()

◆ labelRect()

◆ labelRotation()

◆ labelSize()

◆ labelTransformation()

◆ length()

◆ maxLabelHeight()

◆ maxLabelWidth()

◆ minLabelDist()

◆ minLength()

◆ move() [1/2]

◆ move() [2/2]

◆ orientation()

◆ pos()

◆ setAlignment()

◆ setCornerMiter()

◆ setCornerTargets()

◆ setLabelAlignment()

◆ setLabelRotation()

◆ setLength()