GSP
Quick Navigator

Search Site

Unix VPS
A - Starter
B - Basic
C - Preferred
D - Commercial
MPS - Dedicated
Previous VPSs
* Sign Up! *

Support
Contact Us
Online Help
Handbooks
Domain Status
Man Pages

FAQ
Virtual Servers
Pricing
Billing
Technical

Network
Facilities
Connectivity
Topology Map

Miscellaneous
Server Agreement
Year 2038
Credits
 

USA Flag

 

 

Man Pages
QwtPlotItem(3) Qwt User's Guide QwtPlotItem(3)

QwtPlotItem -

#include <qwt_plot_item.h>
Inherits QwtLegendItemManager.
Inherited by QwtPlotCurve, QwtPlotGrid, QwtPlotMarker, QwtPlotRasterItem, QwtPlotScaleItem, and QwtPlotSvgItem.


enum ItemAttribute { Legend = 1, AutoScale = 2 }
 
enum RenderHint { RenderAntialiased = 1 }
 
enum RttiValues { Rtti_PlotItem = 0, Rtti_PlotGrid, Rtti_PlotScale, Rtti_PlotMarker, Rtti_PlotCurve, Rtti_PlotHistogram, Rtti_PlotSpectrogram, Rtti_PlotSVG, Rtti_PlotUserItem = 1000 }
 


QwtPlotItem (const QwtText &title=QwtText())
 
virtual ~QwtPlotItem ()
 
void attach (QwtPlot *plot)
 
virtual QwtDoubleRect boundingRect () const
 
void detach ()
 
virtual void draw (QPainter *painter, const QwtScaleMap &xMap, const QwtScaleMap &yMap, const QRect &canvasRect) const =0
 
void hide ()
 
QwtDoubleRect invTransform (const QwtScaleMap &, const QwtScaleMap &, const QRect &) const
 
bool isVisible () const
 
virtual void itemChanged ()
 
virtual QWidget * legendItem () const
 
QRect paintRect (const QwtScaleMap &, const QwtScaleMap &) const
 
QwtPlot * plot () const
 
virtual int rtti () const
 
QwtDoubleRect scaleRect (const QwtScaleMap &, const QwtScaleMap &) const
 
void setAxis (int xAxis, int yAxis)
 
void setItemAttribute (ItemAttribute, bool on=true)
 
void setRenderHint (RenderHint, bool on=true)
 
void setTitle (const QString &title)
 
void setTitle (const QwtText &title)
 
virtual void setVisible (bool)
 
void setXAxis (int axis)
 
void setYAxis (int axis)
 
void setZ (double z)
 
void show ()
 
bool testItemAttribute (ItemAttribute) const
 
bool testRenderHint (RenderHint) const
 
const QwtText & title () const
 
QRect transform (const QwtScaleMap &, const QwtScaleMap &, const QwtDoubleRect &) const
 
virtual void updateLegend (QwtLegend *) const
 
virtual void updateScaleDiv (const QwtScaleDiv &, const QwtScaleDiv &)
 
int xAxis () const
 
int yAxis () const
 
double z () const
 

Base class for items on the plot canvas.
A plot item is 'something', that can be painted on the plot canvas, or only affects the scales of the plot widget. They can be categorized as:
Representator
 

A 'Representator' is an item that represents some sort of data on the plot canvas. The different representator classes are organized according to the characteristics of the data:
QwtPlotMarker Represents a point or a horizontal/vertical coordinate
QwtPlotCurve Represents a series of points
QwtPlotSpectrogram ( QwtPlotRasterItem ) Represents raster data
...
Decorators
 

A 'Decorator' is an item, that displays additional information, that is not related to any data:
QwtPlotGrid
QwtPlotScaleItem
QwtPlotSvgItem
...
Depending on the QwtPlotItem::ItemAttribute flags, an item is included into autoscaling or has an entry on the legnd.
Before misusing the existing item classes it might be better to implement a new type of plot item ( don't implement a watermark as spectrogram ). Deriving a new type of QwtPlotItem primarily means to implement the YourPlotItem::draw() method.
See also:
The cpuplot example shows the implementation of additional plot items.

Plot Item Attributes
Legend
 

The item is represented on the legend.
AutoScale
 

The boundingRect() of the item is included in the autoscaling calculation.
See also:
setItemAttribute(), testItemAttribute()

Runtime type information. RttiValues is used to cast plot items, without having to enable runtime type information of the compiler.

Constructor
Parameters:
title Title of the item

Attach the item to a plot. This method will attach a QwtPlotItem to the QwtPlot argument. It will first detach the QwtPlotItem from any plot from a previous call to attach (if necessary). If a NULL argument is passed, it will detach from any QwtPlot it was attached to.
Parameters:
plot Plot widget
See also:
QwtPlotItem::detach()

Returns:
An invalid bounding rect: QwtDoubleRect(1.0, 1.0, -2.0, -2.0)
Reimplemented in QwtPlotCurve, QwtPlotMarker, QwtPlotSpectrogram, and QwtPlotSvgItem.

