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QwtPlotSpectrogram

QwtPlotSpectrogram

Section: C Library Functions (3) Updated: 22 Mar 2009
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NAME

QwtPlotSpectrogram - A plot item, which displays a spectrogram.

 

SYNOPSIS


#include <qwt_plot_spectrogram.h>

Inherits QwtPlotRasterItem.

 

Public Types


enum DisplayMode { ImageMode = 1, ContourMode = 2 }
 

Public Member Functions


QwtPlotSpectrogram (const QString &title=QString::null)

virtual ~QwtPlotSpectrogram ()

void setDisplayMode (DisplayMode, bool on=true)

bool testDisplayMode (DisplayMode) const

void setData (const QwtRasterData &data)

const QwtRasterData & data () const

void setColorMap (const QwtColorMap &)

const QwtColorMap & colorMap () const

virtual QwtDoubleRect boundingRect () const

virtual QSize rasterHint (const QwtDoubleRect &) const

void setDefaultContourPen (const QPen &)

QPen defaultContourPen () const

virtual QPen contourPen (double level) const

void setConrecAttribute (QwtRasterData::ConrecAttribute, bool on)

bool testConrecAttribute (QwtRasterData::ConrecAttribute) const

void setContourLevels (const QwtValueList &)

QwtValueList contourLevels () const

virtual int rtti () const

virtual void draw (QPainter *p, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRect &rect) const
 

Protected Member Functions


virtual QImage renderImage (const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QwtDoubleRect &rect) const

virtual QSize contourRasterSize (const QwtDoubleRect &, const QRect &) const

virtual QwtRasterData::ContourLines renderContourLines (const QwtDoubleRect &rect, const QSize &raster) const

virtual void drawContourLines (QPainter *p, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QwtRasterData::ContourLines &lines) const
 

Detailed Description

A plot 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.

In ContourMode contour lines are painted for the contour levels.

See also:

QwtRasterData, QwtColorMap

 

Member Enumeration Documentation

 

enum QwtPlotSpectrogram::DisplayMode

The display mode controls how the raster data will be represented.

ImageMode

 The values are mapped to colors using a color map.
ContourMode

 The data is displayed using contour lines

When both modes are enabled the contour lines are painted on top of the spectrogram. The default setting enables ImageMode.

See also:

setDisplayMode(), testDisplayMode()

 

Constructor & Destructor Documentation

 

QwtPlotSpectrogram::QwtPlotSpectrogram (const QString & title = QString::null) [explicit]

Sets the following item attributes:

QwtPlotItem::AutoScale: true
QwtPlotItem::Legend: false

The z value is initialized by 8.0.

Parameters:

title Title

See also:

QwtPlotItem::setItemAttribute(), QwtPlotItem::setZ()

 

QwtPlotSpectrogram::~QwtPlotSpectrogram () [virtual]

Destructor.

 

Member Function Documentation

 

QwtDoubleRect QwtPlotSpectrogram::boundingRect () const [virtual]

Returns:

Bounding rect of the data

See also:

QwtRasterData::boundingRect()

Reimplemented from QwtPlotItem.  

const QwtColorMap & QwtPlotSpectrogram::colorMap () const

Returns:

Color Map used for mapping the intensity values to colors

See also:

setColorMap()

 

QwtValueList QwtPlotSpectrogram::contourLevels () const

Return the levels of the contour lines.

The levels are sorted in increasing order.

See also:

contourLevels(), renderContourLines(), QwtRasterData::contourLines()

 

QPen QwtPlotSpectrogram::contourPen (double level) const [virtual]

Calculate the pen for a contour line.

The color of the pen is the color for level calculated by the color map

Parameters:

level Contour level

Returns:

Pen for the contour line

Note:

contourPen is only used if defaultContourPen().style() == Qt::NoPen

See also:

setDefaultContourPen(), setColorMap(), setContourLevels()

 

QSize QwtPlotSpectrogram::contourRasterSize (const QwtDoubleRect & area, const QRect & rect) const [protected, virtual]

Return the raster to be used by the CONREC contour algorithm.

