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
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