This method detaches a QwtPlotItem from any QwtPlot it has been associated with. detach() is equivalent to calling attach( NULL )
See also:
attach( QwtPlot* plot )

Draw the item. 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
Implemented in QwtPlotCurve, QwtPlotMarker, QwtPlotScaleItem, QwtPlotSpectrogram, QwtPlotRasterItem, QwtPlotGrid, and QwtPlotSvgItem.

Transform a rectangle from paint to scale coordinates
Parameters:
xMap X map
 
yMap Y map
 
rect Rectangle in paint coordinates
Returns:
Rectangle in scale coordinates
See also:
transform()

Returns:
true if visible
See also:
setVisible(), show(), hide()

Update the legend and call QwtPlot::autoRefresh for the parent plot.
See also:
updateLegend()

Allocate the widget that represents the item on the legend. The default implementation is made for QwtPlotCurve and returns a QwtLegendItem(), but an item could be represented by any type of widget, by overloading legendItem() and updateLegend().
Returns:
QwtLegendItem()
See also:
updateLegend() QwtLegend()
Implements QwtLegendItemManager.

Calculate the bounding paint rect of 2 maps. Parameters:
xMap X map
 
yMap X map
Returns:
Bounding rect of the scale maps

Return rtti for the specific class represented. QwtPlotItem is simply a virtual interface class, and base classes will implement this method with specific rtti values so a user can differentiate them.
The rtti value is useful for environments, where the runtime type information is disabled and it is not possible to do a dynamic_cast<...>.
Returns:
rtti value
See also:
RttiValues
Reimplemented in QwtPlotCurve, QwtPlotSpectrogram, QwtPlotMarker, QwtPlotScaleItem, QwtPlotSvgItem, and QwtPlotGrid.

Calculate the bounding scale rect of 2 maps. Parameters:
xMap X map
 
yMap X map
Returns:
Bounding rect of the scale maps

Set X and Y axis
The item will painted according to the coordinates its Axes.
Parameters:
xAxis X Axis
 
yAxis Y Axis
See also:
setXAxis(), setYAxis(), xAxis(), yAxis()

Toggle an item attribute
Parameters:
attribute Attribute type
 
on true/false
See also:
testItemAttribute(), ItemAttribute

Toggle an render hint
Parameters:
hint Render hint
 
on true/false
See also:
testRenderHint(), RenderHint

Set a new title
Parameters:
title Title
See also:
title()

Set a new title
Parameters:
title Title
See also:
title()

Show/Hide the item
Parameters:
on Show if true, otherwise hide
See also:
isVisible(), show(), hide()

Set the X axis
The item will painted according to the coordinates its Axes.
Parameters:
axis X Axis
See also:
setAxis(), setYAxis(), xAxis()

Set the Y axis
The item will painted according to the coordinates its Axes.
Parameters:
axis Y Axis
See also:
setAxis(), setXAxis(), yAxis()

Set the z value. Plot items are painted in increasing z-order.
Parameters:
z Z-value
See also:
z(), QwtPlotDict::itemList()

Test an item attribute
Parameters:
attribute Attribute type
Returns:
true/false
See also:
setItemAttribute(), ItemAttribute

Test a render hint
Parameters:
hint Render hint
Returns:
true/false
See also:
setRenderHint(), RenderHint

Returns:
Title of the item
See also:
setTitle()

Transform a rectangle
Parameters:
xMap X map
 
yMap Y map
 
rect Rectangle in scale coordinates
Returns:
Rectangle in paint coordinates
See also:
invTransform()

Update the widget that represents the item on the legend. updateLegend() is called from itemChanged() to adopt the widget representing the item on the legend to its new configuration.
The default implementation is made for QwtPlotCurve and updates a QwtLegendItem(), but an item could be represented by any type of widget, by overloading legendItem() and updateLegend().
Parameters:
legend Legend
See also:
legendItem(), itemChanged(), QwtLegend()
Implements QwtLegendItemManager.
Reimplemented in QwtPlotCurve.

Update the item to changes of the axes scale division. Update the item, when the axes of plot have changed. The default implementation does nothing, but items that depend on the scale division (like QwtPlotGrid()) have to reimplement updateScaleDiv()
Parameters:
xScaleDiv Scale division of the x-axis
 
yScaleDiv Scale division of the y-axis
See also:
QwtPlot::updateAxes()
Reimplemented in QwtPlotScaleItem, and QwtPlotGrid.

Plot items are painted in increasing z-order.
Returns:
setZ(), QwtPlotDict::itemList()

Generated automatically by Doxygen for Qwt User's Guide from the source code.
Tue Nov 20 2012 Version 5.2.3

Search for    or go to Top of page |  Section 3 |  Main Index

Powered by GSP Visit the GSP FreeBSD Man Page Interface.
Output converted with ManDoc.