| Qwt User's Guide 6.3.0
    | 
A class for drawing scales. More...
#include <qwt_scale_draw.h>
| Public Types | |
| enum | Alignment { BottomScale , TopScale , LeftScale , RightScale } | 
|  Public Types inherited from QwtAbstractScaleDraw | |
| enum | ScaleComponent { Backbone = 0x01 , Ticks = 0x02 , Labels = 0x04 } | 
| typedef QFlags< ScaleComponent > | ScaleComponents | 
| Public Member Functions | |
| QwtScaleDraw () | |
| Constructor. | |
| virtual | ~QwtScaleDraw () | 
| Destructor. | |
| void | getBorderDistHint (const QFont &, int &start, int &end) const | 
| Determine the minimum border distance. | |
| int | minLabelDist (const QFont &) const | 
| int | minLength (const QFont &) const | 
| virtual double | extent (const QFont &) const override | 
| void | move (double x, double y) | 
| void | move (const QPointF &) | 
| Move the position of the scale. | |
| void | setLength (double length) | 
| Alignment | alignment () const | 
| void | setAlignment (Alignment) | 
| Qt::Orientation | orientation () const | 
| QPointF | pos () const | 
| double | length () const | 
| void | setLabelAlignment (Qt::Alignment) | 
| Change the label flags. | |
| Qt::Alignment | labelAlignment () const | 
| void | setLabelRotation (double rotation) | 
| double | labelRotation () const | 
| int | maxLabelHeight (const QFont &) const | 
| int | maxLabelWidth (const QFont &) const | 
| QPointF | labelPosition (double value) const | 
| QRectF | labelRect (const QFont &, double value) const | 
| QSizeF | labelSize (const QFont &, double value) const | 
| QRect | boundingLabelRect (const QFont &, double value) const | 
| Find the bounding rectangle for the label. | |
|  Public Member Functions inherited from QwtAbstractScaleDraw | |
| QwtAbstractScaleDraw () | |
| Constructor. | |
| virtual | ~QwtAbstractScaleDraw () | 
| Destructor. | |
| void | setScaleDiv (const QwtScaleDiv &) | 
| const QwtScaleDiv & | scaleDiv () const | 
| void | setTransformation (QwtTransform *) | 
| const QwtScaleMap & | scaleMap () const | 
| QwtScaleMap & | scaleMap () | 
| void | enableComponent (ScaleComponent, bool enable=true) | 
| bool | hasComponent (ScaleComponent) const | 
| void | setTickLength (QwtScaleDiv::TickType, double length) | 
| double | tickLength (QwtScaleDiv::TickType) const | 
| double | maxTickLength () const | 
| 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 | 
| 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 | 
| void | invalidateCache () | 
| Protected Member Functions | |
| QTransform | labelTransformation (const QPointF &, const QSizeF &) const | 
| virtual void | drawTick (QPainter *, double value, double len) const override | 
| virtual void | drawBackbone (QPainter *) const override | 
| virtual void | drawLabel (QPainter *, double value) const override | 
|  Protected Member Functions inherited from QwtAbstractScaleDraw | |
| const QwtText & | tickLabel (const QFont &, double value) const | 
| Convert a value into its representing label and cache it. | |
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 35 of file qwt_scale_draw.h.
Alignment of the scale draw
| Enumerator | |
|---|---|
| BottomScale | The scale is below. | 
| TopScale | The scale is above. | 
| LeftScale | The scale is left. | 
| RightScale | The scale is right. | 
Definition at line 42 of file qwt_scale_draw.h.
| 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 292 of file qwt_scale_draw.cpp.
| 
 | virtual | 
Destructor.
Definition at line 299 of file qwt_scale_draw.cpp.
| QwtScaleDraw::Alignment QwtScaleDraw::alignment | ( | ) | const | 
Return alignment of the scale
Definition at line 309 of file qwt_scale_draw.cpp.
| QRect QwtScaleDraw::boundingLabelRect | ( | const QFont & | font, | 
| double | value ) const | 
Find the bounding rectangle for the label.
The coordinates of the rectangle are absolute ( calculated from pos() ). in direction of the tick.
| font | Font used for painting | 
| value | Value | 
Definition at line 794 of file qwt_scale_draw.cpp.
| 
 | overrideprotectedvirtual | 
Draws the baseline of the scale
| painter | Painter | 
Implements QwtAbstractScaleDraw.
Definition at line 668 of file qwt_scale_draw.cpp.
| 
 | overrideprotectedvirtual | 
Draws the label for a major scale tick
| painter | Painter | 
| value | Value | 
Implements QwtAbstractScaleDraw.
