A class for drawing scales. More...

#include <qwt_scale_draw.h>

Inheritance diagram for QwtScaleDraw:

Collaboration diagram for QwtScaleDraw:

Classes
class	PrivateData
Public Types
enum	Alignment { BottomScale, TopScale, LeftScale, RightScale }
Public Member Functions
	QwtScaleDraw ()
	Constructor.
	QwtScaleDraw (const QwtScaleDraw &)
	Copy constructor.
virtual	~QwtScaleDraw ()
	Destructor.
QwtScaleDraw &	operator= (const QwtScaleDraw &other)
	Assignment operator.
void	getBorderDistHint (const QFont &, int &start, int &end) const
	Determine the minimum border distance.
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 &)
	Move the position of the scale.
void	setLength (int length)
Alignment	alignment () const
void	setAlignment (Alignment)
Qt::Orientation	orientation () const
QPoint	pos () const
int	length () const
void	setLabelAlignment (int)
	Change the label flags.
int	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
QRect	boundingLabelRect (const QFont &, double val) const
Protected Member Functions
QWMatrix	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

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.

Member Enumeration Documentation

enum QwtScaleDraw::Alignment

Alignment of the scale draw

See also:: setAlignment(), alignment()

Enumerator:

BottomScale
TopScale
LeftScale
RightScale

Definition at line 37 of file qwt_scale_draw.h.

{ BottomScale, TopScale, LeftScale, RightScale };

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().

{
    d_data = new QwtScaleDraw::PrivateData;
    setLength(100);
}

QwtScaleDraw::QwtScaleDraw ( const QwtScaleDraw & other )

Copy constructor.

Definition at line 67 of file qwt_scale_draw.cpp.

                                                   :
    QwtAbstractScaleDraw(other)
{
    d_data = new QwtScaleDraw::PrivateData(*other.d_data);
}

QwtScaleDraw::~QwtScaleDraw ( ) [virtual]

Destructor.

Definition at line 74 of file qwt_scale_draw.cpp.

{
    delete d_data;
}

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.

References QwtScaleDraw::PrivateData::alignment.

Referenced by QwtScaleWidget::alignment(), QwtScaleWidget::colorBarRect(), QwtScaleWidget::draw(), QwtPlotScaleItem::draw(), drawBackbone(), drawTick(), labelMatrix(), labelPosition(), QwtScaleWidget::layoutScale(), QwtPlotScaleItem::setAlignment(), QwtSlider::setScaleDraw(), and QwtScaleWidget::setScaleDraw().

{
    return d_data->alignment; 
}

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()

Definition at line 661 of file qwt_scale_draw.cpp.

References QwtText::isEmpty(), labelMatrix(), labelPosition(), labelSize(), pos(), QwtMatrix, QwtText::textSize(), and QwtAbstractScaleDraw::tickLabel().

{
    QwtText lbl = tickLabel(font, value);
    if ( lbl.isEmpty() )
        return QRect(); 

    const QPoint pos = labelPosition(value);
    QSize labelSize = lbl.textSize(font);
    if ( labelSize.height() % 2 )
        labelSize.setHeight(labelSize.height() + 1);

    const QwtMatrix m = labelMatrix( pos, labelSize);
    return m.mapRect(QRect(QPoint(0, 0), labelSize));
}

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(), BottomScale, QwtPainter::drawLine(), LeftScale, QwtScaleDraw::PrivateData::len, QwtScaleDraw::PrivateData::pos, pos(), RightScale, and TopScale.

{
    const int bw2 = painter->pen().width() / 2;

    const QPoint &pos = d_data->pos;
    const int len = d_data->len - 1;

    switch(alignment())
    {
        case LeftScale:
            QwtPainter::drawLine(painter, pos.x() - bw2,
                pos.y(), pos.x() - bw2, pos.y() + len );
            break;
        case RightScale:
            QwtPainter::drawLine(painter, pos.x() + bw2,
                pos.y(), pos.x() + bw2, pos.y() + len);
            break;
        case TopScale:
            QwtPainter::drawLine(painter, pos.x(), pos.y() - bw2,
                pos.x() + len, pos.y() - bw2);
            break;
        case BottomScale:
            QwtPainter::drawLine(painter, pos.x(), pos.y() + bw2,
                pos.x() + len, pos.y() + bw2);
            break;
    }
}

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.

Definition at line 617 of file qwt_scale_draw.cpp.

