Qwt User's Guide  6.2.0
QwtScaleMap Class Reference

A scale map. More...

#include <qwt_scale_map.h>

Public Member Functions

 QwtScaleMap ()
 Constructor. More...
 
 QwtScaleMap (const QwtScaleMap &)
 Copy constructor.
 
 ~QwtScaleMap ()
 
QwtScaleMapoperator= (const QwtScaleMap &)
 Assignment operator.
 
void setTransformation (QwtTransform *)
 
const QwtTransformtransformation () const
 Get the transformation.
 
void setPaintInterval (double p1, double p2)
 Specify the borders of the paint device interval. More...
 
void setScaleInterval (double s1, double s2)
 Specify the borders of the scale interval. More...
 
double transform (double s) const
 
double invTransform (double p) const
 
double p1 () const
 
double p2 () const
 
double s1 () const
 
double s2 () const
 
double pDist () const
 
double sDist () const
 
bool isInverting () const
 

Static Public Member Functions

static QRectF transform (const QwtScaleMap &, const QwtScaleMap &, const QRectF &)
 
static QRectF invTransform (const QwtScaleMap &, const QwtScaleMap &, const QRectF &)
 
static QPointF transform (const QwtScaleMap &, const QwtScaleMap &, const QPointF &)
 
static QPointF invTransform (const QwtScaleMap &, const QwtScaleMap &, const QPointF &)
 

Detailed Description

A scale map.

QwtScaleMap offers transformations from the coordinate system of a scale into the linear coordinate system of a paint device and vice versa.

Definition at line 26 of file qwt_scale_map.h.

Constructor & Destructor Documentation

◆ QwtScaleMap()

QwtScaleMap::QwtScaleMap ( )

Constructor.

The scale and paint device intervals are both set to [0,1].

Definition at line 21 of file qwt_scale_map.cpp.

◆ ~QwtScaleMap()

QwtScaleMap::~QwtScaleMap ( )

Destructor

Definition at line 49 of file qwt_scale_map.cpp.

Member Function Documentation

◆ invTransform() [1/3]

QPointF QwtScaleMap::invTransform ( const QwtScaleMap xMap,
const QwtScaleMap yMap,
const QPointF &  pos 
)
static

Transform a rectangle from paint to scale coordinates

Parameters
xMapX map
yMapY map
posPosition in paint coordinates
Returns
Position in scale coordinates
See also
transform()

Definition at line 187 of file qwt_scale_map.cpp.

◆ invTransform() [2/3]

QRectF QwtScaleMap::invTransform ( const QwtScaleMap xMap,
const QwtScaleMap yMap,
const QRectF &  rect 
)
static

Transform a rectangle from paint to scale coordinates

Parameters
xMapX map
yMapY map
rectRectangle in paint coordinates
Returns
Rectangle in scale coordinates
See also
transform()

Definition at line 224 of file qwt_scale_map.cpp.

◆ invTransform() [3/3]

double QwtScaleMap::invTransform ( double  p) const
inline

Transform an paint device value into a value in the interval of the scale.

Parameters
pValue relative to the coordinates of the paint device
Returns
Transformed value
See also
transform()

Definition at line 154 of file qwt_scale_map.h.

◆ isInverting()

bool QwtScaleMap::isInverting ( ) const
inline
Returns
True, when ( p1() < p2() ) != ( s1() < s2() )

Definition at line 164 of file qwt_scale_map.h.

◆ p1()

double QwtScaleMap::p1 ( ) const
inline
Returns
First border of the paint interval

Definition at line 99 of file qwt_scale_map.h.

◆ p2()

double QwtScaleMap::p2 ( ) const
inline
Returns
Second border of the paint interval

Definition at line 107 of file qwt_scale_map.h.

◆ pDist()

double QwtScaleMap::pDist ( ) const
inline
Returns
qwtAbs(p2() - p1())

Definition at line 115 of file qwt_scale_map.h.

◆ s1()

double QwtScaleMap::s1 ( ) const
inline
Returns
First border of the scale interval

Definition at line 83 of file qwt_scale_map.h.

◆ s2()

double QwtScaleMap::s2 ( ) const
inline
Returns
Second border of the scale interval

Definition at line 91 of file qwt_scale_map.h.

◆ sDist()

double QwtScaleMap::sDist ( ) const
inline
Returns
qwtAbs(s2() - s1())

Definition at line 123 of file qwt_scale_map.h.

◆ setPaintInterval()

void QwtScaleMap::setPaintInterval ( double  p1,
double  p2 
)

Specify the borders of the paint device interval.

Parameters
p1first border
p2second border

Definition at line 119 of file qwt_scale_map.cpp.

◆ setScaleInterval()

void QwtScaleMap::setScaleInterval ( double  s1,
double  s2 
)

Specify the borders of the scale interval.

Parameters
s1first border
s2second border
Warning
scales might be aligned to transformation depending boundaries

Definition at line 100 of file qwt_scale_map.cpp.

◆ setTransformation()

void QwtScaleMap::setTransformation ( QwtTransform transform)

Initialize the map with a transformation

Definition at line 76 of file qwt_scale_map.cpp.

◆ transform() [1/3]

QPointF QwtScaleMap::transform ( const QwtScaleMap xMap,
const QwtScaleMap yMap,
const QPointF &  pos 
)
static

Transform a point from scale to paint coordinates

Parameters
xMapX map
yMapY map
posPosition in scale coordinates
Returns
Position in paint coordinates
See also
invTransform()

Definition at line 206 of file qwt_scale_map.cpp.

◆ transform() [2/3]

QRectF QwtScaleMap::transform ( const QwtScaleMap xMap,
const QwtScaleMap yMap,
const QRectF &  rect 
)
static

Transform a rectangle from scale to paint coordinates

Parameters
xMapX map
yMapY map
rectRectangle in scale coordinates
Returns
Rectangle in paint coordinates
See also
invTransform()

Definition at line 153 of file qwt_scale_map.cpp.

◆ transform() [3/3]

double QwtScaleMap::transform ( double  s) const
inline

Transform a point related to the scale interval into an point related to the interval of the paint device

Parameters
sValue relative to the coordinates of the scale
Returns
Transformed value
See also
invTransform()

Definition at line 137 of file qwt_scale_map.h.