A larger size will improve the precisision of the CONREC algorithm, but will slow down the time that is needed to calculate the lines.

The default implementation returns rect.size() / 2 bounded to data().rasterHint().

Parameters:

area Rect, where to calculate the contour lines
rect Rect in pixel coordinates, where to paint the contour lines

Returns:

Raster to be used by the CONREC contour algorithm.

Note:

The size will be bounded to rect.size().

See also:

drawContourLines(), QwtRasterData::contourLines()

 

const QwtRasterData & QwtPlotSpectrogram::data () const

Returns:

Spectrogram data

See also:

setData()

 

QPen QwtPlotSpectrogram::defaultContourPen () const

Returns:

Default contour pen

See also:

setDefaultContourPen()

 

void QwtPlotSpectrogram::draw (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRect & canvasRect) const [virtual]

Draw the spectrogram.

Parameters:

painter Painter
xMap Maps x-values into pixel coordinates.
yMap Maps y-values into pixel coordinates.
canvasRect Contents rect of the canvas in painter coordinates

See also:

setDisplayMode(), renderImage(), QwtPlotRasterItem::draw(), drawContourLines()

Reimplemented from QwtPlotRasterItem.  

void QwtPlotSpectrogram::drawContourLines (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QwtRasterData::ContourLines & contourLines) const [protected, virtual]

Paint the contour lines

Parameters:

painter Painter
xMap Maps x-values into pixel coordinates.
yMap Maps y-values into pixel coordinates.
contourLines Contour lines

See also:

renderContourLines(), defaultContourPen(), contourPen()

 

QSize QwtPlotSpectrogram::rasterHint (const QwtDoubleRect & rect) const [virtual]

Returns the recommended raster for a given rect.

F.e the raster hint is used to limit the resolution of the image that is rendered.

Parameters:

rect Rect for the raster hint

Returns:

data().rasterHint(rect)

Reimplemented from QwtPlotRasterItem.  

QwtRasterData::ContourLines QwtPlotSpectrogram::renderContourLines (const QwtDoubleRect & rect, const QSize & raster) const [protected, virtual]

Calculate contour lines

Parameters:

rect Rectangle, where to calculate the contour lines
raster Raster, used by the CONREC algorithm

See also:

contourLevels(), setConrecAttribute(), QwtRasterData::contourLines()

 

QImage QwtPlotSpectrogram::renderImage (const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QwtDoubleRect & area) 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:

xMap X-Scale Map
yMap Y-Scale Map
area Area that should be rendered in scale coordinates.

Returns:

A QImage::Format_Indexed8 or QImage::Format_ARGB32 depending on the color map.

See also:

QwtRasterData::intensity(), QwtColorMap::rgb(), QwtColorMap::colorIndex()

Implements QwtPlotRasterItem.  

int QwtPlotSpectrogram::rtti () const [virtual]

Returns:

QwtPlotItem::Rtti_PlotSpectrogram

Reimplemented from QwtPlotItem.  

void QwtPlotSpectrogram::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 QwtPlotSpectrogram::setConrecAttribute (QwtRasterData::ConrecAttribute attribute, bool on)

Modify an attribute of the CONREC algorithm, used to calculate the contour lines.

Parameters:

attribute CONREC attribute
on On/Off

See also:

testConrecAttribute(), renderContourLines(), QwtRasterData::contourLines()

 

void QwtPlotSpectrogram::setContourLevels (const QwtValueList & levels)

Set the levels of the contour lines

Parameters:

levels Values of the contour levels

See also:

contourLevels(), renderContourLines(), QwtRasterData::contourLines()

Note:

contourLevels returns the same levels but sorted.