References QwtText::draw(), QwtText::isEmpty(), labelMatrix(), labelPosition(), labelSize(), QwtMetricsMap::layoutToDevice(), QwtPainter::metricsMap(), pos(), QwtMatrix, QwtPainter::resetMetricsMap(), QwtPainter::setMetricsMap(), QwtText::textSize(), and QwtAbstractScaleDraw::tickLabel().

{
    QwtText lbl = tickLabel(painter->font(), value);
    if ( lbl.isEmpty() )
        return; 

    QPoint pos = labelPosition(value);

    QSize labelSize = lbl.textSize(painter->font());
    if ( labelSize.height() % 2 )
        labelSize.setHeight(labelSize.height() + 1);

    const QwtMetricsMap metricsMap = QwtPainter::metricsMap();
    QwtPainter::resetMetricsMap();

    labelSize = metricsMap.layoutToDevice(labelSize);
    pos = metricsMap.layoutToDevice(pos);
    
    const QwtMatrix m = labelMatrix( pos, labelSize);

    painter->save();
#if QT_VERSION < 0x040000
    painter->setWorldMatrix(m, true);
#else
    painter->setMatrix(m, true);
#endif

    lbl.draw (painter, QRect(QPoint(0, 0), labelSize) );

    QwtPainter::setMetricsMap(metricsMap); // restore metrics map

    painter->restore();
}

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 alignment(), BottomScale, QwtPainter::drawLine(), QwtMetricsMap::isIdentity(), QwtMetricsMap::layoutToDevice(), QwtMetricsMap::layoutToDeviceX(), QwtMetricsMap::layoutToDeviceY(), LeftScale, QwtAbstractScaleDraw::map(), QwtPainter::metricsMap(), orientation(), QwtScaleDraw::PrivateData::pos, pos(), qwtMin, QwtPainter::resetMetricsMap(), RightScale, QwtAbstractScaleDraw::scaleMap(), QwtPainter::setMetricsMap(), and TopScale.

{
    if ( len <= 0 )
        return;

    int pw2 = qwtMin((int)painter->pen().width(), len) / 2;
    
    QwtScaleMap scaleMap = map();
    const QwtMetricsMap metricsMap = QwtPainter::metricsMap();
    QPoint pos = d_data->pos;

    if ( !metricsMap.isIdentity() )
    {
        /*
           The perfect position of the ticks is important.
           To avoid rounding errors we have to use 
           device coordinates.
         */
        QwtPainter::resetMetricsMap();

        pos = metricsMap.layoutToDevice(pos);
    
        if ( orientation() == Qt::Vertical )
        {
            scaleMap.setPaintInterval(
                metricsMap.layoutToDeviceY((int)scaleMap.p1()),
                metricsMap.layoutToDeviceY((int)scaleMap.p2())
            );
            len = metricsMap.layoutToDeviceX(len);
        }
        else
        {
            scaleMap.setPaintInterval(
                metricsMap.layoutToDeviceX((int)scaleMap.p1()),
                metricsMap.layoutToDeviceX((int)scaleMap.p2())
            );
            len = metricsMap.layoutToDeviceY(len);
        }
    }

    const int tval = scaleMap.transform(value);

    switch(alignment())
    {
        case LeftScale:
        {
#if QT_VERSION < 0x040000
            QwtPainter::drawLine(painter, pos.x() + pw2, tval,
                pos.x() - len - 2 * pw2, tval);
#else
            QwtPainter::drawLine(painter, pos.x() - pw2, tval,
                pos.x() - len, tval);
#endif
            break;
        }

        case RightScale:
        {
#if QT_VERSION < 0x040000
            QwtPainter::drawLine(painter, pos.x(), tval,
                pos.x() + len + pw2, tval);
#else
            QwtPainter::drawLine(painter, pos.x() + pw2, tval,
                pos.x() + len, tval);
#endif
            break;
        }
    
        case BottomScale:
        {
#if QT_VERSION < 0x040000
            QwtPainter::drawLine(painter, tval, pos.y(),
                tval, pos.y() + len + 2 * pw2);
#else
            QwtPainter::drawLine(painter, tval, pos.y() + pw2,
                tval, pos.y() + len);
#endif
            break;
        }

        case TopScale:
        {
#if QT_VERSION < 0x040000
            QwtPainter::drawLine(painter, tval, pos.y() + pw2,
                tval, pos.y() - len - 2 * pw2);
#else
            QwtPainter::drawLine(painter, tval, pos.y() - pw2,
                tval, pos.y() - len);
#endif
            break;
        }
    }
    QwtPainter::setMetricsMap(metricsMap); // restore metrics map
}

