Qwt User's Guide
QwtScaleMap Class Reference

A scale map. More...

#include <qwt_scale_map.h>

Public Member Functions

 QwtScaleMap ()
 Constructor.
 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.
void setScaleInterval (double s1, double s2)
 Specify the borders of the scale interval.
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.


Constructor & Destructor Documentation

Constructor.

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

Destructor


Member Function Documentation

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()
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()
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()
bool QwtScaleMap::isInverting ( ) const [inline]
Returns:
True, when ( p1() < p2() ) != ( s1() < s2() )
double QwtScaleMap::p1 ( ) const [inline]
Returns:
First border of the paint interval
double QwtScaleMap::p2 ( ) const [inline]
Returns:
Second border of the paint interval
double QwtScaleMap::pDist ( ) const [inline]
Returns:
qwtAbs(p2() - p1())
double QwtScaleMap::s1 ( ) const [inline]
Returns:
First border of the scale interval
double QwtScaleMap::s2 ( ) const [inline]
Returns:
Second border of the scale interval
double QwtScaleMap::sDist ( ) const [inline]
Returns:
qwtAbs(s2() - s1())
void QwtScaleMap::setPaintInterval ( double  p1,
double  p2 
)

Specify the borders of the paint device interval.

Parameters:
p1first border
p2second border
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

Initialize the map with a transformation

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()
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()
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()

List of all members.

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