 

void QwtPlotSpectrogram::setData (const QwtRasterData & data)

Set the data to be displayed

Parameters:

data Spectrogram Data

See also:

data()

 

void QwtPlotSpectrogram::setDefaultContourPen (const QPen & pen)

Set the default pen for the contour lines.

If the spectrogram has a valid default contour pen a contour line is painted using the default contour pen. Otherwise (pen.style() == Qt::NoPen) the pen is calculated for each contour level using contourPen().

See also:

defaultContourPen(), contourPen()

 

void QwtPlotSpectrogram::setDisplayMode (DisplayMode mode, bool on = true)

The display mode controls how the raster data will be represented.

Parameters:

mode Display mode
on On/Off

The default setting enables ImageMode.

See also:

DisplayMode, displayMode()

 

bool QwtPlotSpectrogram::testConrecAttribute (QwtRasterData::ConrecAttribute attribute) const

Test an attribute of the CONREC algorithm, used to calculate the contour lines.

Parameters:

attribute CONREC attribute

Returns:

true, is enabled

See also:

setConrecAttribute(), renderContourLines(), QwtRasterData::contourLines()

 

bool QwtPlotSpectrogram::testDisplayMode (DisplayMode mode) const

The display mode controls how the raster data will be represented.

Parameters:

mode Display mode

Returns:

true if mode is enabled

 

Author

Generated automatically by Doxygen for Qwt User's Guide from the source code.


 

Index

NAME
SYNOPSIS
Public Types
Public Member Functions
Protected Member Functions
Detailed Description
Member Enumeration Documentation
enum QwtPlotSpectrogram::DisplayMode
Constructor & Destructor Documentation
QwtPlotSpectrogram::QwtPlotSpectrogram (const QString & title = QString::null) [explicit]
QwtPlotSpectrogram::~QwtPlotSpectrogram () [virtual]
Member Function Documentation
QwtDoubleRect QwtPlotSpectrogram::boundingRect () const [virtual]
const QwtColorMap & QwtPlotSpectrogram::colorMap () const
QwtValueList QwtPlotSpectrogram::contourLevels () const
QPen QwtPlotSpectrogram::contourPen (double level) const [virtual]
QSize QwtPlotSpectrogram::contourRasterSize (const QwtDoubleRect & area, const QRect & rect) const [protected, virtual]
const QwtRasterData & QwtPlotSpectrogram::data () const
QPen QwtPlotSpectrogram::defaultContourPen () const
void QwtPlotSpectrogram::draw (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QRect & canvasRect) const [virtual]
void QwtPlotSpectrogram::drawContourLines (QPainter * painter, const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QwtRasterData::ContourLines & contourLines) const [protected, virtual]
QSize QwtPlotSpectrogram::rasterHint (const QwtDoubleRect & rect) const [virtual]
QwtRasterData::ContourLines QwtPlotSpectrogram::renderContourLines (const QwtDoubleRect & rect, const QSize & raster) const [protected, virtual]
QImage QwtPlotSpectrogram::renderImage (const QwtScaleMap & xMap, const QwtScaleMap & yMap, const QwtDoubleRect & area) const [protected, virtual]
int QwtPlotSpectrogram::rtti () const [virtual]
void QwtPlotSpectrogram::setColorMap (const QwtColorMap & colorMap)
void QwtPlotSpectrogram::setConrecAttribute (QwtRasterData::ConrecAttribute attribute, bool on)
void QwtPlotSpectrogram::setContourLevels (const QwtValueList & levels)
void QwtPlotSpectrogram::setData (const QwtRasterData & data)
void QwtPlotSpectrogram::setDefaultContourPen (const QPen & pen)
void QwtPlotSpectrogram::setDisplayMode (DisplayMode mode, bool on = true)
bool QwtPlotSpectrogram::testConrecAttribute (QwtRasterData::ConrecAttribute attribute) const
bool QwtPlotSpectrogram::testDisplayMode (DisplayMode mode) const
Author

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Time: 21:53:53 GMT, April 16, 2011