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::Backbone, QwtAbstractScaleDraw::hasComponent(), QwtAbstractScaleDraw::Labels, QwtAbstractScaleDraw::majTickLength(), maxLabelHeight(), maxLabelWidth(), QwtAbstractScaleDraw::minimumExtent(), orientation(), qwtMax, QwtAbstractScaleDraw::spacing(), and QwtAbstractScaleDraw::Ticks.

Referenced by QwtScaleWidget::dimForLength(), QwtScaleWidget::layoutScale(), QwtThermo::minimumSizeHint(), and QwtSlider::minimumSizeHint().

{
    int d = 0;

    if ( hasComponent(QwtAbstractScaleDraw::Labels) )
    {
        if ( orientation() == Qt::Vertical )
            d = maxLabelWidth(font);
        else
            d = maxLabelHeight(font);

        if ( d > 0 )
            d += spacing();
    }

    if ( hasComponent(QwtAbstractScaleDraw::Ticks) )
    {
        d += majTickLength();
    }

    if ( hasComponent(QwtAbstractScaleDraw::Backbone) )
    {
        const int pw = qwtMax( 1, pen.width() );  // penwidth can be zero
        d += pw;
    }

    d = qwtMax(d, minimumExtent());
    return d;
}

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::Labels, QwtScaleDiv::MajorTick, QwtAbstractScaleDraw::map(), orientation(), qwtAbs, QwtAbstractScaleDraw::scaleDiv(), and QwtScaleDiv::ticks().

Referenced by QwtScaleWidget::getBorderDistHint(), QwtSlider::layoutSlider(), QwtThermo::layoutThermo(), QwtSlider::minimumSizeHint(), and minLength().

{
    start = 0;
    end = 0;
    
    if ( !hasComponent(QwtAbstractScaleDraw::Labels) )
        return;

    const QwtValueList &ticks = scaleDiv().ticks(QwtScaleDiv::MajorTick);
    if ( ticks.count() == 0 ) 
        return;

    QRect lr = labelRect(font, ticks[0]);

    // find the distance between tick and border
    int off = qwtAbs(map().transform(ticks[0]) - qRound(map().p1()));

    if ( orientation() == Qt::Vertical )
        end = lr.bottom() + 1 - off;
    else
        start = -lr.left() - off;

    const int lastTick = ticks.count() - 1;
    lr = labelRect(font, ticks[lastTick]);

    // find the distance between tick and border
    off = qwtAbs(map().transform(ticks[lastTick]) - qRound(map().p2()));

    if ( orientation() == Qt::Vertical )
        start = -lr.top() - off;
    else
        end = lr.right() + 1 - off;

    // if the distance between tick and border is larger
    // than half of the label width/height, we set to 0

    if ( start < 0 )
        start = 0;
    if ( end < 0 )
        end = 0;
}

int QwtScaleDraw::labelAlignment ( ) const

Returns:: the label flags

See also:: setLabelAlignment(), labelRotation()

Definition at line 871 of file qwt_scale_draw.cpp.

Referenced by labelMatrix().

{
    return d_data->labelAlignment;
}

QwtMatrix 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 685 of file qwt_scale_draw.cpp.

References alignment(), BottomScale, labelAlignment(), labelRotation(), LeftScale, QwtMatrix, RightScale, and TopScale.

Referenced by boundingLabelRect(), drawLabel(), and labelRect().

{   
    QwtMatrix m;
    m.translate(pos.x(), pos.y());
    m.rotate(labelRotation());
    
    int flags = labelAlignment();
    if ( flags == 0 )
    {
        switch(alignment())
        {
            case RightScale:
            {
                if ( flags == 0 )
                    flags = Qt::AlignRight | Qt::AlignVCenter;
                break;
            }
            case LeftScale:
            {
                if ( flags == 0 )
                    flags = Qt::AlignLeft | Qt::AlignVCenter;
                break;
            }
            case BottomScale:
            {
                if ( flags == 0 )
                    flags = Qt::AlignHCenter | Qt::AlignBottom;
                break;
            }
            case TopScale:
            {
                if ( flags == 0 )
                    flags = Qt::AlignHCenter | Qt::AlignTop;
                break;
            }
        }
    }

