QwtRoundScaleDraw Class Reference

A class for drawing round scales. More...

#include <qwt_round_scale_draw.h>

Inheritance diagram for QwtRoundScaleDraw:
Inheritance graph
[legend]

List of all members.

Public Member Functions

 QwtRoundScaleDraw ()
 QwtRoundScaleDraw (const QwtRoundScaleDraw &)
virtual ~QwtRoundScaleDraw ()
QwtRoundScaleDrawoperator= (const QwtRoundScaleDraw &other)
void setRadius (int radius)
int radius () const
void moveCenter (int x, int y)
void moveCenter (const QPoint &)
QPoint center () const
void setAngleRange (double angle1, double angle2)
virtual int extent (const QPen &, const QFont &) const

Protected Member Functions

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 round scales.

QwtRoundScaleDraw can be used to draw round scales. The circle segment can be adjusted by QwtRoundScaleDraw::setAngleRange(). The geometry of the scale can be specified with QwtRoundScaleDraw::moveCenter() and QwtRoundScaleDraw::setRadius().

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.


Constructor & Destructor Documentation

QwtRoundScaleDraw::QwtRoundScaleDraw (  ) 

Constructor.

The range of the scale is initialized to [0, 100], The center is set to (50, 50) with a radius of 50. The angle range is set to [-135, 135].

QwtRoundScaleDraw::QwtRoundScaleDraw ( const QwtRoundScaleDraw other  ) 

Copy constructor.

QwtRoundScaleDraw::~QwtRoundScaleDraw (  )  [virtual]

Destructor.


Member Function Documentation

QPoint QwtRoundScaleDraw::center (  )  const

Get the center of the scale.

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

Draws the baseline of the scale

Parameters:
painter Painter
See also:
drawTick(), drawLabel()

Implements QwtAbstractScaleDraw.

void QwtRoundScaleDraw::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.

void QwtRoundScaleDraw::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.

int QwtRoundScaleDraw::extent ( const QPen &  pen,
const QFont &  font 
) const [virtual]

Calculate the extent of the scale

The extent is the distcance between the baseline to the outermost pixel of the scale draw. radius() + extent() is an upper limit for the radius of the bounding circle.

Parameters:
pen Pen that is used for painting backbone and ticks
font Font used for painting the labels
See also:
setMinimumExtent(), minimumExtent()
Warning:
The implemented algo is not too smart and calculates only an upper limit, that might be a few pixels too large

Implements QwtAbstractScaleDraw.

void QwtRoundScaleDraw::moveCenter ( const QPoint &  center  ) 

Move the center of the scale draw, leaving the radius unchanged

Parameters:
center New center
See also:
setRadius()
void QwtRoundScaleDraw::moveCenter ( int  x,
int  y 
) [inline]

Move the center of the scale draw, leaving the radius unchanged.

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

Assignment operator.

int QwtRoundScaleDraw::radius (  )  const

Get the radius

Radius is the radius of the backbone without ticks and labels.

See also:
setRadius(), extent()
void QwtRoundScaleDraw::setAngleRange ( double  angle1,
double  angle2 
)

Adjust the baseline circle segment for round scales.

The baseline will be drawn from min(angle1,angle2) to max(angle1, angle2). The default setting is [ -135, 135 ]. An angle of 0 degrees corresponds to the 12 o'clock position, and positive angles count in a clockwise direction.

Parameters:
angle1 
angle2 boundaries of the angle interval in degrees.
Warning:
  • The angle range is limited to [-360, 360] degrees. Angles exceeding this range will be clipped.
  • For angles more than 359 degrees above or below min(angle1, angle2), scale marks will not be drawn.
  • If you need a counterclockwise scale, use QwtScaleDiv::setRange
void QwtRoundScaleDraw::setRadius ( int  radius  ) 

Change of radius the scale

Radius is the radius of the backbone without ticks and labels.

Parameters:
radius New Radius
See also:
moveCenter()
Generated on Sun Apr 11 11:56:19 2010 for Qwt User's Guide by  doxygen 1.6.3