Definition at line 762 of file qwt_scale_draw.cpp.
| 
 | overrideprotectedvirtual | 
Draw a tick
| painter | Painter | 
| value | Value of the tick | 
| len | Length of the tick | 
Implements QwtAbstractScaleDraw.
Definition at line 649 of file qwt_scale_draw.cpp.
| 
 | 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.
| font | Font used for painting the labels | 
Implements QwtAbstractScaleDraw.
Definition at line 523 of file qwt_scale_draw.cpp.
| 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.
| font | Font | 
| start | Start border distance | 
| end | End border distance | 
Definition at line 361 of file qwt_scale_draw.cpp.
| Qt::Alignment QwtScaleDraw::labelAlignment | ( | ) | const | 
Definition at line 978 of file qwt_scale_draw.cpp.
| QPointF QwtScaleDraw::labelPosition | ( | double | value | ) | const | 
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().
| value | Value | 
Definition at line 596 of file qwt_scale_draw.cpp.
| QRectF QwtScaleDraw::labelRect | ( | const QFont & | font, | 
| double | value ) const | 
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.
| font | Font used for painting | 
| value | Value | 
Definition at line 887 of file qwt_scale_draw.cpp.
| double QwtScaleDraw::labelRotation | ( | ) | const | 
Definition at line 939 of file qwt_scale_draw.cpp.
| QSizeF QwtScaleDraw::labelSize | ( | const QFont & | font, | 
| double | value ) const | 
Calculate the size that is needed to draw a label
| font | Label font | 
| value | Value | 
Definition at line 912 of file qwt_scale_draw.cpp.
| 
 | protected | 
Calculate the transformation that is needed to paint a label depending on its alignment and rotation.
| pos | Position where to paint the label | 
| size | Size of the label | 
Definition at line 817 of file qwt_scale_draw.cpp.
| double QwtScaleDraw::length | ( | ) | const | 
Definition at line 749 of file qwt_scale_draw.cpp.
| int QwtScaleDraw::maxLabelHeight | ( | const QFont & | font | ) | const | 
| font | Font | 
Definition at line 1010 of file qwt_scale_draw.cpp.
| int QwtScaleDraw::maxLabelWidth | ( | const QFont & | font | ) | const | 
| font | Font | 
Definition at line 987 of file qwt_scale_draw.cpp.
| int QwtScaleDraw::minLabelDist | ( | const QFont & | font | ) | const | 
Determine the minimum distance between two labels, that is necessary that the texts don't overlap.
| font | Font | 
Definition at line 436 of file qwt_scale_draw.cpp.
| int QwtScaleDraw::minLength | ( | const QFont & | font | ) | const | 
Calculate the minimum length that is needed to draw the scale
| font | Font used for painting the labels | 
Definition at line 560 of file qwt_scale_draw.cpp.
| void QwtScaleDraw::move | ( | const QPointF & | pos | ) | 
Move the position of the scale.
The meaning of the parameter pos depends on the alignment:
| pos | Origin of the scale | 
Definition at line 707 of file qwt_scale_draw.cpp.
| 
 | inline | 
Move the position of the scale
| x | X coordinate | 
| y | Y coordinate | 
Definition at line 118 of file qwt_scale_draw.h.
| Qt::Orientation QwtScaleDraw::orientation | ( | ) | const | 
Return the orientation
TopScale, BottomScale are horizontal (Qt::Horizontal) scales, LeftScale, RightScale are vertical (Qt::Vertical) scales.
Definition at line 337 of file qwt_scale_draw.cpp.
| QPointF QwtScaleDraw::pos | ( | ) | const | 
Definition at line 717 of file qwt_scale_draw.cpp.
| void QwtScaleDraw::setAlignment | ( | Alignment | align | ) | 
Set the alignment of the scale
| align | Alignment of the scale | 
The default alignment is QwtScaleDraw::BottomScale
Definition at line 322 of file qwt_scale_draw.cpp.
| void QwtScaleDraw::setLabelAlignment | ( | Qt::Alignment | 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.
| alignment | Or'd Qt::AlignmentFlags see <qnamespace.h> | 
Definition at line 969 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.
| rotation | Angle in degrees. When changing the label rotation, the label flags often needs to be adjusted too. | 
Definition at line 930 of file qwt_scale_draw.cpp.
| void QwtScaleDraw::setLength | ( | double | length | ) | 
Set the length of the backbone.
The length doesn't include the space needed for overlapping labels.
| length | Length of the backbone | 
Definition at line 732 of file qwt_scale_draw.cpp.