QwtScaleDraw Class Reference

Inheritance diagram for QwtScaleDraw:

[legend]Collaboration diagram for QwtScaleDraw:

[legend]List of all members.

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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.

Definition at line 30 of file qwt_scale_draw.h.

Public Types
enum	Alignment {   BottomScale,   TopScale,   LeftScale,   RightScale }
Public Member Functions
	QwtScaleDraw ()
	QwtScaleDraw (const QwtScaleDraw &)
virtual	~QwtScaleDraw ()
QwtScaleDraw &	operator= (const QwtScaleDraw &other)
void	getBorderDistHint (const QFont &, int &start, int &end) const
int	minLabelDist (const QFont &) const
int	minLength (const QPen &, const QFont &) const
virtual int	extent (const QPen &, const QFont &) const
void	move (int x, int y)
void	move (const QPoint &)
void	setLength (int length)
Alignment	alignment () const
void	setAlignment (Alignment)
Qt::Orientation	orientation () const
QPoint	pos () const
int	length () const
void	setLabelAlignment (Qt::Alignment)
Qt::Alignment	labelAlignment () const
void	setLabelRotation (double rotation)
double	labelRotation () const
int	maxLabelHeight (const QFont &) const
int	maxLabelWidth (const QFont &) const
QPoint	labelPosition (double val) const
QRect	labelRect (const QFont &, double val) const
QSize	labelSize (const QFont &, double val) const
Protected Member Functions
QMatrix	labelMatrix (const QPoint &, const QSize &) const
virtual void	drawTick (QPainter *p, double val, int len) const
virtual void	drawBackbone (QPainter *p) const
virtual void	drawLabel (QPainter *p, double val) const

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Member Enumeration Documentation

enum QwtScaleDraw::Alignment

Alignment of the scale draw See also: setAlignment(), alignment() Definition at line 37 of file qwt_scale_draw.h.

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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. Definition at line 60 of file qwt_scale_draw.cpp. References setLength().

QwtScaleDraw::QwtScaleDraw (  const QwtScaleDraw &   )

Copy constructor. Definition at line 67 of file qwt_scale_draw.cpp. References d_data.

QwtScaleDraw::~QwtScaleDraw (   )  [virtual]

Destructor. Definition at line 74 of file qwt_scale_draw.cpp.

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Member Function Documentation

QwtScaleDraw::Alignment QwtScaleDraw::alignment (   )  const

Return alignment of the scale See also: setAlignment() Definition at line 91 of file qwt_scale_draw.cpp. Referenced by QwtScaleWidget::alignment(), drawBackbone(), labelMatrix(), and labelPosition().

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

Draws the baseline of the scale Parameters: painter  Painter See also: drawTick(), drawLabel() Implements QwtAbstractScaleDraw. Definition at line 507 of file qwt_scale_draw.cpp. References alignment(), QwtPainter::drawLine(), and pos().

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 Implements QwtAbstractScaleDraw. Definition at line 612 of file qwt_scale_draw.cpp. References QwtText::draw(), QwtText::isEmpty(), labelMatrix(), labelPosition(), labelSize(), pos(), QwtText::textSize(), and QwtAbstractScaleDraw::tickLabel().

void QwtScaleDraw::drawTick (  QPainter *  painter, double  value, int  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. Definition at line 406 of file qwt_scale_draw.cpp. References QwtMetricsMap::isIdentity(), QwtMetricsMap::layoutToDevice(), QwtMetricsMap::layoutToDeviceX(), QwtMetricsMap::layoutToDeviceY(), QwtAbstractScaleDraw::map(), QwtPainter::metricsMap(), orientation(), pos(), QwtPainter::resetMetricsMap(), and QwtAbstractScaleDraw::scaleMap().

int QwtScaleDraw::extent (  const QPen &  pen, 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: pen  Pen that is used for painting backbone and ticks font  Font used for painting the labels See also: minLength() Implements QwtAbstractScaleDraw. Definition at line 280 of file qwt_scale_draw.cpp. References QwtAbstractScaleDraw::hasComponent(), QwtAbstractScaleDraw::majTickLength(), maxLabelHeight(), maxLabelWidth(), QwtAbstractScaleDraw::minimumExtent(), orientation(), and QwtAbstractScaleDraw::spacing(). Referenced by QwtThermo::minimumSizeHint(), and QwtSlider::minimumSizeHint().

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 Definition at line 139 of file qwt_scale_draw.cpp. References QwtAbstractScaleDraw::hasComponent(), labelRect(), QwtAbstractScaleDraw::map(), orientation(), QwtAbstractScaleDraw::scaleDiv(), and QwtScaleDiv::ticks(). Referenced by QwtSlider::layoutSlider(), QwtThermo::layoutThermo(), QwtSlider::minimumSizeHint(), and minLength().