    const int w = size.width();
    const int h = size.height();

    int x, y;
    
    if ( flags & Qt::AlignLeft )
        x = -w;
    else if ( flags & Qt::AlignRight )
        x = -(w % 2); 
    else // Qt::AlignHCenter
        x = -(w / 2);
        
    if ( flags & Qt::AlignTop )
        y =  -h ;
    else if ( flags & Qt::AlignBottom )
        y = -(h % 2); 
    else // Qt::AlignVCenter
        y = -(h/2);
        
    m.translate(x, y);
    
    return m;
}

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(), BottomScale, QuadProgPP::dist(), QwtAbstractScaleDraw::hasComponent(), LeftScale, QwtAbstractScaleDraw::majTickLength(), QwtAbstractScaleDraw::map(), QwtScaleDraw::PrivateData::pos, RightScale, QwtAbstractScaleDraw::spacing(), QwtAbstractScaleDraw::Ticks, TopScale, and QwtScaleMap::transform().

Referenced by boundingLabelRect(), drawLabel(), and labelRect().

{
    const int tval = map().transform(value);
    int dist = spacing() + 1;
    if ( hasComponent(QwtAbstractScaleDraw::Ticks) )
        dist += majTickLength();

    int px = 0;
    int py = 0;

    switch(alignment())
    {
        case RightScale:
        {
            px = d_data->pos.x() + dist;
            py = tval;
            break;
        }
        case LeftScale:
        {
            px = d_data->pos.x() - dist;
            py = tval;
            break;
        }
        case BottomScale:
        {
            px = tval;
            py = d_data->pos.y() + dist;
            break;
        }
        case TopScale:
        {
            px = tval;
            py = d_data->pos.y() - dist;
            break;
        }
    }

    return QPoint(px, py);
}

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 756 of file qwt_scale_draw.cpp.

References QwtText::isEmpty(), labelMatrix(), labelPosition(), labelSize(), pos(), QwtMatrix, QwtText::textSize(), QwtAbstractScaleDraw::tickLabel(), and QwtMetricsMap::translate().

Referenced by getBorderDistHint(), labelSize(), and minLabelDist().

{   
    QwtText lbl = tickLabel(font, value);
    if ( lbl.isEmpty() )
        return QRect(0, 0, 0, 0);

    const QPoint pos = labelPosition(value);

    QSize labelSize = lbl.textSize(font);
    if ( labelSize.height() % 2 )
    {
        labelSize.setHeight(labelSize.height() + 1);
    }

    const QwtMatrix m = labelMatrix(pos, labelSize);

#if 0
    QRect br = QwtMetricsMap::translate(m, QRect(QPoint(0, 0), labelSize));
#else
    QwtPolygon pol(4);
    pol.setPoint(0, 0, 0); 
    pol.setPoint(1, 0, labelSize.height() - 1 );
    pol.setPoint(2, labelSize.width() - 1, 0);
    pol.setPoint(3, labelSize.width() - 1, labelSize.height() - 1 );

    pol = QwtMetricsMap::translate(m, pol);
    QRect br = pol.boundingRect();
#endif

#if QT_VERSION < 0x040000
    br.moveBy(-pos.x(), -pos.y());
#else
    br.translate(-pos.x(), -pos.y());
#endif

    return br;
}

double QwtScaleDraw::labelRotation ( ) const

Returns:: the label rotation

See also:: setLabelRotation(), labelAlignment()

Definition at line 827 of file qwt_scale_draw.cpp.

References QwtScaleDraw::PrivateData::labelRotation.

Referenced by labelMatrix(), and minLabelDist().

{
    return d_data->labelRotation;
}

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 800 of file qwt_scale_draw.cpp.

References labelRect().

Referenced by boundingLabelRect(), drawLabel(), labelRect(), maxLabelHeight(), and maxLabelWidth().

{
    return labelRect(font, value).size();
}

int QwtScaleDraw::length ( ) const

Returns:: the length of the backbone

See also:: setLength(), pos()

Definition at line 604 of file qwt_scale_draw.cpp.

References QwtScaleDraw::PrivateData::len.

Referenced by QwtPlot::printScale(), and setLength().

{
    return d_data->len;
}

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

Parameters:

font Font

Returns:: the maximum height of a label

Definition at line 906 of file qwt_scale_draw.cpp.

