QwtPolarSpectrogram Class Reference

An item, which displays a spectrogram. More...

#include <qwt_polar_spectrogram.h>

Inheritance diagram for QwtPolarSpectrogram:
Inheritance graph
[legend]

List of all members.

Public Member Functions

 QwtPolarSpectrogram ()
virtual ~QwtPolarSpectrogram ()
void setData (const QwtRasterData &data)
const QwtRasterData & data () const
void setColorMap (const QwtColorMap &)
const QwtColorMap & colorMap () const
virtual int rtti () const
virtual void draw (QPainter *painter, const QwtScaleMap &azimuthMap, const QwtScaleMap &radialMap, const QwtDoublePoint &pole, double radius, const QwtDoubleRect &canvasRect) const
virtual QwtDoubleInterval boundingInterval (int scaleId) const

Protected Member Functions

virtual QImage renderImage (const QwtScaleMap &azimuthMap, const QwtScaleMap &radialMap, const QwtDoublePoint &pole, const QRect &rect) const

Detailed Description

An item, which displays a spectrogram.

A spectrogram displays threedimenional data, where the 3rd dimension ( the intensity ) is displayed using colors. The colors are calculated from the values using a color map.

See also:
QwtRasterData, QwtColorMap

Constructor & Destructor Documentation

QwtPolarSpectrogram::QwtPolarSpectrogram (  )  [explicit]

Constructor.

QwtPolarSpectrogram::~QwtPolarSpectrogram (  )  [virtual]

Destructor.


Member Function Documentation

QwtDoubleInterval QwtPolarSpectrogram::boundingInterval ( int  scaleId  )  const [virtual]

Interval, that is necessary to display the item This interval can be useful for operations like clipping or autoscaling

Parameters:
scaleId Scale index
Returns:
bounding interval ( == position )
See also:
position()

Reimplemented from QwtPolarItem.

const QwtColorMap & QwtPolarSpectrogram::colorMap (  )  const
Returns:
Color Map used for mapping the intensity values to colors
See also:
setColorMap()
const QwtRasterData & QwtPolarSpectrogram::data (  )  const
Returns:
Spectrogram data
See also:
setData()
void QwtPolarSpectrogram::draw ( QPainter *  painter,
const QwtScaleMap &  azimuthMap,
const QwtScaleMap &  radialMap,
const QwtDoublePoint &  pole,
double  radius,
const QwtDoubleRect &  canvasRect 
) const [virtual]

Draw the spectrogram

Parameters:
painter Painter
azimuthMap Maps azimuth values to values related to 0.0, M_2PI
radialMap Maps radius values into painter coordinates.
pole Position of the pole in painter coordinates
radius Radius of the complete plot area in painter coordinates
canvasRect Contents rect of the canvas in painter coordinates

Implements QwtPolarItem.

QImage QwtPolarSpectrogram::renderImage ( const QwtScaleMap &  azimuthMap,
const QwtScaleMap &  radialMap,
const QwtDoublePoint &  pole,
const QRect &  rect 
) const [protected, virtual]

Render an image from the data and color map.

The area is translated into a rect of the paint device. For each pixel of this rect the intensity is mapped into a color.

Parameters:
azimuthMap Maps azimuth values to values related to 0.0, M_2PI
radialMap Maps radius values into painter coordinates.
pole Position of the pole in painter coordinates
rect Target rectangle of the image in painter coordinates
Returns:
A QImage::Format_Indexed8 or QImage::Format_ARGB32 depending on the color map.
See also:
QwtRasterData::intensity(), QwtColorMap::rgb(), QwtColorMap::colorIndex()
int QwtPolarSpectrogram::rtti (  )  const [virtual]
Returns:
QwtPolarItem::Rtti_PolarSpectrogram

Reimplemented from QwtPolarItem.

void QwtPolarSpectrogram::setColorMap ( const QwtColorMap &  colorMap  ) 

Change the color map

Often it is useful to display the mapping between intensities and colors as an additional plot axis, showing a color bar.

Parameters:
colorMap Color Map
See also:
colorMap(), QwtScaleWidget::setColorBarEnabled(), QwtScaleWidget::setColorMap()
void QwtPolarSpectrogram::setData ( const QwtRasterData &  data  ) 

Set the data to be displayed

Parameters:
data Spectrogram Data
See also:
data()
Warning:
QwtRasterData::initRaster() is called each time before the image is rendered, but without any useful parameters. Also QwtRasterData::rasterHint() is not used.

Generated on 24 Sep 2011 for Qwt Polar User's Guide by  doxygen 1.6.1