Qt::Alignment QwtScaleDraw::labelAlignment (   )  const

Returns: the label flags See also: setLabelAlignment(), labelRotation() Definition at line 834 of file qwt_scale_draw.cpp. Referenced by labelMatrix().

QMatrix QwtScaleDraw::labelMatrix (  const QPoint &  pos, const QSize &  size )  const [protected]

Calculate the matrix 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() Definition at line 646 of file qwt_scale_draw.cpp. References alignment(), labelAlignment(), and labelRotation(). Referenced by drawLabel().

QPoint 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 Definition at line 356 of file qwt_scale_draw.cpp. References alignment(), QwtAbstractScaleDraw::hasComponent(), QwtAbstractScaleDraw::majTickLength(), QwtAbstractScaleDraw::map(), QwtAbstractScaleDraw::spacing(), and QwtScaleMap::transform(). Referenced by drawLabel(), and labelRect().

QRect 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 Definition at line 717 of file qwt_scale_draw.cpp. References QwtText::isEmpty(), labelPosition(), labelSize(), pos(), QwtText::textSize(), and QwtAbstractScaleDraw::tickLabel(). Referenced by getBorderDistHint(), labelSize(), and minLabelDist().

double QwtScaleDraw::labelRotation (   )  const

Returns: the label rotation See also: setLabelRotation(), labelAlignment() Definition at line 788 of file qwt_scale_draw.cpp. Referenced by labelMatrix().

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

Calculate the size that is needed to draw a label Parameters: font  Label font value  Value Definition at line 761 of file qwt_scale_draw.cpp. References labelRect(). Referenced by drawLabel(), labelRect(), maxLabelHeight(), and maxLabelWidth().

int QwtScaleDraw::length (   )  const

Returns: the length of the backbone See also: setLength(), pos() Definition at line 599 of file qwt_scale_draw.cpp.

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

Parameters: font  Font Returns: the maximum height of a label Definition at line 867 of file qwt_scale_draw.cpp. References labelSize(), QwtAbstractScaleDraw::scaleDiv(), and QwtScaleDiv::ticks(). Referenced by extent().

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

Parameters: font  Font Returns: the maximum width of a label Definition at line 844 of file qwt_scale_draw.cpp. References labelSize(), QwtAbstractScaleDraw::scaleDiv(), and QwtScaleDiv::ticks(). Referenced by extent().

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() Definition at line 192 of file qwt_scale_draw.cpp. References QwtAbstractScaleDraw::hasComponent(), labelRect(), orientation(), QwtAbstractScaleDraw::scaleDiv(), and QwtScaleDiv::ticks(). Referenced by minLength().

int QwtScaleDraw::minLength (  const QPen &  pen, const QFont &  font )  const

Calculate the minimum length that is needed to draw the scale Parameters: pen  Pen that is used for painting backbone and ticks font  Font used for painting the labels See also: extent() Definition at line 318 of file qwt_scale_draw.cpp. References getBorderDistHint(), QwtAbstractScaleDraw::hasComponent(), minLabelDist(), QwtAbstractScaleDraw::scaleDiv(), and QwtScaleDiv::ticks(). Referenced by QwtThermo::minimumSizeHint(), and QwtSlider::minimumSizeHint().

void QwtScaleDraw::move (  const QPoint &  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() Definition at line 566 of file qwt_scale_draw.cpp.

QwtScaleDraw & QwtScaleDraw::operator= (  const QwtScaleDraw &  other  )

Assignment operator. Definition at line 80 of file qwt_scale_draw.cpp. References d_data.

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() Definition at line 115 of file qwt_scale_draw.cpp. Referenced by QwtScaleWidget::drawColorBar(), drawTick(), extent(), getBorderDistHint(), minLabelDist(), and QwtPlot::printScale().

QPoint QwtScaleDraw::pos (   )  const

Returns: Origin of the scale See also: move(), length() Definition at line 576 of file qwt_scale_draw.cpp. Referenced by drawBackbone(), drawLabel(), drawTick(), and labelRect().

void QwtScaleDraw::setAlignment (  Alignment  align  )

Set the alignment of the scale The default alignment is QwtScaleDraw::BottomScale See also: alignment() Definition at line 102 of file qwt_scale_draw.cpp. Referenced by QwtThermo::layoutThermo(), and QwtScaleWidget::setScaleDraw().

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(). Definition at line 821 of file qwt_scale_draw.cpp.

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(). Definition at line 779 of file qwt_scale_draw.cpp.

void QwtScaleDraw::setLength (  int  length  )

Set the length of the backbone. The length doesn't include the space needed for overlapping labels. See also: move(), minLabelDist() Definition at line 589 of file qwt_scale_draw.cpp. Referenced by QwtSlider::layoutSlider(), QwtThermo::layoutThermo(), and QwtScaleDraw().

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