References QwtScaleDiv::contains(), labelSize(), QwtScaleDiv::MajorTick, QwtAbstractScaleDraw::scaleDiv(), and QwtScaleDiv::ticks().

Referenced by extent().

{
    int maxHeight = 0;
    
    const QwtValueList &ticks = scaleDiv().ticks(QwtScaleDiv::MajorTick);
    for (uint i = 0; i < (uint)ticks.count(); i++)
    {
        const double v = ticks[i];
        if ( scaleDiv().contains(v) )
        {
            const int h = labelSize(font, ticks[i]).height();
            if ( h > maxHeight )
                maxHeight = h; 
        }       
    }   
    
    return maxHeight;
}

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

Parameters:

font Font

Returns:: the maximum width of a label

Definition at line 883 of file qwt_scale_draw.cpp.

References QwtScaleDiv::contains(), labelSize(), QwtScaleDiv::MajorTick, QwtAbstractScaleDraw::scaleDiv(), and QwtScaleDiv::ticks().

Referenced by extent().

{
    int maxWidth = 0;

    const QwtValueList &ticks = scaleDiv().ticks(QwtScaleDiv::MajorTick);
    for (uint i = 0; i < (uint)ticks.count(); i++)
    {
        const double v = ticks[i];
        if ( scaleDiv().contains(v) )
        {
            const int w = labelSize(font, ticks[i]).width();
            if ( w > maxWidth )
                maxWidth = w;
        }
    }

    return maxWidth;
}

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 QuadProgPP::dist(), QwtAbstractScaleDraw::hasComponent(), int(), labelRect(), labelRotation(), QwtAbstractScaleDraw::Labels, M_PI, QwtScaleDiv::MajorTick, orientation(), QwtAbstractScaleDraw::scaleDiv(), and QwtScaleDiv::ticks().

Referenced by minLength().

{
    if ( !hasComponent(QwtAbstractScaleDraw::Labels) )
        return 0;

    const QwtValueList &ticks = scaleDiv().ticks(QwtScaleDiv::MajorTick);
    if (ticks.count() == 0)
        return 0;

    const QFontMetrics fm(font);

    const bool vertical = (orientation() == Qt::Vertical);

    QRect bRect1;
    QRect bRect2 = labelRect(font, ticks[0]);
    if ( vertical )
    {
        bRect2.setRect(-bRect2.bottom(), 0, bRect2.height(), bRect2.width());
    }
    int maxDist = 0;

    for (uint i = 1; i < (uint)ticks.count(); i++ )
    {
        bRect1 = bRect2;
        bRect2 = labelRect(font, ticks[i]);
        if ( vertical )
        {
            bRect2.setRect(-bRect2.bottom(), 0,
                bRect2.height(), bRect2.width());
        }

        int dist = fm.leading(); // space between the labels
        if ( bRect1.right() > 0 )
            dist += bRect1.right();
        if ( bRect2.left() < 0 )
            dist += -bRect2.left();

        if ( dist > maxDist )
            maxDist = dist;
    }

    double angle = labelRotation() / 180.0 * M_PI;
    if ( vertical )
        angle += M_PI / 2;

    if ( sin(angle) == 0.0 )
        return maxDist;

    const int fmHeight = fm.ascent() - 2; 

    // The distance we need until there is
    // the height of the label font. This height is needed
    // for the neighbour labal.

    int labelDist = (int)(fmHeight / sin(angle) * cos(angle));
    if ( labelDist < 0 )
        labelDist = -labelDist;

    // The cast above floored labelDist. We want to ceil.
    labelDist++; 

    // For text orientations close to the scale orientation 

    if ( labelDist > maxDist )
        labelDist = maxDist;

    // For text orientations close to the opposite of the 
    // scale orientation

    if ( labelDist < fmHeight )
        labelDist = fmHeight;

    return labelDist;
}

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(), QwtAbstractScaleDraw::Labels, QwtScaleDiv::MajorTick, QwtScaleDiv::MediumTick, minLabelDist(), QwtScaleDiv::MinorTick, qwtMax, QwtAbstractScaleDraw::scaleDiv(), QwtAbstractScaleDraw::Ticks, and QwtScaleDiv::ticks().

Referenced by QwtThermo::minimumSizeHint(), QwtSlider::minimumSizeHint(), and QwtScaleWidget::minimumSizeHint().

{
    int startDist, endDist;
    getBorderDistHint(font, startDist, endDist);

    const QwtScaleDiv &sd = scaleDiv();

    const uint minorCount =
        sd.ticks(QwtScaleDiv::MinorTick).count() +
        sd.ticks(QwtScaleDiv::MediumTick).count();
    const uint majorCount =
        sd.ticks(QwtScaleDiv::MajorTick).count();

    int lengthForLabels = 0;
    if ( hasComponent(QwtAbstractScaleDraw::Labels) )
    {
        if ( majorCount >= 2 )
            lengthForLabels = minLabelDist(font) * (majorCount - 1);
    }

    int lengthForTicks = 0;
    if ( hasComponent(QwtAbstractScaleDraw::Ticks) )
    {
        const int pw = qwtMax( 1, pen.width() );  // penwidth can be zero
        lengthForTicks = 2 * (majorCount + minorCount) * pw;
    }

    return startDist + endDist + qwtMax(lengthForLabels, lengthForTicks);
}

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

Move the position of the scale

See also:: move(const QPoint &)

Definition at line 108 of file qwt_scale_draw.h.

Referenced by QwtPlotScaleItem::draw(), QwtScaleWidget::layoutScale(), QwtSlider::layoutSlider(), QwtThermo::layoutThermo(), and QwtPlot::printScale().

{
    move(QPoint(x, y));
}

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.

References pos(), and QwtScaleDraw::PrivateData::pos.

{
    d_data->pos = pos;
    updateMap();
}

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

Assignment operator.

Definition at line 80 of file qwt_scale_draw.cpp.

{
    *(QwtAbstractScaleDraw*)this = (const QwtAbstractScaleDraw &)other;
    *d_data = *other.d_data;
    return *this;
}

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.

References QwtScaleDraw::PrivateData::alignment, BottomScale, LeftScale, RightScale, and TopScale.

Referenced by QwtScaleWidget::colorBarRect(), QwtScaleWidget::draw(), QwtPlotScaleItem::draw(), QwtScaleWidget::drawColorBar(), drawTick(), extent(), getBorderDistHint(), QwtScaleWidget::layoutScale(), QwtScaleWidget::minimumSizeHint(), minLabelDist(), QwtPlot::printScale(), QwtScaleWidget::setAlignment(), and QwtPlotScaleItem::updateScaleDiv().

{
    switch(d_data->alignment)
    {
        case TopScale:
        case BottomScale:
            return Qt::Horizontal;
        case LeftScale:
        case RightScale:
        default:
            return Qt::Vertical;
    }
}

QPoint QwtScaleDraw::pos ( ) const

Returns:: Origin of the scale

See also:: move(), length()

Definition at line 576 of file qwt_scale_draw.cpp.

References QwtScaleDraw::PrivateData::pos.

Referenced by boundingLabelRect(), drawBackbone(), drawLabel(), drawTick(), labelRect(), move(), and QwtPlot::printScale().

{
    return d_data->pos;
}

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.

References QwtScaleDraw::PrivateData::alignment.

Referenced by QwtThermo::layoutThermo(), QwtPlotScaleItem::QwtPlotScaleItem(), QwtScaleWidget::setAlignment(), QwtPlotScaleItem::setAlignment(), QwtSlider::setScaleDraw(), QwtScaleWidget::setScaleDraw(), and QwtSlider::setScalePosition().

{
    d_data->alignment = align;
}

void QwtScaleDraw::setLabelAlignment ( int 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 858 of file qwt_scale_draw.cpp.

{
    d_data->labelAlignment = alignment;
}

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 818 of file qwt_scale_draw.cpp.

References QwtScaleDraw::PrivateData::labelRotation.

Referenced by QwtScaleWidget::setLabelRotation().

{
    d_data->labelRotation = rotation;
}

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.

References QwtScaleDraw::PrivateData::len, and length().

Referenced by QwtPlotScaleItem::draw(), QwtScaleWidget::layoutScale(), QwtSlider::layoutSlider(), QwtThermo::layoutThermo(), QwtPlot::printScale(), and QwtScaleDraw().

{
    if ( length >= 0 && length < 10 )
        length = 10;
    if ( length < 0 && length > -10 )
        length = -10;
    
    d_data->len = length;
    updateMap();
}

The documentation for this class was generated from the following files:

QwtScaleDraw Class Reference

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Public Member Functions

Protected Member Functions

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